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Mendez Colmenares A, Thomas ML, Anderson C, Arciniegas DB, Calhoun V, Choi IY, Kramer AF, Li K, Lee J, Lee P, Burzynska AZ. Testing the structural disconnection hypothesis: Myelin content correlates with memory in healthy aging. Neurobiol Aging 2024; 141:21-33. [PMID: 38810596 PMCID: PMC11290458 DOI: 10.1016/j.neurobiolaging.2024.05.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 05/07/2024] [Accepted: 05/21/2024] [Indexed: 05/31/2024]
Abstract
INTRODUCTION The "structural disconnection" hypothesis of cognitive aging suggests that deterioration of white matter (WM), especially myelin, results in cognitive decline, yet in vivo evidence is inconclusive. METHODS We examined age differences in WM microstructure using Myelin Water Imaging and Diffusion Tensor Imaging in 141 healthy participants (age 20-79). We used the Virginia Cognitive Aging Project and the NIH Toolbox® to generate composites for memory, processing speed, and executive function. RESULTS Voxel-wise analyses showed that lower myelin water fraction (MWF), predominantly in prefrontal WM, genu of the corpus callosum, and posterior limb of the internal capsule was associated with reduced memory performance after controlling for age, sex, and education. In structural equation modeling, MWF in the prefrontal white matter and genu of the corpus callosum significantly mediated the effect of age on memory, whereas fractional anisotropy (FA) did not. DISCUSSION Our findings support the disconnection hypothesis, showing that myelin decline contributes to age-related memory loss and opens avenues for interventions targeting myelin health.
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Affiliation(s)
- Andrea Mendez Colmenares
- The BRAiN lab, Department of Human Development and Family Studies/Molecular, Cellular and Integrative Neurosciences, Colorado State University, Behavioral Sciences Building, 303, 410 W Pitkin St, Fort Collins, CO 80523, USA
| | - Michael L Thomas
- Department of Psychology, Colorado State University, Behavioral Sciences Building, 303, 410 W Pitkin, St, Fort Collins, CO 80523, USA
| | - Charles Anderson
- Department of Computer Science, Colorado State University, 456 University Ave #444, Fort Collins, CO 80521, USA
| | - David B Arciniegas
- Marcus Institute for Brain Health, University of Colorado Anschutz Medical Campus, 12348 E Montview Blvd, Aurora, CO 80045, USA
| | - Vince Calhoun
- Tri-institutional Center for Translational Research in Neuroimaging and Data Science (TReNDS), Georgia State, Georgia Tech, Emory, 55 Park Pl NE, Atlanta, GA 30303, USA
| | - In-Young Choi
- Department of Neurology, Department of Radiology, Hoglund Biomedical Imaging Center, University of Kansas Medical Center, 3805 Eaton St, Kansas City, KS 66103, USA
| | - Arthur F Kramer
- Beckman Institute for Advanced Science and Technology at the University of Illinois, 405 N Mathews Ave, Urbana, IL 61801, USA; Center for Cognitive & Brain Health, Northeastern University, Address: 360 Huntington Ave, Boston, MA 02115, USA
| | - Kaigang Li
- Department of Health and Exercise Science, Colorado State University, 951 W Plum St, Fort Collins, CO 80521, USA
| | - Jongho Lee
- Department of Electrical and Computer Engineering, Seoul National University, 232 Gongneung-ro, Nowon-gu, Seoul 01811, South Korea
| | - Phil Lee
- Department of Radiology, Hoglund Biomedical Imaging Center, University of Kansas Medical Center, 3805 Eaton St, Kansas City, KS 66103, USA
| | - Agnieszka Z Burzynska
- The BRAiN lab, Department of Human Development and Family Studies/Molecular, Cellular and Integrative Neurosciences, Colorado State University, Behavioral Sciences Building, 303, 410 W Pitkin St, Fort Collins, CO 80523, USA.
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Faulkner ME, Gong Z, Guo A, Laporte JP, Bae J, Bouhrara M. Harnessing myelin water fraction as an imaging biomarker of human cerebral aging, neurodegenerative diseases, and risk factors influencing myelination: A review. J Neurochem 2024. [PMID: 38973579 DOI: 10.1111/jnc.16170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 06/12/2024] [Accepted: 06/19/2024] [Indexed: 07/09/2024]
Abstract
Myelin water fraction (MWF) imaging has emerged as a promising magnetic resonance imaging (MRI) biomarker for investigating brain function and composition. This comprehensive review synthesizes the current state of knowledge on MWF as a biomarker of human cerebral aging, neurodegenerative diseases, and risk factors influencing myelination. The databases used include Web of Science, Scopus, Science Direct, and PubMed. We begin with a brief discussion of the theoretical foundations of MWF imaging, including its basis in MR physics and the mathematical modeling underlying its calculation, with an overview of the most adopted MRI methods of MWF imaging. Next, we delve into the clinical and research applications that have been explored to date, highlighting its advantages and limitations. Finally, we explore the potential of MWF to serve as a predictive biomarker for neurological disorders and identify future research directions for optimizing MWF imaging protocols and interpreting MWF in various contexts. By harnessing the power of MWF imaging, we may gain new insights into brain health and disease across the human lifespan, ultimately informing novel diagnostic and therapeutic strategies.
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Affiliation(s)
- Mary E Faulkner
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Zhaoyuan Gong
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Alex Guo
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - John P Laporte
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Jonghyun Bae
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Mustapha Bouhrara
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
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Parimoo S, Grady C, Olsen R. Age-related Differences in Response Inhibition Are Mediated by Frontoparietal White Matter but Not Functional Activity. J Cogn Neurosci 2024; 36:1184-1205. [PMID: 38579242 DOI: 10.1162/jocn_a_02159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2024]
Abstract
Healthy older adults often exhibit lower performance but increased functional recruitment of the frontoparietal control network during cognitive control tasks. According to the cortical disconnection hypothesis, age-related changes in the microstructural integrity of white matter may disrupt inter-regional neuronal communication, which in turn can impair behavioral performance. Here, we use fMRI and diffusion-weighted imaging to determine whether age-related differences in white matter microstructure contribute to frontoparietal over-recruitment and behavioral performance during a response inhibition (go/no-go) task in an adult life span sample (n = 145). Older and female participants were slower (go RTs) than younger and male participants, respectively. However, participants across all ages were equally accurate on the no-go trials, suggesting some participants may slow down on go trials to achieve high accuracy on no-go trials. Across the life span, functional recruitment of the frontoparietal network within the left and right hemispheres did not vary as a function of age, nor was it related to white matter fractional anisotropy (FA). In fact, only frontal FA and go RTs jointly mediated the association between age and no-go accuracy. Our results therefore suggest that frontal white matter cortical "disconnection" is an underlying driver of age-related differences in cognitive control, and white matter FA may not fully explain functional task-related activation in the frontoparietal network during the go/no-go task. Our findings add to the literature by demonstrating that white matter may be more important for certain cognitive processes in aging than task-related functional activation.
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Affiliation(s)
- Shireen Parimoo
- University of Toronto
- Rotman Research Institute, Baycrest, Toronto, Canada
| | - Cheryl Grady
- University of Toronto
- Rotman Research Institute, Baycrest, Toronto, Canada
| | - Rosanna Olsen
- University of Toronto
- Rotman Research Institute, Baycrest, Toronto, Canada
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Kraft JN, Matijevic S, Hoagey DA, Kennedy KM, Rodrigue KM. Differential Effects of Aging on Regional Corpus Callosum Microstructure and the Modifying Influence of Pulse Pressure. eNeuro 2024; 11:ENEURO.0449-23.2024. [PMID: 38719452 PMCID: PMC11106647 DOI: 10.1523/eneuro.0449-23.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 03/29/2024] [Accepted: 04/02/2024] [Indexed: 05/18/2024] Open
Abstract
The corpus callosum is composed of several subregions, distinct in cellular and functional organization. This organization scheme may render these subregions differentially vulnerable to the aging process. Callosal integrity may be further compromised by cardiovascular risk factors, which negatively influence white matter health. Here, we test for heterochronicity of aging, hypothesizing an anteroposterior gradient of vulnerability to aging that may be altered by the effects of cardiovascular health. In 174 healthy adults across the adult lifespan (mean age = 53.56 ± 18.90; range, 20-94 years old, 58.62% women), pulse pressure (calculated as participant's systolic minus diastolic blood pressure) was assessed to determine cardiovascular risk. A deterministic tractography approach via diffusion-weighted imaging was utilized to extract fractional anisotropy (FA), radial diffusivity (RD), and axial diffusivity (AD) from each of five callosal subregions, serving as estimates of microstructural health. General linear models tested the effects of age, hypertension, and pulse pressure on these cross-sectional metrics. We observed no significant effect of hypertensive diagnosis on callosal microstructure. We found a significant main effect of age and an age-pulse pressure interaction whereby older age and elevated pulse pressure were associated with poorer FA, AD, and RD. Age effects revealed nonlinear components and occurred along an anteroposterior gradient of severity in the callosum. This gradient disappeared when pulse pressure was considered. These results indicate that age-related deterioration across the callosum is regionally variable and that pulse pressure, a proxy of arterial stiffness, exacerbates this aging pattern in a large lifespan cohort.
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Affiliation(s)
- Jessica N Kraft
- Center for Vital Longevity, Department of Psychology, School of Behavioral and Brain Sciences, The University of Texas at Dallas, Dallas, Texas 75235
| | - Stephanie Matijevic
- Center for Vital Longevity, Department of Psychology, School of Behavioral and Brain Sciences, The University of Texas at Dallas, Dallas, Texas 75235
- Department of Psychology, University of Arizona, Tucson, Arizona 85721
| | - David A Hoagey
- Center for Vital Longevity, Department of Psychology, School of Behavioral and Brain Sciences, The University of Texas at Dallas, Dallas, Texas 75235
| | - Kristen M Kennedy
- Center for Vital Longevity, Department of Psychology, School of Behavioral and Brain Sciences, The University of Texas at Dallas, Dallas, Texas 75235
| | - Karen M Rodrigue
- Center for Vital Longevity, Department of Psychology, School of Behavioral and Brain Sciences, The University of Texas at Dallas, Dallas, Texas 75235
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Rivera AD, Normanton JR, Butt AM, Azim K. The Genomic Intersection of Oligodendrocyte Dynamics in Schizophrenia and Aging Unravels Novel Pathological Mechanisms and Therapeutic Potentials. Int J Mol Sci 2024; 25:4452. [PMID: 38674040 PMCID: PMC11050044 DOI: 10.3390/ijms25084452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 03/28/2024] [Accepted: 03/30/2024] [Indexed: 04/28/2024] Open
Abstract
Schizophrenia is a significant worldwide health concern, affecting over 20 million individuals and contributing to a potential reduction in life expectancy by up to 14.5 years. Despite its profound impact, the precise pathological mechanisms underlying schizophrenia continue to remain enigmatic, with previous research yielding diverse and occasionally conflicting findings. Nonetheless, one consistently observed phenomenon in brain imaging studies of schizophrenia patients is the disruption of white matter, the bundles of myelinated axons that provide connectivity and rapid signalling between brain regions. Myelin is produced by specialised glial cells known as oligodendrocytes, which have been shown to be disrupted in post-mortem analyses of schizophrenia patients. Oligodendrocytes are generated throughout life by a major population of oligodendrocyte progenitor cells (OPC), which are essential for white matter health and plasticity. Notably, a decline in a specific subpopulation of OPC has been identified as a principal factor in oligodendrocyte disruption and white matter loss in the aging brain, suggesting this may also be a factor in schizophrenia. In this review, we analysed genomic databases to pinpoint intersections between aging and schizophrenia and identify shared mechanisms of white matter disruption and cognitive dysfunction.
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Affiliation(s)
- Andrea D. Rivera
- Department of Neuroscience, Institute of Human Anatomy, University of Padova, Via A. Gabelli 65, 35127 Padua, Italy;
| | - John R. Normanton
- GliaGenesis Limited, Orchard Lea, Horns Lane, Oxfordshire, Witney OX29 8NH, UK; (J.R.N.); (K.A.)
| | - Arthur M. Butt
- GliaGenesis Limited, Orchard Lea, Horns Lane, Oxfordshire, Witney OX29 8NH, UK; (J.R.N.); (K.A.)
- School of Pharmacy and Biomedical Science, University of Portsmouth, Hampshire PO1 2UP, UK
| | - Kasum Azim
- GliaGenesis Limited, Orchard Lea, Horns Lane, Oxfordshire, Witney OX29 8NH, UK; (J.R.N.); (K.A.)
- Independent Data Lab UG, Frauenmantelanger 31, 80937 Munich, Germany
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Maboudian SA, Willbrand EH, Kelly JP, Jagust WJ, Weiner KS. Defining Overlooked Structures Reveals New Associations between the Cortex and Cognition in Aging and Alzheimer's Disease. J Neurosci 2024; 44:e1714232024. [PMID: 38383497 PMCID: PMC11026365 DOI: 10.1523/jneurosci.1714-23.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Revised: 01/05/2024] [Accepted: 01/27/2024] [Indexed: 02/23/2024] Open
Abstract
Recent work suggests that indentations of the cerebral cortex, or sulci, may be uniquely vulnerable to atrophy in aging and Alzheimer's disease (AD) and that the posteromedial cortex (PMC) is particularly vulnerable to atrophy and pathology accumulation. However, these studies did not consider small, shallow, and variable tertiary sulci that are located in association cortices and are often associated with human-specific aspects of cognition. Here, we manually defined 4,362 PMC sulci in 432 hemispheres in 216 human participants (50.5% female) and found that these smaller putative tertiary sulci showed more age- and AD-related thinning than larger, more consistent sulci, with the strongest effects for two newly uncovered sulci. A model-based approach relating sulcal morphology to cognition identified that a subset of these sulci was most associated with memory and executive function scores in older adults. These findings lend support to the retrogenesis hypothesis linking brain development and aging and provide new neuroanatomical targets for future studies of aging and AD.
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Affiliation(s)
- Samira A Maboudian
- Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, California 94720
- Department of Neuroscience, University of California Berkeley, Berkeley, California 94720
| | - Ethan H Willbrand
- School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin 53726
| | - Joseph P Kelly
- Department of Medical Social Sciences, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
| | - William J Jagust
- Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, California 94720
- Department of Neuroscience, University of California Berkeley, Berkeley, California 94720
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Kevin S Weiner
- Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, California 94720
- Department of Neuroscience, University of California Berkeley, Berkeley, California 94720
- Department of Psychology, University of California Berkeley, Berkeley, California 94720
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7
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Wang Q, Schindler SE, Chen G, Mckay NS, McCullough A, Flores S, Liu J, Sun Z, Wang S, Wang W, Hassenstab J, Cruchaga C, Perrin RJ, Fagan AM, Morris JC, Wang Y, Benzinger TLS. Investigating White Matter Neuroinflammation in Alzheimer Disease Using Diffusion-Based Neuroinflammation Imaging. Neurology 2024; 102:e208013. [PMID: 38315956 PMCID: PMC10890836 DOI: 10.1212/wnl.0000000000208013] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 10/13/2023] [Indexed: 02/07/2024] Open
Abstract
BACKGROUND AND OBJECTIVES Alzheimer disease (AD) is primarily associated with accumulations of amyloid plaques and tau tangles in gray matter, however, it is now acknowledged that neuroinflammation, particularly in white matter (WM), significantly contributes to the development and progression of AD. This study aims to investigate WM neuroinflammation in the continuum of AD and its association with AD pathologies and cognition using diffusion-based neuroinflammation imaging (NII). METHODS This is a cross-sectional, single-center, retrospective evaluation conducted on an observational study of 310 older research participants who were enrolled in the Knight Alzheimer's Disease Research Center cohort. Hindered water ratio (HR), an index of WM neuroinflammation, was quantified by a noninvasive diffusion MRI method, NII. The alterations of NII-HR were investigated at different AD stages, classified based on CSF concentrations of β-amyloid (Aβ) 42/Aβ40 for amyloid and phosphorylated tau181 (p-tau181) for tau. On the voxel and regional levels, the relationship between NII-HR and CSF markers of amyloid, tau, and neuroinflammation were examined, as well as cognition. RESULTS This cross-sectional study included 310 participants (mean age 67.1 [±9.1] years), with 52 percent being female. Subgroups included 120 individuals (38.7%) with CSF measures of soluble triggering receptor expressed on myeloid cells 2, 80 participants (25.8%) with CSF measures of chitinase-3-like protein 1, and 110 individuals (35.5%) with longitudinal cognitive measures. The study found that cognitively normal individuals with positive CSF Aβ42/Aβ40 and p-tau181 had higher HR than healthy controls and those with positive CSF Aβ42/Aβ40 but negative p-tau181. WM tracts with elevated NII-HR in individuals with positive CSF Aβ42/Aβ40 and p-tau181 were primarily located in the posterior brain regions while those with elevated NII-HR in individuals with positive CSF Aβ42/Aβ40 and p-tau181 connected the posterior and anterior brain regions. A significant negative correlation between NII-HR and CSF Aβ42/Aβ40 was found in individuals with positive CSF Aβ42/Aβ40. Baseline NII-HR correlated with baseline cognitive composite score and predicted longitudinal cognitive decline. DISCUSSION Those findings suggest that WM neuroinflammation undergoes alterations before the onset of AD clinical symptoms and that it interacts with amyloidosis. This highlights the potential value of noninvasive monitoring of WM neuroinflammation in AD progression and treatment.
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Affiliation(s)
- Qing Wang
- From the Mallinckrodt Institute of Radiology (Q.W., G.C., N.S.M., A.M., S.F., Y.W., T.L.S.B.), Knight Alzheimer Disease Research Center (Q.W., S.E.S., G.C., N.S.M., A.M., J.H., R.J.P., A.M.F., J.C.M., T.L.S.B.), Department of Neurology (S.E.S., J.H., C.C., A.M.F., J.C.M.), Department of Surgery (J.L.), Department of Biomedical Engineering (Z.S.), Department of Electrical and System Engineering (S.W., W.W., Y.W.), Department of Psychiatry (C.C.), Department of Pathology & Immunology (R.J.P.), Department of Obstetrics & Gynecology (Y.W.), and Department of Neurosurgery (T.L.S.B.), Washington University School of Medicine, St. Louis, MO
| | - Suzanne E Schindler
- From the Mallinckrodt Institute of Radiology (Q.W., G.C., N.S.M., A.M., S.F., Y.W., T.L.S.B.), Knight Alzheimer Disease Research Center (Q.W., S.E.S., G.C., N.S.M., A.M., J.H., R.J.P., A.M.F., J.C.M., T.L.S.B.), Department of Neurology (S.E.S., J.H., C.C., A.M.F., J.C.M.), Department of Surgery (J.L.), Department of Biomedical Engineering (Z.S.), Department of Electrical and System Engineering (S.W., W.W., Y.W.), Department of Psychiatry (C.C.), Department of Pathology & Immunology (R.J.P.), Department of Obstetrics & Gynecology (Y.W.), and Department of Neurosurgery (T.L.S.B.), Washington University School of Medicine, St. Louis, MO
| | - Gengsheng Chen
- From the Mallinckrodt Institute of Radiology (Q.W., G.C., N.S.M., A.M., S.F., Y.W., T.L.S.B.), Knight Alzheimer Disease Research Center (Q.W., S.E.S., G.C., N.S.M., A.M., J.H., R.J.P., A.M.F., J.C.M., T.L.S.B.), Department of Neurology (S.E.S., J.H., C.C., A.M.F., J.C.M.), Department of Surgery (J.L.), Department of Biomedical Engineering (Z.S.), Department of Electrical and System Engineering (S.W., W.W., Y.W.), Department of Psychiatry (C.C.), Department of Pathology & Immunology (R.J.P.), Department of Obstetrics & Gynecology (Y.W.), and Department of Neurosurgery (T.L.S.B.), Washington University School of Medicine, St. Louis, MO
| | - Nicole S Mckay
- From the Mallinckrodt Institute of Radiology (Q.W., G.C., N.S.M., A.M., S.F., Y.W., T.L.S.B.), Knight Alzheimer Disease Research Center (Q.W., S.E.S., G.C., N.S.M., A.M., J.H., R.J.P., A.M.F., J.C.M., T.L.S.B.), Department of Neurology (S.E.S., J.H., C.C., A.M.F., J.C.M.), Department of Surgery (J.L.), Department of Biomedical Engineering (Z.S.), Department of Electrical and System Engineering (S.W., W.W., Y.W.), Department of Psychiatry (C.C.), Department of Pathology & Immunology (R.J.P.), Department of Obstetrics & Gynecology (Y.W.), and Department of Neurosurgery (T.L.S.B.), Washington University School of Medicine, St. Louis, MO
| | - Austin McCullough
- From the Mallinckrodt Institute of Radiology (Q.W., G.C., N.S.M., A.M., S.F., Y.W., T.L.S.B.), Knight Alzheimer Disease Research Center (Q.W., S.E.S., G.C., N.S.M., A.M., J.H., R.J.P., A.M.F., J.C.M., T.L.S.B.), Department of Neurology (S.E.S., J.H., C.C., A.M.F., J.C.M.), Department of Surgery (J.L.), Department of Biomedical Engineering (Z.S.), Department of Electrical and System Engineering (S.W., W.W., Y.W.), Department of Psychiatry (C.C.), Department of Pathology & Immunology (R.J.P.), Department of Obstetrics & Gynecology (Y.W.), and Department of Neurosurgery (T.L.S.B.), Washington University School of Medicine, St. Louis, MO
| | - Shaney Flores
- From the Mallinckrodt Institute of Radiology (Q.W., G.C., N.S.M., A.M., S.F., Y.W., T.L.S.B.), Knight Alzheimer Disease Research Center (Q.W., S.E.S., G.C., N.S.M., A.M., J.H., R.J.P., A.M.F., J.C.M., T.L.S.B.), Department of Neurology (S.E.S., J.H., C.C., A.M.F., J.C.M.), Department of Surgery (J.L.), Department of Biomedical Engineering (Z.S.), Department of Electrical and System Engineering (S.W., W.W., Y.W.), Department of Psychiatry (C.C.), Department of Pathology & Immunology (R.J.P.), Department of Obstetrics & Gynecology (Y.W.), and Department of Neurosurgery (T.L.S.B.), Washington University School of Medicine, St. Louis, MO
| | - Jingxia Liu
- From the Mallinckrodt Institute of Radiology (Q.W., G.C., N.S.M., A.M., S.F., Y.W., T.L.S.B.), Knight Alzheimer Disease Research Center (Q.W., S.E.S., G.C., N.S.M., A.M., J.H., R.J.P., A.M.F., J.C.M., T.L.S.B.), Department of Neurology (S.E.S., J.H., C.C., A.M.F., J.C.M.), Department of Surgery (J.L.), Department of Biomedical Engineering (Z.S.), Department of Electrical and System Engineering (S.W., W.W., Y.W.), Department of Psychiatry (C.C.), Department of Pathology & Immunology (R.J.P.), Department of Obstetrics & Gynecology (Y.W.), and Department of Neurosurgery (T.L.S.B.), Washington University School of Medicine, St. Louis, MO
| | - Zhexian Sun
- From the Mallinckrodt Institute of Radiology (Q.W., G.C., N.S.M., A.M., S.F., Y.W., T.L.S.B.), Knight Alzheimer Disease Research Center (Q.W., S.E.S., G.C., N.S.M., A.M., J.H., R.J.P., A.M.F., J.C.M., T.L.S.B.), Department of Neurology (S.E.S., J.H., C.C., A.M.F., J.C.M.), Department of Surgery (J.L.), Department of Biomedical Engineering (Z.S.), Department of Electrical and System Engineering (S.W., W.W., Y.W.), Department of Psychiatry (C.C.), Department of Pathology & Immunology (R.J.P.), Department of Obstetrics & Gynecology (Y.W.), and Department of Neurosurgery (T.L.S.B.), Washington University School of Medicine, St. Louis, MO
| | - Sicheng Wang
- From the Mallinckrodt Institute of Radiology (Q.W., G.C., N.S.M., A.M., S.F., Y.W., T.L.S.B.), Knight Alzheimer Disease Research Center (Q.W., S.E.S., G.C., N.S.M., A.M., J.H., R.J.P., A.M.F., J.C.M., T.L.S.B.), Department of Neurology (S.E.S., J.H., C.C., A.M.F., J.C.M.), Department of Surgery (J.L.), Department of Biomedical Engineering (Z.S.), Department of Electrical and System Engineering (S.W., W.W., Y.W.), Department of Psychiatry (C.C.), Department of Pathology & Immunology (R.J.P.), Department of Obstetrics & Gynecology (Y.W.), and Department of Neurosurgery (T.L.S.B.), Washington University School of Medicine, St. Louis, MO
| | - Wenshang Wang
- From the Mallinckrodt Institute of Radiology (Q.W., G.C., N.S.M., A.M., S.F., Y.W., T.L.S.B.), Knight Alzheimer Disease Research Center (Q.W., S.E.S., G.C., N.S.M., A.M., J.H., R.J.P., A.M.F., J.C.M., T.L.S.B.), Department of Neurology (S.E.S., J.H., C.C., A.M.F., J.C.M.), Department of Surgery (J.L.), Department of Biomedical Engineering (Z.S.), Department of Electrical and System Engineering (S.W., W.W., Y.W.), Department of Psychiatry (C.C.), Department of Pathology & Immunology (R.J.P.), Department of Obstetrics & Gynecology (Y.W.), and Department of Neurosurgery (T.L.S.B.), Washington University School of Medicine, St. Louis, MO
| | - Jason Hassenstab
- From the Mallinckrodt Institute of Radiology (Q.W., G.C., N.S.M., A.M., S.F., Y.W., T.L.S.B.), Knight Alzheimer Disease Research Center (Q.W., S.E.S., G.C., N.S.M., A.M., J.H., R.J.P., A.M.F., J.C.M., T.L.S.B.), Department of Neurology (S.E.S., J.H., C.C., A.M.F., J.C.M.), Department of Surgery (J.L.), Department of Biomedical Engineering (Z.S.), Department of Electrical and System Engineering (S.W., W.W., Y.W.), Department of Psychiatry (C.C.), Department of Pathology & Immunology (R.J.P.), Department of Obstetrics & Gynecology (Y.W.), and Department of Neurosurgery (T.L.S.B.), Washington University School of Medicine, St. Louis, MO
| | - Carlos Cruchaga
- From the Mallinckrodt Institute of Radiology (Q.W., G.C., N.S.M., A.M., S.F., Y.W., T.L.S.B.), Knight Alzheimer Disease Research Center (Q.W., S.E.S., G.C., N.S.M., A.M., J.H., R.J.P., A.M.F., J.C.M., T.L.S.B.), Department of Neurology (S.E.S., J.H., C.C., A.M.F., J.C.M.), Department of Surgery (J.L.), Department of Biomedical Engineering (Z.S.), Department of Electrical and System Engineering (S.W., W.W., Y.W.), Department of Psychiatry (C.C.), Department of Pathology & Immunology (R.J.P.), Department of Obstetrics & Gynecology (Y.W.), and Department of Neurosurgery (T.L.S.B.), Washington University School of Medicine, St. Louis, MO
| | - Richard J Perrin
- From the Mallinckrodt Institute of Radiology (Q.W., G.C., N.S.M., A.M., S.F., Y.W., T.L.S.B.), Knight Alzheimer Disease Research Center (Q.W., S.E.S., G.C., N.S.M., A.M., J.H., R.J.P., A.M.F., J.C.M., T.L.S.B.), Department of Neurology (S.E.S., J.H., C.C., A.M.F., J.C.M.), Department of Surgery (J.L.), Department of Biomedical Engineering (Z.S.), Department of Electrical and System Engineering (S.W., W.W., Y.W.), Department of Psychiatry (C.C.), Department of Pathology & Immunology (R.J.P.), Department of Obstetrics & Gynecology (Y.W.), and Department of Neurosurgery (T.L.S.B.), Washington University School of Medicine, St. Louis, MO
| | - Anne M Fagan
- From the Mallinckrodt Institute of Radiology (Q.W., G.C., N.S.M., A.M., S.F., Y.W., T.L.S.B.), Knight Alzheimer Disease Research Center (Q.W., S.E.S., G.C., N.S.M., A.M., J.H., R.J.P., A.M.F., J.C.M., T.L.S.B.), Department of Neurology (S.E.S., J.H., C.C., A.M.F., J.C.M.), Department of Surgery (J.L.), Department of Biomedical Engineering (Z.S.), Department of Electrical and System Engineering (S.W., W.W., Y.W.), Department of Psychiatry (C.C.), Department of Pathology & Immunology (R.J.P.), Department of Obstetrics & Gynecology (Y.W.), and Department of Neurosurgery (T.L.S.B.), Washington University School of Medicine, St. Louis, MO
| | - John C Morris
- From the Mallinckrodt Institute of Radiology (Q.W., G.C., N.S.M., A.M., S.F., Y.W., T.L.S.B.), Knight Alzheimer Disease Research Center (Q.W., S.E.S., G.C., N.S.M., A.M., J.H., R.J.P., A.M.F., J.C.M., T.L.S.B.), Department of Neurology (S.E.S., J.H., C.C., A.M.F., J.C.M.), Department of Surgery (J.L.), Department of Biomedical Engineering (Z.S.), Department of Electrical and System Engineering (S.W., W.W., Y.W.), Department of Psychiatry (C.C.), Department of Pathology & Immunology (R.J.P.), Department of Obstetrics & Gynecology (Y.W.), and Department of Neurosurgery (T.L.S.B.), Washington University School of Medicine, St. Louis, MO
| | - Yong Wang
- From the Mallinckrodt Institute of Radiology (Q.W., G.C., N.S.M., A.M., S.F., Y.W., T.L.S.B.), Knight Alzheimer Disease Research Center (Q.W., S.E.S., G.C., N.S.M., A.M., J.H., R.J.P., A.M.F., J.C.M., T.L.S.B.), Department of Neurology (S.E.S., J.H., C.C., A.M.F., J.C.M.), Department of Surgery (J.L.), Department of Biomedical Engineering (Z.S.), Department of Electrical and System Engineering (S.W., W.W., Y.W.), Department of Psychiatry (C.C.), Department of Pathology & Immunology (R.J.P.), Department of Obstetrics & Gynecology (Y.W.), and Department of Neurosurgery (T.L.S.B.), Washington University School of Medicine, St. Louis, MO
| | - Tammie L S Benzinger
- From the Mallinckrodt Institute of Radiology (Q.W., G.C., N.S.M., A.M., S.F., Y.W., T.L.S.B.), Knight Alzheimer Disease Research Center (Q.W., S.E.S., G.C., N.S.M., A.M., J.H., R.J.P., A.M.F., J.C.M., T.L.S.B.), Department of Neurology (S.E.S., J.H., C.C., A.M.F., J.C.M.), Department of Surgery (J.L.), Department of Biomedical Engineering (Z.S.), Department of Electrical and System Engineering (S.W., W.W., Y.W.), Department of Psychiatry (C.C.), Department of Pathology & Immunology (R.J.P.), Department of Obstetrics & Gynecology (Y.W.), and Department of Neurosurgery (T.L.S.B.), Washington University School of Medicine, St. Louis, MO
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8
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Vadinova V, Sihvonen AJ, Wee F, Garden KL, Ziraldo L, Roxbury T, O'Brien K, Copland DA, McMahon KL, Brownsett SLE. The volume and the distribution of premorbid white matter hyperintensities: Impact on post-stroke aphasia. Hum Brain Mapp 2024; 45:e26568. [PMID: 38224539 PMCID: PMC10789210 DOI: 10.1002/hbm.26568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 11/29/2023] [Accepted: 12/04/2023] [Indexed: 01/17/2024] Open
Abstract
White matter hyperintensities (WMH) are a radiological manifestation of progressive white matter integrity loss. The total volume and distribution of WMH within the corpus callosum have been associated with pathological cognitive ageing processes but have not been considered in relation to post-stroke aphasia outcomes. We investigated the contribution of both the total volume of WMH, and the extent of WMH lesion load in the corpus callosum to the recovery of language after first-ever stroke. Behavioural and neuroimaging data from individuals (N = 37) with a left-hemisphere stroke were included at the early subacute stage of recovery. Spoken language comprehension and production abilities were assessed using word and sentence-level tasks. Neuroimaging data was used to derive stroke lesion variables (volume and lesion load to language critical regions) and WMH variables (WMH volume and lesion load to three callosal segments). WMH volume did not predict variance in language measures, when considered together with stroke lesion and demographic variables. However, WMH lesion load in the forceps minor segment of the corpus callosum explained variance in early subacute comprehension abilities (t = -2.59, p = .01) together with corrected stroke lesion volume and socio-demographic variables. Premorbid WMH lesions in the forceps minor were negatively associated with early subacute language comprehension after aphasic stroke. This negative impact of callosal WMH on language is consistent with converging evidence from pathological ageing suggesting that callosal WMH disrupt the neural networks supporting a range of cognitive functions.
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Affiliation(s)
- Veronika Vadinova
- Queensland Aphasia Research CentreUniversity of QueenslandBrisbaneAustralia
- School of Health and Rehabilitation SciencesUniversity of QueenslandBrisbaneAustralia
- Centre of Research Excellence in Aphasia Recovery and RehabilitationLa Trobe UniversityMelbourneAustralia
| | - A. J. Sihvonen
- Queensland Aphasia Research CentreUniversity of QueenslandBrisbaneAustralia
- School of Health and Rehabilitation SciencesUniversity of QueenslandBrisbaneAustralia
- Centre of Research Excellence in Aphasia Recovery and RehabilitationLa Trobe UniversityMelbourneAustralia
- Cognitive Brain Research Unit (CBRU)University of HelsinkiHelsinkiFinland
- Centre of Excellence in Music, Mind, Body and BrainUniversity of HelsinkiHelsinkiFinland
| | - F. Wee
- Queensland Aphasia Research CentreUniversity of QueenslandBrisbaneAustralia
| | - K. L. Garden
- Queensland Aphasia Research CentreUniversity of QueenslandBrisbaneAustralia
- School of Health and Rehabilitation SciencesUniversity of QueenslandBrisbaneAustralia
- Centre of Research Excellence in Aphasia Recovery and RehabilitationLa Trobe UniversityMelbourneAustralia
| | - L. Ziraldo
- Queensland Aphasia Research CentreUniversity of QueenslandBrisbaneAustralia
| | - T. Roxbury
- Queensland Aphasia Research CentreUniversity of QueenslandBrisbaneAustralia
| | - K. O'Brien
- Queensland Aphasia Research CentreUniversity of QueenslandBrisbaneAustralia
| | - D. A. Copland
- Queensland Aphasia Research CentreUniversity of QueenslandBrisbaneAustralia
- School of Health and Rehabilitation SciencesUniversity of QueenslandBrisbaneAustralia
- Centre of Research Excellence in Aphasia Recovery and RehabilitationLa Trobe UniversityMelbourneAustralia
| | - K. L. McMahon
- School of Clinical Sciences, Centre for Biomedical TechnologiesQueensland University of TechnologyBrisbaneAustralia
| | - S. L. E. Brownsett
- Queensland Aphasia Research CentreUniversity of QueenslandBrisbaneAustralia
- School of Health and Rehabilitation SciencesUniversity of QueenslandBrisbaneAustralia
- Centre of Research Excellence in Aphasia Recovery and RehabilitationLa Trobe UniversityMelbourneAustralia
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9
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Archer DB, Schilling K, Shashikumar N, Jasodanand V, Moore EE, Pechman KR, Bilgel M, Beason‐Held LL, An Y, Shafer A, Ferrucci L, Risacher SL, Gifford KA, Landman BA, Jefferson AL, Saykin AJ, Resnick SM, Hohman TJ. Leveraging longitudinal diffusion MRI data to quantify differences in white matter microstructural decline in normal and abnormal aging. ALZHEIMER'S & DEMENTIA (AMSTERDAM, NETHERLANDS) 2023; 15:e12468. [PMID: 37780863 PMCID: PMC10540270 DOI: 10.1002/dad2.12468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 06/27/2023] [Accepted: 07/05/2023] [Indexed: 10/03/2023]
Abstract
Introduction It is unclear how rates of white matter microstructural decline differ between normal aging and abnormal aging. Methods Diffusion MRI data from several well-established longitudinal cohorts of aging (Alzheimer's Disease Neuroimaging Initiative [ADNI], Baltimore Longitudinal Study of Aging [BLSA], Vanderbilt Memory & Aging Project [VMAP]) were free-water corrected and harmonized. This dataset included 1723 participants (age at baseline: 72.8 ± 8.87 years, 49.5% male) and 4605 imaging sessions (follow-up time: 2.97 ± 2.09 years, follow-up range: 1-13 years, mean number of visits: 4.42 ± 1.98). Differences in white matter microstructural decline in normal and abnormal agers was assessed. Results While we found a global decline in white matter in normal/abnormal aging, we found that several white matter tracts (e.g., cingulum bundle) were vulnerable to abnormal aging. Conclusions There is a prevalent role of white matter microstructural decline in aging, and future large-scale studies in this area may further refine our understanding of the underlying neurodegenerative processes. HIGHLIGHTS Longitudinal data were free-water corrected and harmonized.Global effects of white matter decline were seen in normal and abnormal aging.The free-water metric was most vulnerable to abnormal aging.Cingulum free-water was the most vulnerable to abnormal aging.
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Affiliation(s)
- Derek B. Archer
- Vanderbilt Memory and Alzheimer's CenterVanderbilt University School of MedicineNashvilleTennesseeUSA
- Vanderbilt Genetics InstituteVanderbilt University Medical CenterNashvilleTennesseeUSA
| | - Kurt Schilling
- Vanderbilt University Institute of Imaging ScienceVanderbilt University Medical CenterNashvilleTennesseeUSA
- Department of Radiology & Radiological SciencesVanderbilt University Medical CenterNashvilleTennesseeUSA
| | - Niranjana Shashikumar
- Vanderbilt Memory and Alzheimer's CenterVanderbilt University School of MedicineNashvilleTennesseeUSA
| | - Varuna Jasodanand
- Vanderbilt Memory and Alzheimer's CenterVanderbilt University School of MedicineNashvilleTennesseeUSA
| | - Elizabeth E. Moore
- Vanderbilt Memory and Alzheimer's CenterVanderbilt University School of MedicineNashvilleTennesseeUSA
| | - Kimberly R. Pechman
- Vanderbilt Memory and Alzheimer's CenterVanderbilt University School of MedicineNashvilleTennesseeUSA
| | - Murat Bilgel
- Laboratory of Behavioral NeuroscienceNational Institute on AgingNational Institutes of HealthBaltimoreMarylandUSA
| | - Lori L. Beason‐Held
- Laboratory of Behavioral NeuroscienceNational Institute on AgingNational Institutes of HealthBaltimoreMarylandUSA
| | - Yang An
- Laboratory of Behavioral NeuroscienceNational Institute on AgingNational Institutes of HealthBaltimoreMarylandUSA
| | - Andrea Shafer
- Laboratory of Behavioral NeuroscienceNational Institute on AgingNational Institutes of HealthBaltimoreMarylandUSA
| | - Luigi Ferrucci
- Longitudinal Studies Section, Translational Gerontology BranchNational Institute on AgingBaltimoreMDUSA
| | - Shannon L. Risacher
- Indiana University School of MedicineIndianapolisIndianaUSA
- Indiana Alzheimer's Disease Research CenterIndianapolisIndianaUSA
| | - Katherine A. Gifford
- Vanderbilt Memory and Alzheimer's CenterVanderbilt University School of MedicineNashvilleTennesseeUSA
| | - Bennett A. Landman
- Vanderbilt University Institute of Imaging ScienceVanderbilt University Medical CenterNashvilleTennesseeUSA
- Department of Radiology & Radiological SciencesVanderbilt University Medical CenterNashvilleTennesseeUSA
- Department of Biomedical EngineeringVanderbilt UniversityNashvilleTennesseeUSA
- Department of Electrical and Computer EngineeringVanderbilt UniversityNashvilleTennesseeUSA
| | - Angela L. Jefferson
- Vanderbilt Memory and Alzheimer's CenterVanderbilt University School of MedicineNashvilleTennesseeUSA
- Department of MedicineVanderbilt University Medical CenterNashvilleTennesseeUSA
| | - Andrew J. Saykin
- Indiana University School of MedicineIndianapolisIndianaUSA
- Indiana Alzheimer's Disease Research CenterIndianapolisIndianaUSA
| | - Susan M. Resnick
- Laboratory of Behavioral NeuroscienceNational Institute on AgingNational Institutes of HealthBaltimoreMarylandUSA
| | - Timothy J. Hohman
- Vanderbilt Memory and Alzheimer's CenterVanderbilt University School of MedicineNashvilleTennesseeUSA
- Vanderbilt Genetics InstituteVanderbilt University Medical CenterNashvilleTennesseeUSA
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10
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Schilling KG, Chad JA, Chamberland M, Nozais V, Rheault F, Archer D, Li M, Gao Y, Cai L, Del'Acqua F, Newton A, Moyer D, Gore JC, Lebel C, Landman BA. White matter tract microstructure, macrostructure, and associated cortical gray matter morphology across the lifespan. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.25.559330. [PMID: 37808645 PMCID: PMC10557619 DOI: 10.1101/2023.09.25.559330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Characterizing how, when and where the human brain changes across the lifespan is fundamental to our understanding of developmental processes of childhood and adolescence, degenerative processes of aging, and divergence from normal patterns in disease and disorders. We aimed to provide detailed descriptions of white matter pathways across the lifespan by thoroughly characterizing white matter microstructure, white matter macrostructure, and morphology of the cortex associated with white matter pathways. We analyzed 4 large, high-quality, publicly-available datasets comprising 2789 total imaging sessions, and participants ranging from 0 to 100 years old, using advanced tractography and diffusion modeling. We first find that all microstructural, macrostructural, and cortical features of white matter bundles show unique lifespan trajectories, with rates and timing of development and degradation that vary across pathways - describing differences between types of pathways and locations in the brain, and developmental milestones of maturation of each feature. Second, we show cross-sectional relationships between different features that may help elucidate biological changes occurring during different stages of the lifespan. Third, we show unique trajectories of age-associations across features. Finally, we find that age associations during development are strongly related to those during aging. Overall, this study reports normative data for several features of white matter pathways of the human brain that will be useful for studying normal and abnormal white matter development and degeneration.
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Affiliation(s)
- Kurt G Schilling
- Department of Radiology & Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Jordan A Chad
- Rotman Research Institute, Baycrest Academy for Research and Education, Toronto, ON, Canada
- Department of Radiology, University of Calgary, Calgary, AB, Canada
| | - Maxime Chamberland
- Department of Mathematics and Computer Science, Eindhoven University of Technology, Eindhoven, The Netherlands
| | | | - Francois Rheault
- Medical Imaging and Neuroinformatic (MINi) Lab, Department of Computer Science, University of Sherbrooke, Canada
| | - Derek Archer
- Vanderbilt Memory & Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, 37212, USA
- Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Muwei Li
- Department of Radiology & Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Yurui Gao
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
| | - Leon Cai
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
| | - Flavio Del'Acqua
- NatbrainLab, Department of Forensics and Neurodevelopmental Sciences, King's College London, London UK
| | - Allen Newton
- Department of Radiology & Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Daniel Moyer
- Department of Electrical and Computer Engineering, Vanderbilt University, Nashville, TN, USA
- Department of Computer Science, Vanderbilt University, Nashville, TN, USA
| | - John C Gore
- Department of Radiology & Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
| | - Catherine Lebel
- Alberta Children's Hospital Research Institute (ACHRI), Calgary, AB, Canada
- Department of Radiology, University of Calgary, Calgary, AB, Canada
| | - Bennett A Landman
- Department of Radiology & Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Electrical and Computer Engineering, Vanderbilt University, Nashville, TN, USA
- Department of Computer Science, Vanderbilt University, Nashville, TN, USA
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11
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Maboudian SA, Willbrand EH, Jagust WJ, Weiner KS. Defining overlooked structures reveals new associations between cortex and cognition in aging and Alzheimer's disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.29.546558. [PMID: 37425904 PMCID: PMC10327001 DOI: 10.1101/2023.06.29.546558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
Recent work suggests that indentations of the cerebral cortex, or sulci, may be uniquely vulnerable to atrophy in aging and Alzheimer's disease (AD) and that posteromedial cortex (PMC) is particularly vulnerable to atrophy and pathology accumulation. However, these studies did not consider small, shallow, and variable tertiary sulci that are located in association cortices and are often associated with human-specific aspects of cognition. Here, we first manually defined 4,362 PMC sulci in 432 hemispheres in 216 participants. Tertiary sulci showed more age- and AD-related thinning than non-tertiary sulci, with the strongest effects for two newly uncovered tertiary sulci. A model-based approach relating sulcal morphology to cognition identified that a subset of these sulci were most associated with memory and executive function scores in older adults. These findings support the retrogenesis hypothesis linking brain development and aging, and provide new neuroanatomical targets for future studies of aging and AD.
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Affiliation(s)
- Samira A. Maboudian
- Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA, 94720 USA
| | - Ethan H. Willbrand
- Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA, 94720 USA
- Department of Psychology, University of California Berkeley, Berkeley, CA, 94720 USA
| | - William J. Jagust
- Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA, 94720 USA
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Kevin S. Weiner
- Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA, 94720 USA
- Department of Psychology, University of California Berkeley, Berkeley, CA, 94720 USA
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12
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Archer DB, Schilling K, Shashikumar N, Jasodanand V, Moore EE, Pechman KR, Bilgel M, Beason-Held LL, An Y, Shafer A, Ferrucci L, Risacher SL, Gifford KA, Landman BA, Jefferson AL, Saykin AJ, Resnick SM, Hohman TJ. Leveraging longitudinal diffusion MRI data to quantify differences in white matter microstructural decline in normal and abnormal aging. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.17.541182. [PMID: 37292885 PMCID: PMC10245725 DOI: 10.1101/2023.05.17.541182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
INTRODUCTION It is unclear how rates of white matter microstructural decline differ between normal aging and abnormal aging. METHODS Diffusion MRI data from several well-established longitudinal cohorts of aging [Alzheimer's Neuroimaging Initiative (ADNI), Baltimore Longitudinal Study of Aging (BLSA), Vanderbilt Memory & Aging Project (VMAP)] was free-water corrected and harmonized. This dataset included 1,723 participants (age at baseline: 72.8±8.87 years, 49.5% male) and 4,605 imaging sessions (follow-up time: 2.97±2.09 years, follow-up range: 1-13 years, mean number of visits: 4.42±1.98). Differences in white matter microstructural decline in normal and abnormal agers was assessed. RESULTS While we found global decline in white matter in normal/abnormal aging, we found that several white matter tracts (e.g., cingulum bundle) were vulnerable to abnormal aging. CONCLUSIONS There is a prevalent role of white matter microstructural decline in aging, and future large-scale studies in this area may further refine our understanding of the underlying neurodegenerative processes. HIGHLIGHTS Longitudinal data was free-water corrected and harmonizedGlobal effects of white matter decline were seen in normal and abnormal agingThe free-water metric was most vulnerable to abnormal agingCingulum free-water was the most vulnerable to abnormal aging.
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Affiliation(s)
- Derek B. Archer
- Vanderbilt Memory and Alzheimer’s Center, Vanderbilt University School of Medicine, Nashville, TN, USA
- Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Kurt Schilling
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Radiology & Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Niranjana Shashikumar
- Vanderbilt Memory and Alzheimer’s Center, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Varuna Jasodanand
- Vanderbilt Memory and Alzheimer’s Center, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Elizabeth E. Moore
- Vanderbilt Memory and Alzheimer’s Center, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Kimberly R. Pechman
- Vanderbilt Memory and Alzheimer’s Center, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Murat Bilgel
- Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Lori L. Beason-Held
- Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Yang An
- Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Andrea Shafer
- Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | | | - Shannon L. Risacher
- Indiana University School of Medicine, Indianapolis, IN, USA
- Indiana Alzheimer’s Disease Research Center, Indianapolis, IN, USA
| | - Katherine A. Gifford
- Vanderbilt Memory and Alzheimer’s Center, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Bennett A. Landman
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
- Department of Electrical and Computer Engineering, Vanderbilt University, Nashville, TN, USA
- Department of Radiology & Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Angela L. Jefferson
- Vanderbilt Memory and Alzheimer’s Center, Vanderbilt University School of Medicine, Nashville, TN, USA
- Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Andrew J. Saykin
- Indiana University School of Medicine, Indianapolis, IN, USA
- Indiana Alzheimer’s Disease Research Center, Indianapolis, IN, USA
| | - Susan M. Resnick
- Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Timothy J. Hohman
- Vanderbilt Memory and Alzheimer’s Center, Vanderbilt University School of Medicine, Nashville, TN, USA
- Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, USA
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13
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Laporte JP, Faulkner ME, Gong Z, Palchamy E, Akhonda MA, Bouhrara M. Investigation of the association between central arterial stiffness and aggregate g-ratio in cognitively unimpaired adults. Front Neurol 2023; 14:1170457. [PMID: 37181577 PMCID: PMC10167487 DOI: 10.3389/fneur.2023.1170457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 04/03/2023] [Indexed: 05/16/2023] Open
Abstract
Stiffness of the large arteries has been shown to impact cerebral white matter (WM) microstructure in both younger and older adults. However, no study has yet demonstrated an association between arterial stiffness and aggregate g-ratio, a specific magnetic resonance imaging (MRI) measure of axonal myelination that is highly correlated with neuronal signal conduction speed. In a cohort of 38 well-documented cognitively unimpaired adults spanning a wide age range, we investigated the association between central arterial stiffness, measured using pulse wave velocity (PWV), and aggregate g-ratio, measured using our recent advanced quantitative MRI methodology, in several cerebral WM structures. After adjusting for age, sex, smoking status, and systolic blood pressure, our results indicate that higher PWV values, that is, elevated arterial stiffness, were associated with lower aggregate g-ratio values, that is, lower microstructural integrity of WM. Compared to other brain regions, these associations were stronger and highly significant in the splenium of the corpus callosum and the internal capsules, which have been consistently documented as very sensitive to elevated arterial stiffness. Moreover, our detailed analysis indicates that these associations were mainly driven by differences in myelination, measured using myelin volume fraction, rather than axonal density, measured using axonal volume fraction. Our findings suggest that arterial stiffness is associated with myelin degeneration, and encourages further longitudinal studies in larger study cohorts. Controlling arterial stiffness may represent a therapeutic target in maintaining the health of WM tissue in cerebral normative aging.
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Affiliation(s)
| | | | | | | | | | - Mustapha Bouhrara
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
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14
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Mendez Colmenares A, Hefner MB, Calhoun VD, Salerno EA, Fanning J, Gothe NP, McAuley E, Kramer AF, Burzynska AZ. Symmetric data-driven fusion of diffusion tensor MRI: Age differences in white matter. Front Neurol 2023; 14:1094313. [PMID: 37139071 PMCID: PMC10149813 DOI: 10.3389/fneur.2023.1094313] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 03/24/2023] [Indexed: 05/05/2023] Open
Abstract
In the past 20 years, white matter (WM) microstructure has been studied predominantly using diffusion tensor imaging (DTI). Decreases in fractional anisotropy (FA) and increases in mean (MD) and radial diffusivity (RD) have been consistently reported in healthy aging and neurodegenerative diseases. To date, DTI parameters have been studied individually (e.g., only FA) and separately (i.e., without using the joint information across them). This approach gives limited insights into WM pathology, increases the number of multiple comparisons, and yields inconsistent correlations with cognition. To take full advantage of the information in a DTI dataset, we present the first application of symmetric fusion to study healthy aging WM. This data-driven approach allows simultaneous examination of age differences in all four DTI parameters. We used multiset canonical correlation analysis with joint independent component analysis (mCCA + jICA) in cognitively healthy adults (age 20-33, n = 51 and age 60-79, n = 170). Four-way mCCA + jICA yielded one high-stability modality-shared component with co-variant patterns of age differences in RD and AD in the corpus callosum, internal capsule, and prefrontal WM. The mixing coefficients (or loading parameters) showed correlations with processing speed and fluid abilities that were not detected by unimodal analyses. In sum, mCCA + jICA allows data-driven identification of cognitively relevant multimodal components within the WM. The presented method should be further extended to clinical samples and other MR techniques (e.g., myelin water imaging) to test the potential of mCCA+jICA to discriminate between different WM disease etiologies and improve the diagnostic classification of WM diseases.
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Affiliation(s)
- Andrea Mendez Colmenares
- BRAiN Laboratory, Department of Human Development and Family Studies, Colorado State University, Fort Collins, CO, United States
- Molecular, Cellular and Integrative Neurosciences, Colorado State University, Fort Collins, CO, United States
| | - Michelle B. Hefner
- BRAiN Laboratory, Department of Human Development and Family Studies, Colorado State University, Fort Collins, CO, United States
| | - Vince D. Calhoun
- Tri-institutional Center for Translational Research in Neuroimaging and Data Science (TReNDS), Georgia State, Georgia Tech, Emory, Atlanta, GA, United States
| | - Elizabeth A. Salerno
- Division of Public Health Sciences, Department of Surgery, Washington University School of Medicine in St. Louis, St. Louis, MO, United States
| | - Jason Fanning
- Department of Health and Exercise Sciences, Wake Forest University, Winston-Salem, NC, United States
| | - Neha P. Gothe
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Edward McAuley
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, IL, United States
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Arthur F. Kramer
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, United States
- Department of Psychology, Northeastern University, Boston, MA, United States
| | - Agnieszka Z. Burzynska
- BRAiN Laboratory, Department of Human Development and Family Studies, Colorado State University, Fort Collins, CO, United States
- Molecular, Cellular and Integrative Neurosciences, Colorado State University, Fort Collins, CO, United States
- Department of Human Development and Family Studies, Colorado State University, Fort Collins, CO, United States
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15
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Paquola C, Hong SJ. The Potential of Myelin-Sensitive Imaging: Redefining Spatiotemporal Patterns of Myeloarchitecture. Biol Psychiatry 2023; 93:442-454. [PMID: 36481065 DOI: 10.1016/j.biopsych.2022.08.031] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 08/12/2022] [Accepted: 08/30/2022] [Indexed: 02/07/2023]
Abstract
Recent advances in magnetic resonance imaging (MRI) have paved the way for approximation of myelin content in vivo. In this review, our main goal was to determine how to best capitalize on myelin-sensitive imaging. First, we briefly overview the theoretical and empirical basis for the myelin sensitivity of different MRI markers and, in doing so, highlight how multimodal imaging approaches are important for enhancing specificity to myelin. Then, we discuss recent studies that have probed the nonuniform distribution of myelin across cortical layers and along white matter tracts. These approaches, collectively known as myelin profiling, have provided detailed depictions of myeloarchitecture in both the postmortem and living human brain. Notably, MRI-based profiling studies have recently focused on investigating whether it can capture interindividual variability in myelin characteristics as well as trajectories across the lifespan. Finally, another line of recent evidence emphasizes the contribution of region-specific myelination to large-scale organization, demonstrating the impact of myelination on global brain networks. In conclusion, we suggest that combining well-validated MRI markers with profiling techniques holds strong potential to elucidate individual differences in myeloarchitecture, which has important implications for understanding brain function and disease.
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Affiliation(s)
- Casey Paquola
- Institute of Neuroscience and Medicine, Forschungszentrum Jülich, Jülich, Germany.
| | - Seok-Jun Hong
- Center for Neuroscience Imaging Research, Institute for Basic Science, Sungkyunkwan University, Suwon, South Korea; Center for the Developing Brain, Child Mind Institute, New York, New York; Department of Biomedical Engineering, Sungkyunkwan University, Suwon, South Korea
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16
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Sharp FR, DeCarli CS, Jin LW, Zhan X. White matter injury, cholesterol dysmetabolism, and APP/Abeta dysmetabolism interact to produce Alzheimer's disease (AD) neuropathology: A hypothesis and review. Front Aging Neurosci 2023; 15:1096206. [PMID: 36845656 PMCID: PMC9950279 DOI: 10.3389/fnagi.2023.1096206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 01/30/2023] [Indexed: 02/12/2023] Open
Abstract
We postulate that myelin injury contributes to cholesterol release from myelin and cholesterol dysmetabolism which contributes to Abeta dysmetabolism, and combined with genetic and AD risk factors, leads to increased Abeta and amyloid plaques. Increased Abeta damages myelin to form a vicious injury cycle. Thus, white matter injury, cholesterol dysmetabolism and Abeta dysmetabolism interact to produce or worsen AD neuropathology. The amyloid cascade is the leading hypothesis for the cause of Alzheimer's disease (AD). The failure of clinical trials based on this hypothesis has raised other possibilities. Even with a possible new success (Lecanemab), it is not clear whether this is a cause or a result of the disease. With the discovery in 1993 that the apolipoprotein E type 4 allele (APOE4) was the major risk factor for sporadic, late-onset AD (LOAD), there has been increasing interest in cholesterol in AD since APOE is a major cholesterol transporter. Recent studies show that cholesterol metabolism is intricately involved with Abeta (Aβ)/amyloid transport and metabolism, with cholesterol down-regulating the Aβ LRP1 transporter and upregulating the Aβ RAGE receptor, both of which would increase brain Aβ. Moreover, manipulating cholesterol transport and metabolism in rodent AD models can ameliorate pathology and cognitive deficits, or worsen them depending upon the manipulation. Though white matter (WM) injury has been noted in AD brain since Alzheimer's initial observations, recent studies have shown abnormal white matter in every AD brain. Moreover, there is age-related WM injury in normal individuals that occurs earlier and is worse with the APOE4 genotype. Moreover, WM injury precedes formation of plaques and tangles in human Familial Alzheimer's disease (FAD) and precedes plaque formation in rodent AD models. Restoring WM in rodent AD models improves cognition without affecting AD pathology. Thus, we postulate that the amyloid cascade, cholesterol dysmetabolism and white matter injury interact to produce and/or worsen AD pathology. We further postulate that the primary initiating event could be related to any of the three, with age a major factor for WM injury, diet and APOE4 and other genes a factor for cholesterol dysmetabolism, and FAD and other genes for Abeta dysmetabolism.
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Affiliation(s)
| | - Charles S. DeCarli
- Department of Neurology, The MIND Institute, University of California at Davis Medical Center, Sacramento, CA, United States
| | - Lee-Way Jin
- Department of Neurology, The MIND Institute, University of California at Davis Medical Center, Sacramento, CA, United States
| | - Xinhua Zhan
- Department of Neurology, The MIND Institute, University of California at Davis Medical Center, Sacramento, CA, United States
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17
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Murray CJ, Vecchiarelli HA, Tremblay MÈ. Enhancing axonal myelination in seniors: A review exploring the potential impact cannabis has on myelination in the aged brain. Front Aging Neurosci 2023; 15:1119552. [PMID: 37032821 PMCID: PMC10073480 DOI: 10.3389/fnagi.2023.1119552] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 02/22/2023] [Indexed: 04/11/2023] Open
Abstract
Consumption of cannabis is on the rise as public opinion trends toward acceptance and its consequent legalization. Specifically, the senior population is one of the demographics increasing their use of cannabis the fastest, but research aimed at understanding cannabis' impact on the aged brain is still scarce. Aging is characterized by many brain changes that slowly alter cognitive ability. One process that is greatly impacted during aging is axonal myelination. The slow degradation and loss of myelin (i.e., demyelination) in the brain with age has been shown to associate with cognitive decline and, furthermore, is a common characteristic of numerous neurological diseases experienced in aging. It is currently not known what causes this age-dependent degradation, but it is likely due to numerous confounding factors (i.e., heightened inflammation, reduced blood flow, cellular senescence) that impact the many cells responsible for maintaining overall homeostasis and myelin integrity. Importantly, animal studies using non-human primates and rodents have also revealed demyelination with age, providing a reliable model for researchers to try and understand the cellular mechanisms at play. In rodents, cannabis was recently shown to modulate the myelination process. Furthermore, studies looking at the direct modulatory impact cannabis has on microglia, astrocytes and oligodendrocyte lineage cells hint at potential mechanisms to prevent some of the more damaging activities performed by these cells that contribute to demyelination in aging. However, research focusing on how cannabis impacts myelination in the aged brain is lacking. Therefore, this review will explore the evidence thus far accumulated to show how cannabis impacts myelination and will extrapolate what this knowledge may mean for the aged brain.
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Affiliation(s)
- Colin J. Murray
- Neuroscience Graduate Program, University of Victoria, Victoria, BC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- *Correspondence: Colin J. Murray,
| | | | - Marie-Ève Tremblay
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Départment de Médicine Moléculaire, Université Laval, Québec City, QC, Canada
- Axe Neurosciences, Center de Recherche du CHU de Québec, Université Laval, Québec City, QC, Canada
- Neurology and Neurosurgery Department, McGill University, Montréal, QC, Canada
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada
- Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria, Victoria, BC, Canada
- Institute for Aging and Lifelong Health, University of Victoria, Victoria, BC, Canada
- Marie-Ève Tremblay,
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18
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Eikenes L, Visser E, Vangberg T, Håberg AK. Both brain size and biological sex contribute to variation in white matter microstructure in middle-aged healthy adults. Hum Brain Mapp 2022; 44:691-709. [PMID: 36189786 PMCID: PMC9842919 DOI: 10.1002/hbm.26093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 07/04/2022] [Accepted: 07/07/2022] [Indexed: 01/25/2023] Open
Abstract
Whether head size and/or biological sex influence proxies of white matter (WM) microstructure such as fractional anisotropy (FA) and mean diffusivity (MD) remains controversial. Diffusion tensor imaging (DTI) indices are also associated with age, but there are large discrepancies in the spatial distribution and timeline of age-related differences reported. The aim of this study was to evaluate the associations between intracranial volume (ICV), sex, and age and DTI indices from WM in a population-based study of healthy individuals (n = 812) aged 50-66 in the Nord-Trøndelag health survey. Semiautomated tractography and tract-based spatial statistics (TBSS) analyses were performed on the entire sample and in an ICV-matched sample of men and women. The tractography results showed a similar positive association between ICV and FA in all major WM tracts in men and women. Associations between ICV and MD, radial diffusivity and axial diffusivity were also found, but to a lesser extent than FA. The TBSS results showed that both men and women had areas of higher and lower FA when controlling for age, but after controlling for age and ICV only women had areas with higher FA. The ICV matched analysis also demonstrated that only women had areas of higher FA. Age was negatively associated with FA across the entire WM skeleton in the TBSS analysis, independent of both sex and ICV. Combined, these findings demonstrated that both ICV and sex contributed to variation in DTI indices and emphasized the importance of considering ICV as a covariate in DTI analysis.
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Affiliation(s)
- Live Eikenes
- Department of Circulation and Medical ImagingNorwegian University of Science and TechnologyTrondheimNorway
| | - Eelke Visser
- Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUK,Donders InstituteRadboud University Nijmegen Medical CentreNijmegenThe Netherlands
| | - Torgil Vangberg
- Department of Clinical MedicineUiT The Arctic University of NorwayTromsøNorway,PET CenterUniversity Hospital North NorwayTromsøNorway
| | - Asta K. Håberg
- Department of NeuroscienceNorwegian University of Science and TechnologyTrondheimNorway,Department of Diagnostic Imaging, MR‐CenterSt. Olav's University HospitalTrondheimNorway
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19
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Pagni BA, Walsh MJ, Ofori E, Chen K, Sullivan G, Alvar J, Monahan L, Guerithault N, Delaney S, Braden BB. Effects of age on the hippocampus and verbal memory in adults with autism spectrum disorder: Longitudinal versus cross-sectional findings. Autism Res 2022; 15:1810-1823. [PMID: 36053945 PMCID: PMC9561078 DOI: 10.1002/aur.2797] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Accepted: 08/08/2022] [Indexed: 11/07/2022]
Abstract
Research studying aging in adults with autism spectrum disorder (ASD) is growing, but longitudinal work is needed. Autistic adults have increased risk of dementia, altered hippocampal volumes and fornix integrity, and verbal memory difficulties compared with neurotypical (NT) adults. This study examined longitudinal aging in middle-age adults with ASD versus a matched NT group, and compared findings with cross-sectional age effects across a broad adult age range. Participants were 194 adults with (n = 106; 74 male) and without (n = 88; 52 male) ASD, ages 18-71. Participants (n = 45; 40-70 age range) with two visits (2-3 years apart) were included in a longitudinal analysis. Hippocampal volume, fornix fractional anisotropy (FA), and verbal memory were measured via T1-weighted MRI, diffusion tensor imaging, and the Rey Auditory Verbal Learning Test, respectively. Longitudinal mixed models were used for hippocampal system variables and reliable change index categories were used for Auditory Verbal Learning Test analyses. Multivariate regression was used for cross-sectional analyses. Middle-age adults with ASD had greater longitudinal hippocampal volume loss and were more likely to show clinically meaningful decline in short-term memory, compared with NT. In contrast, cross-sectional associations between increasing age and worsening short-term memory were identified in NT, but not autistic adults. Reduced fornix FA and long-term memory in ASD were found across the broad cross-sectional age range. These preliminary longitudinal findings suggest accelerated hippocampal volume loss in ASD and slightly higher rates of clinically-meaningful decline in verbal short-term memory. Contradictory cross-sectional and longitudinal results underscore the importance of longitudinal aging research in autistic adults. LAY SUMMARY: Autistic adults have increased risk of dementia, differences in brain memory structures, and difficulty with memory compared with neurotypical (NT) adults. However, there are no publications that follow the same middle-age autistic adults over time to see how their brain and memory change. Our preliminary findings in a small middle-age autism sample suggest a key memory brain structure, the hippocampus, may shrink faster over 2-3 years compared with NT, and short-term memory may become more challenging for some. Across a broad adult range, autistic adults also had reduced integrity of connections to the hippocampus and greater challenges with long-term memory. In our larger sample across a broad age range, the results did not hint at this aforementioned pattern of accelerated aging. This underscores the importance of more aging research in autism, and especially research where people are followed over time.
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Affiliation(s)
- Broc A. Pagni
- Arizona State University, College of Health Solutions, Lattie F. Coor Hall, Room 3407, 976 S Forest Mall, Tempe, AZ, 85281
| | - Melissa J.M. Walsh
- Arizona State University, College of Health Solutions, Lattie F. Coor Hall, Room 3407, 976 S Forest Mall, Tempe, AZ, 85281
| | - Edward Ofori
- Arizona State University, College of Health Solutions, Lattie F. Coor Hall, Room 3407, 976 S Forest Mall, Tempe, AZ, 85281
| | - Kewei Chen
- Banner Alzheimer’s Institute, 901 E. Willetta St, Phoenix, AZ
| | - Georgia Sullivan
- Arizona State University, College of Health Solutions, Lattie F. Coor Hall, Room 3407, 976 S Forest Mall, Tempe, AZ, 85281
| | - Jocelyn Alvar
- Arizona State University, College of Health Solutions, Lattie F. Coor Hall, Room 3407, 976 S Forest Mall, Tempe, AZ, 85281
| | - Leanna Monahan
- Arizona State University, College of Health Solutions, Lattie F. Coor Hall, Room 3407, 976 S Forest Mall, Tempe, AZ, 85281
| | - Nicolas Guerithault
- Arizona State University, College of Health Solutions, Lattie F. Coor Hall, Room 3407, 976 S Forest Mall, Tempe, AZ, 85281
| | - Shanna Delaney
- Arizona State University, College of Health Solutions, Lattie F. Coor Hall, Room 3407, 976 S Forest Mall, Tempe, AZ, 85281
| | - B. Blair Braden
- Arizona State University, College of Health Solutions, Lattie F. Coor Hall, Room 3407, 976 S Forest Mall, Tempe, AZ, 85281
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20
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Bouhrara M, Triebswetter C, Kiely M, Bilgel M, Dolui S, Erus G, Meirelles O, Bryan NR, Detre JA, Launer LJ. Association of Cerebral Blood Flow With Longitudinal Changes in Cerebral Microstructural Integrity in the Coronary Artery Risk Development in Young Adults (CARDIA) Study. JAMA Netw Open 2022; 5:e2231189. [PMID: 36094503 PMCID: PMC9468885 DOI: 10.1001/jamanetworkopen.2022.31189] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
IMPORTANCE Decreased cerebral tissue integrity and cerebral blood flow (CBF) are features of neurodegenerative diseases. Brain tissue maintenance is an energy-demanding process, making it particularly sensitive to hypoperfusion. However, little is known about the association between blood flow and brain microstructural integrity, including in normative aging. OBJECTIVE To assess associations between CBF and changes in cerebral tissue integrity in white matter and gray matter brain regions. DESIGN, SETTING, AND PARTICIPANTS In this longitudinal cohort study, magnetic resonance imaging was performed on 732 healthy adults from the Coronary Artery Risk Development in Young Adults (CARDIA) study, a prospective longitudinal study (baseline age of 18-30 years) that examined participants up to 8 times during 30 years (1985-1986 to 2015-2016). Cerebral blood flow was measured at baseline (year 25 of the CARDIA study), and changes in diffusion tensor indices of fractional anisotropy (FA) and mean diffusivity (MD), measures of microstructural tissue integrity, were measured at both baseline and after approximately 5 years of follow-up (year 30). Analyses were conducted from November 5, 2020, to January 29, 2022. MAIN OUTCOMES AND MEASURES Automated algorithms and linear mixed-effects statistical models were used to evaluate the associations between CBF at baseline and changes in FA or MD. RESULTS After exclusion of participants with missing or low-quality data, 654 at baseline (342 women; mean [SD] age, 50.3 [3.5] years) and 433 at follow-up (230 women; mean [SD] age, 55.1 [3.5] years) were scanned for CBF or FA and MD imaging. In the baseline cohort, 247 participants were Black (37.8%) and 394 were White (60.2%); in the follow-up cohort, 156 were Black (36.0%) and 277 were White (64.0%). Cross-sectionally, FA and MD were associated with CBF in most regions evaluated, with lower CBF values associated with lower FA or higher MD values, including the frontal white matter lobes (for CBF and MD: mean [SE] β = -1.4 [0.5] × 10-6; for CBF and FA: mean [SE] β = 2.9 [1.0] × 10-4) and the parietal white matter lobes (for CBF and MD: mean [SE] β = -2.4 [0.6] × 10-6; for CBF and FA: mean [SE] β = 4.4 [1.1] × 10-4). Lower CBF values at baseline were also significantly associated with steeper regional decreases in FA or increases in MD in most brain regions investigated, including the frontal (for CBF and MD: mean [SE] β = -1.1 [0.6] × 10-6; for CBF and FA: mean [SE] β = 2.9 [1.0] × 10-4) and parietal lobes (for CBF and MD: mean [SE] β = -1.5 [0.7] × 10-6; for CBF and FA: mean [SE] β = 4.4 [1.1] × 10-4). CONCLUSIONS AND RELEVANCE Results of this longitudinal cohort study of the association between CBF and diffusion tensor imaging metrics suggest that blood flow may be significantly associated with brain tissue microstructure. This work may lay the foundation for investigations to clarify the nature of early brain damage in neurodegeneration. Such studies may lead to new neuroimaging biomarkers of brain microstructure and function for disease progression.
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Affiliation(s)
- Mustapha Bouhrara
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, Maryland
| | - Curtis Triebswetter
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, Maryland
| | - Matthew Kiely
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, Maryland
| | - Murat Bilgel
- Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, Maryland
| | - Sudipto Dolui
- Department of Radiology, University of Pennsylvania, Philadelphia
| | - Guray Erus
- Center for Biomedical Image Computing and Analytics, University of Pennsylvania, Philadelphia
| | - Osorio Meirelles
- Laboratory of Epidemiology and Population Science, National Institute on Aging, National Institutes of Health, Baltimore, Maryland
| | - Nick R. Bryan
- Department of Diagnostic Medicine, University of Texas, Austin
| | - John A. Detre
- Department of Radiology, University of Pennsylvania, Philadelphia
- Department of Neurology, University of Pennsylvania, Philadelphia
| | - Lenore J. Launer
- Laboratory of Epidemiology and Population Science, National Institute on Aging, National Institutes of Health, Baltimore, Maryland
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21
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Chard J, Cook R, Press C. Impaired sensitivity to spatial configurations in healthy aging. Cortex 2022; 155:347-356. [DOI: 10.1016/j.cortex.2022.05.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 03/16/2022] [Accepted: 05/16/2022] [Indexed: 11/03/2022]
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22
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Boban J, Thurnher MM, Boban N, Law M, Jahanshad N, Nir TM, Lendak DF, Kozic D. Gradient Patterns of Age-Related Diffusivity Changes in Cerebral White Matter. Front Neurol 2022; 13:870909. [PMID: 35720102 PMCID: PMC9201287 DOI: 10.3389/fneur.2022.870909] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 04/25/2022] [Indexed: 11/24/2022] Open
Abstract
The current concept of brain aging proposes three gradient patterns of changes in white matter that occur during healthy brain aging: antero-posterior, supero-inferior, and the myelodegeneration-retrogenesis (or the “last-in-first-out”) concept. The aim of this study was to correlate white matter diffusivity measures (fractional anisotropy-FA, mean diffusivity-MD, radial diffusivity-RD, and axial diffusivity-AD) in healthy volunteers with chronological age and education level, in order to potentially incorporate the findings with proposed patterns of physiological brain aging. The study was performed on 75 healthy participants of both sexes, with an average age of 37.32 ± 11.91 years underwent brain magnetic resonance imaging (MRI) with diffusion tensor imaging (DTI). DTI was performed using tract-based spatial statistics (TBSS), with the analysis of four parameters: FA, MD, RD, and AD. Skeletonized measures were averaged in 29 regions of interest in white matter. Correlations between age and DTI measures and between education-level and DTI measures were performed using Pearson's correlation test. To correct for multiple comparisons, we applied a Bonferroni correction to the p-values. Significance was set at p ≤ 0.001. A significant negative correlation of FA with age was observed in posterior thalamic radiation (PTR) (p< 0.001). A significant positive correlation between age and MD was observed in sagittal stratum (SS) (p< 0.001), between age and RD in PTR, SS, and retrolenticular internal capsule (p< 0.001), and between age and AD in the body of the corpus callosum (p< 0.001). There were no significant correlations of DTI parameters with educational level. According to our study, RD showed the richest correlations with age, out of all DTI metrics. FA, MD, and RD showed significant changes in the diffusivity of projection fibers, while AD presented diffusivity changes in the commissural fibers. The observed heterogeneity in diffusivity changes across the brain cannot be explained by a single aging gradient pattern, since it seems that different patterns of degradation are true for different fiber tracts that no currently available theory can globally explain age-related changes in the brain. Additional factors, such as the effect of somatosensory decline, should be included as one of the important covariables to the existing patterns.
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Affiliation(s)
- Jasmina Boban
- Faculty of Medicine Novi Sad, Department of Radiology, University of Novi Sad, Novi Sad, Serbia
- Vojvodina Institute of Oncology, Center for Diagnostic Imaging, Sremska Kamenica, Serbia
- *Correspondence: Jasmina Boban
| | - Majda M. Thurnher
- Department for Biomedical Imaging and Image-guided Therapy, Medical University Vienna, Vienna, Austria
| | - Nikola Boban
- Clinical Center of Vojvodina, Center for Radiology, Novi Sad, Serbia
| | - Meng Law
- Department for Neuroscience, The Alfred Centre, Central Clinical School, Monash University, Melbourne, VIC, United States
| | - Neda Jahanshad
- Imaging Genetics Center, Mark and Mary Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California, Marina del Rey, CA, United States
| | - Talia M. Nir
- Imaging Genetics Center, Mark and Mary Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California, Marina del Rey, CA, United States
| | - Dajana F. Lendak
- Faculty of Medicine Novi Sad, Department of Infectious Diseases, University of Novi Sad, Novi Sad, Serbia
- Clinical Center of Vojvodina, Clinic for Infectious Diseases, Novi Sad, Serbia
| | - Dusko Kozic
- Faculty of Medicine Novi Sad, Department of Radiology, University of Novi Sad, Novi Sad, Serbia
- Vojvodina Institute of Oncology, Center for Diagnostic Imaging, Sremska Kamenica, Serbia
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23
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Braverman ER, Dennen CA, Gold MS, Bowirrat A, Gupta A, Baron D, Roy AK, Smith DE, Cadet JL, Blum K. Proposing a “Brain Health Checkup (BHC)” as a Global Potential “Standard of Care” to Overcome Reward Dysregulation in Primary Care Medicine: Coupling Genetic Risk Testing and Induction of “Dopamine Homeostasis”. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19095480. [PMID: 35564876 PMCID: PMC9099927 DOI: 10.3390/ijerph19095480] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 04/26/2022] [Accepted: 04/28/2022] [Indexed: 12/27/2022]
Abstract
In 2021, over 100,000 people died prematurely from opioid overdoses. Neuropsychiatric and cognitive impairments are underreported comorbidities of reward dysregulation due to genetic antecedents and epigenetic insults. Recent genome-wide association studies involving millions of subjects revealed frequent comorbidity with substance use disorder (SUD) in a sizeable meta-analysis of depression. It found significant associations with the expression of NEGR1 in the hypothalamus and DRD2 in the nucleus accumbens, among others. However, despite the rise in SUD and neuropsychiatric illness, there are currently no standard objective brain assessments being performed on a routine basis. The rationale for encouraging a standard objective Brain Health Check (BHC) is to have extensive data available to treat clinical syndromes in psychiatric patients. The BHC would consist of a group of reliable, accurate, cost-effective, objective assessments involving the following domains: Memory, Attention, Neuropsychiatry, and Neurological Imaging. Utilizing primarily PUBMED, over 36 years of virtually all the computerized and written-based assessments of Memory, Attention, Psychiatric, and Neurological imaging were reviewed, and the following assessments are recommended for use in the BHC: Central Nervous System Vital Signs (Memory), Test of Variables of Attention (Attention), Millon Clinical Multiaxial Inventory III (Neuropsychiatric), and Quantitative Electroencephalogram/P300/Evoked Potential (Neurological Imaging). Finally, we suggest continuing research into incorporating a new standard BHC coupled with qEEG/P300/Evoked Potentials and genetically guided precision induction of “dopamine homeostasis” to diagnose and treat reward dysregulation to prevent the consequences of dopamine dysregulation from being epigenetically passed on to generations of our children.
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Affiliation(s)
- Eric R. Braverman
- The Kenneth Blum Institute on Behavior & Neurogenetics, Austin, TX 78701, USA; (E.R.B.); (C.A.D.)
| | - Catherine A. Dennen
- The Kenneth Blum Institute on Behavior & Neurogenetics, Austin, TX 78701, USA; (E.R.B.); (C.A.D.)
| | - Mark S. Gold
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO 63110, USA;
- Department of Psychiatry, Tulane School of Medicine, New Orleans, LA 70112, USA;
| | - Abdalla Bowirrat
- Department of Molecular Biology, Adelson School of Medicine, Ariel University, Ariel 40700, Israel;
| | - Ashim Gupta
- Future Biologics, Lawrenceville, GA 30043, USA;
| | - David Baron
- Division of Addiction Research & Education, Center for Psychiatry, Medicine & Primary Care (Office of Provost), Western University Health Sciences, Pomona, CA 91766, USA;
| | - A. Kenison Roy
- Department of Psychiatry, Tulane School of Medicine, New Orleans, LA 70112, USA;
| | - David E. Smith
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, CA 94158, USA;
| | - Jean Lud Cadet
- The Molecular Neuropsychiatry Research Branch, NIH National Institute on Drug Abuse, Baltimore, MD 21224, USA;
| | - Kenneth Blum
- The Kenneth Blum Institute on Behavior & Neurogenetics, Austin, TX 78701, USA; (E.R.B.); (C.A.D.)
- Division of Addiction Research & Education, Center for Psychiatry, Medicine & Primary Care (Office of Provost), Western University Health Sciences, Pomona, CA 91766, USA;
- Correspondence:
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Lewis JD, O’Reilly C, Bock E, Theilmann RJ, Townsend J. Aging-Related Differences in Structural and Functional Interhemispheric Connectivity. Cereb Cortex 2022; 32:1379-1389. [PMID: 34496021 PMCID: PMC9190305 DOI: 10.1093/cercor/bhab275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 07/18/2021] [Accepted: 07/19/2021] [Indexed: 11/13/2022] Open
Abstract
There is substantial evidence of age-related declines in anatomical connectivity during adulthood, with associated alterations in functional connectivity. But the relation of those functional alterations to the structural reductions is unclear. The complexities of both the structural and the functional connectomes make it difficult to determine such relationships. We pursue this question with methods, based on animal research, that specifically target the interhemispheric connections between the visual cortices. We collect t1- and diffusion-weighted imaging data from which we assess the integrity of the white matter interconnecting the bilateral visual cortices. Functional connectivity between the visual cortices is measured with electroencephalography during the presentation of drifting sinusoidal gratings that agree or conflict across hemifields. Our results show age-related reductions in the integrity of the white matter interconnecting the visual cortices, and age-related increases in the difference in functional interhemispheric lagged coherence between agreeing versus disagreeing visual stimuli. We show that integrity of the white matter in the splenium of the corpus callosum predicts the differences in lagged coherence for the agreeing versus disagreeing stimuli; and that this relationship is mediated by age. These results give new insight into the causal relationship between age and functional connectivity.
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Affiliation(s)
- John D Lewis
- McGill Centre for Integrative Neuroscience, Montreal Neurological Institute, McGill University, Montreal, Quebec, H3A 2B4, Canada
| | - Christian O’Reilly
- Azrieli Centre for Autism Research, McGill University, Montreal, Quebec, H3A 2B4, Canada
| | - Elizabeth Bock
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, QC, H3A 2B4, Canada
| | | | - Jeanne Townsend
- Department of Neurosciences, UC San Diego, La Jolla, CA 92093, USA
- Research on Aging and Development Laboratory, UC San Diego, La Jolla, CA 92037, USA
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Liu K, Wang X, Zhang T, Wang W, Li R, Lu L, Deng Y, Xu K, Kwok T. Cortical Short-Range Fiber Connectivity and Its Association With Deep Brain White Matter Hyperintensities in Older Diabetic People With Low Serum Vitamin B12. Front Aging Neurosci 2022; 14:754997. [PMID: 35401148 PMCID: PMC8990772 DOI: 10.3389/fnagi.2022.754997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Accepted: 03/03/2022] [Indexed: 11/25/2022] Open
Abstract
Although previous studies have indicated that older people with diabetes mellitus (DM) had an approximately two times larger white matter hyperintensity (WMH) load than those without DM, the influence of WMHs on cognition is uncertain and inconsistent in the literature. It is unclear whether the short-range fibers in the juxtacortical region, traditionally considered to be spared from WMH pathology, are enhanced as an adaptive response to deep WM degeneration in older diabetic people with normal cognition. Moreover, the specific effect of vitamin B12 deficiency, commonly accompanied by DM, remains to be investigated. This study implemented a specialized analysis of the superficial cortical short-range fiber connectivity density (SFiCD) based on a data-driven framework in 70 older individuals with DM and low serum vitamin B12. Moreover, the effects of time and vitamin B12 supplementation were assessed based on a randomized placebo-controlled trial in 59 individuals. The results demonstrated a higher SFiCD in diabetic individuals with a higher deep WMH load. Additionally, a significant interaction between DWMH load and homocysteine on SFiCD was found. During the 27-month follow-up period, a longitudinal increase in the SFiCD was observed in the bilateral frontal cortices. However, the observed longitudinal SFiCD change was not dependent on vitamin B12 supplementation; thus, the specific reason for the longitudinal cortical short fiber densification may need further study. Overall, these findings may help us better understand the neurobiology of brain plasticity in older patients with DM, as well as the interplay among DM, WMH, and vitamin B12 deficiency.
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Affiliation(s)
- Kai Liu
- Department of Radiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou Medical University, Xuzhou, China
| | - Xiaopeng Wang
- Department of Neurology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Teng Zhang
- Department of Nuclear Medicine and PET-CT Center, The Second Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Wei Wang
- Department of Radiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou Medical University, Xuzhou, China
| | - Ruohan Li
- Department of Radiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou Medical University, Xuzhou, China
| | - Li Lu
- Department of Radiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou Medical University, Xuzhou, China
| | - Yanjia Deng
- School of Medical Imaging, Xuzhou Medical University, Xuzhou, China
- *Correspondence: Yanjia Deng,
| | - Kai Xu
- Department of Radiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou Medical University, Xuzhou, China
- Kai Xu,
| | - Timothy Kwok
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
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White-Matter Integrity and Working Memory: Links to Aging and Dopamine-Related Genes. eNeuro 2022; 9:ENEURO.0413-21.2022. [PMID: 35346961 PMCID: PMC9014983 DOI: 10.1523/eneuro.0413-21.2022] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 01/22/2022] [Accepted: 02/07/2022] [Indexed: 11/21/2022] Open
Abstract
Working memory, a core function underlying many higher-level cognitive processes, requires cooperation of multiple brain regions. White matter refers to myelinated axons, which are critical to interregional brain communication. Past studies on the association between white-matter integrity and working memory have yielded mixed findings. Using voxelwise tract-based spatial statistics analysis, we investigated this relationship in a sample of 328 healthy adults from 25 to 80 years of age. Given the important role of dopamine (DA) in working-memory functioning and white matter, we also analyzed the effects of dopamine-related genes on them. There were associations between white-matter integrity and working memory in multiple tracts, indicating that working-memory functioning relies on global connections between different brain areas across the adult life span. Moreover, a mediation analysis suggested that white-matter integrity contributes to age-related differences in working memory. Finally, there was an effect of the COMT Val158Met polymorphism on white-matter integrity, such that Val/Val carriers had lower fractional anisotropy values than any Met carriers in the internal capsule, corona radiata, and posterior thalamic radiation. As this polymorphism has been associated with dopaminergic tone in the prefrontal cortex, this result provides evidence for a link between DA neurotransmission and white matter. Together, the results support a link between white-matter integrity and working memory, and provide evidence for its interplay with age- and DA-related genes.
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Andersson P, Li X, Persson J. The association between control of interference and white-matter integrity: A cross-sectional and longitudinal investigation. Neurobiol Aging 2022; 114:49-60. [DOI: 10.1016/j.neurobiolaging.2022.03.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 02/26/2022] [Accepted: 03/01/2022] [Indexed: 12/27/2022]
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Kiely M, Triebswetter C, Cortina LE, Gong Z, Alsameen MH, Spencer RG, Bouhrara M. Insights into human cerebral white matter maturation and degeneration across the adult lifespan. Neuroimage 2022; 247:118727. [PMID: 34813969 PMCID: PMC8792239 DOI: 10.1016/j.neuroimage.2021.118727] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 10/15/2021] [Accepted: 11/12/2021] [Indexed: 01/01/2023] Open
Abstract
White matter (WM) microstructural properties change across the adult lifespan and with neuronal diseases. Understanding microstructural changes due to aging is paramount to distinguish them from neuropathological changes. Conducted on a large cohort of 147 cognitively unimpaired subjects, spanning a wide age range of 21 to 94 years, our study evaluated sex- and age-related differences in WM microstructure. Specifically, we used diffusion tensor imaging (DTI) magnetic resonance imaging (MRI) indices, sensitive measures of myelin and axonal density in WM, and myelin water fraction (MWF), a measure of the fraction of the signal of water trapped within the myelin sheets, to probe these differences. Furthermore, we examined regional correlations between MWF and DTI indices to evaluate whether the DTI metrics provide information complementary to MWF. While sexual dimorphism was, overall, nonsignificant, we observed region-dependent differences in MWF, that is, myelin content, and axonal density with age and found that both exhibit nonlinear, but distinct, associations with age. Furthermore, DTI indices were moderately correlated with MWF, indicating their good sensitivity to myelin content as well as to other constituents of WM tissue such as axonal density. The microstructural differences captured by our MRI metrics, along with their weak to moderate associations with MWF, strongly indicate the potential value of combining these outcome measures in a multiparametric approach. Furthermore, our results support the last-in-first-out and the gain-predicts-loss hypotheses of WM maturation and degeneration. Indeed, our results indicate that the posterior WM regions are spared from neurodegeneration as compared to anterior regions, while WM myelination follows a temporally symmetric time course across the adult life span.
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Affiliation(s)
- Matthew Kiely
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, 21224 MD, USA
| | - Curtis Triebswetter
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, 21224 MD, USA
| | - Luis E Cortina
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, 21224 MD, USA
| | - Zhaoyuan Gong
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, 21224 MD, USA
| | - Maryam H Alsameen
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, 21224 MD, USA
| | - Richard G Spencer
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, 21224 MD, USA
| | - Mustapha Bouhrara
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, 21224 MD, USA.
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29
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Saboo KV, Hu C, Varatharajah Y, Przybelski SA, Reid RI, Schwarz CG, Graff-Radford J, Knopman DS, Machulda MM, Mielke MM, Petersen RC, Arnold PM, Worrell GA, Jones DT, Jack Jr CR, Iyer RK, Vemuri P. Deep learning identifies brain structures that predict cognition and explain heterogeneity in cognitive aging. Neuroimage 2022; 251:119020. [PMID: 35196565 PMCID: PMC9045384 DOI: 10.1016/j.neuroimage.2022.119020] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 01/20/2022] [Accepted: 02/17/2022] [Indexed: 12/02/2022] Open
Abstract
Specific brain structures (gray matter regions and white matter tracts) play a dominant role in determining cognitive decline and explain the heterogeneity in cognitive aging. Identification of these structures is crucial for screening of older adults at risk of cognitive decline. Using deep learning models augmented with a model-interpretation technique on data from 1432 Mayo Clinic Study of Aging participants, we identified a subset of brain structures that were most predictive of individualized cognitive trajectories and indicative of cognitively resilient vs. vulnerable individuals. Specifically, these structures explained why some participants were resilient to the deleterious effects of elevated brain amyloid and poor vascular health. Of these, medial temporal lobe and fornix, reflective of age and pathology-related degeneration, and corpus callosum, reflective of inter-hemispheric disconnection, accounted for 60% of the heterogeneity explained by the most predictive structures. Our results are valuable for identifying cognitively vulnerable individuals and for developing interventions for cognitive decline.
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Porat S, Sibilia F, Yoon J, Shi Y, Dahl MJ, Werkle-Bergner M, Düzel S, Bodammer N, Lindenberger U, Kühn S, Mather M. Age Differences in Diffusivity in the Locus Coeruleus and its Ascending Noradrenergic Tract. Neuroimage 2022; 251:119022. [PMID: 35192943 PMCID: PMC9183949 DOI: 10.1016/j.neuroimage.2022.119022] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 02/16/2022] [Accepted: 02/17/2022] [Indexed: 12/11/2022] Open
Abstract
The noradrenergic locus coeruleus (LC) is a small brainstem nucleus that promotes arousal and attention. Recent studies have examined the microstructural properties of the LC using diffusion-weighted magnetic resonance imaging and found unexpected age-related differences in fractional anisotropy - a measure of white matter integrity. Here, we used two datasets (Berlin Aging Study-II, N = 301, the Leipzig Study for Mind-Body-Emotion Interactions, N = 220), to replicate published findings and expand them by investigating diffusivity in the LC’s ascending noradrenergic bundle. In younger adults, LC fractional anisotropy was significantly lower, compared to older adults. However, in the LC’s ascending noradrenergic bundle, we observed significantly higher fractional anisotropy in younger adults, relative to older adults. These findings indicate that diffusivity in the LC versus the ascending noradrenergic bundle are both susceptible to structural changes in aging that have opposing effects on fractional anisotropy.
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31
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Cortina LE, Kim RW, Kiely M, Triebswetter C, Gong Z, Alsameen MH, Bouhrara M. Cerebral aggregate g-ratio mapping using magnetic resonance relaxometry and diffusion tensor imaging to investigate sex and age-related differences in white matter microstructure. Magn Reson Imaging 2022; 85:87-92. [PMID: 34678436 PMCID: PMC8629921 DOI: 10.1016/j.mri.2021.10.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 10/15/2021] [Accepted: 10/16/2021] [Indexed: 01/03/2023]
Abstract
Axonal demyelination is a cardinal feature of aging and age-related diseases. The g-ratio, mathematically defined as the inner-to-outer diameter of a myelinated axon, is used as a structural index of optimal axonal myelination and has been shown to represent a sensitive imaging biomarker of microstructural integrity. Several magnetic resonance imaging (MRI) methods for whole-brain mapping of aggregate g-ratio have been introduced. Computation of the aggerate g-ratio requires estimates of the myelin volume fraction (MVF) and the axonal volume fraction (AVF). While accurate determinations of MVF and AVF can be obtained through multicomponent relaxometry or diffusion analyses, respectively, these methods require lengthy acquisition times making their implementation challenging in a clinical context. Therefore, any attempt to overcome this drawback is needed. Expanding on our previous work, we introduced a new MRI method for whole-brain mapping of aggregate g-ratio. This new approach is based on the use of a single-shell diffusion for AVF determination, reducing the acquisition time by approximately ~10 min from our recently introduced approach, while offering the possibility to investigate g-ratio differences in previous studies with existing data for MVF mapping and single-shell diffusion data for AVF mapping. Our comparison analysis indicates that our newly derived aggregate g-ratio values were similar to those derived from our previous method, which requires a longer acquisition time. Further, in agreement with our previous observations, we found quadratic U-shaped relationships between aggregate g-ratio and age in this much larger study cohort. However, our results show that sexual dimorphism in g-ratio was not significant in any brain region investigated.
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Affiliation(s)
| | | | | | | | | | | | - Mustapha Bouhrara
- Corresponding author: Mustapha Bouhrara, PhD., MRPAD Unit, National Institute on Aging (NIA), National Institutes of Health (NIH), Intramural Research Program, BRC 05C-222, 251 Bayview Boulevard, Baltimore, MD 21224, USA. Tel: 410-558-8541,
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32
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Rahmani F, Wang Q, McKay NS, Keefe S, Hantler N, Hornbeck R, Wang Y, Hassenstab J, Schindler S, Xiong C, Morris JC, Benzinger TL, Raji CA. Sex-Specific Patterns of Body Mass Index Relationship with White Matter Connectivity. J Alzheimers Dis 2022; 86:1831-1848. [PMID: 35180116 PMCID: PMC9108572 DOI: 10.3233/jad-215329] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/31/2022] [Indexed: 11/15/2022]
Abstract
BACKGROUND Obesity is an increasingly recognized modifiable risk factor for Alzheimer's disease (AD). Increased body mass index (BMI) is related to distinct changes in white matter (WM) fiber density and connectivity. OBJECTIVE We investigated whether sex differentially affects the relationship between BMI and WM structural connectivity. METHODS A cross-sectional sample of 231 cognitively normal participants were enrolled from the Knight Alzheimer Disease Research Center. Connectome analyses were done with diffusion data reconstructed using q-space diffeomorphic reconstruction to obtain the spin distribution function and tracts were selected using a deterministic fiber tracking algorithm. RESULTS We identified an inverse relationship between higher BMI and lower connectivity in the associational fibers of the temporal lobe in overweight and obese men. Normal to overweight women showed a significant positive association between BMI and connectivity in a wide array of WM fibers, an association that reversed in obese and morbidly obese women. Interaction analyses revealed that with increasing BMI, women showed higher WM connectivity in the bilateral frontoparietal and parahippocampal parts of the cingulum, while men showed lower connectivity in right sided corticostriatal and corticopontine tracts. Subgroup analyses demonstrated comparable results in participants with and without positron emission tomography or cerebrospinal fluid evidence of brain amyloidosis, indicating that the relationship between BMI and structural connectivity in men and women is independent of AD biomarker status. CONCLUSION BMI influences structural connectivity of WM differently in men and women across BMI categories and this relationship does not vary as a function of preclinical AD.
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Affiliation(s)
- Farzaneh Rahmani
- Mallinckrodt Institute of Radiology, Division of Neuroradiology, Washington University in St. Louis, St. Louis, MO, USA
| | - Qing Wang
- Mallinckrodt Institute of Radiology, Division of Neuroradiology, Washington University in St. Louis, St. Louis, MO, USA
| | - Nicole S. McKay
- Mallinckrodt Institute of Radiology, Division of Neuroradiology, Washington University in St. Louis, St. Louis, MO, USA
| | - Sarah Keefe
- Mallinckrodt Institute of Radiology, Division of Neuroradiology, Washington University in St. Louis, St. Louis, MO, USA
| | - Nancy Hantler
- Mallinckrodt Institute of Radiology, Division of Neuroradiology, Washington University in St. Louis, St. Louis, MO, USA
| | - Russ Hornbeck
- Mallinckrodt Institute of Radiology, Division of Neuroradiology, Washington University in St. Louis, St. Louis, MO, USA
| | - Yong Wang
- Mallinckrodt Institute of Radiology, Division of Neuroradiology, Washington University in St. Louis, St. Louis, MO, USA
| | - Jason Hassenstab
- Mallinckrodt Institute of Radiology, Division of Neuroradiology, Washington University in St. Louis, St. Louis, MO, USA
| | - Suzanne Schindler
- Mallinckrodt Institute of Radiology, Division of Neuroradiology, Washington University in St. Louis, St. Louis, MO, USA
- Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA
| | - Chengjie Xiong
- Mallinckrodt Institute of Radiology, Division of Neuroradiology, Washington University in St. Louis, St. Louis, MO, USA
| | - John C. Morris
- Mallinckrodt Institute of Radiology, Division of Neuroradiology, Washington University in St. Louis, St. Louis, MO, USA
- Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA
- Charles F. and Joanne Knight Alzheimer Disease Research Center (Knight ADRC), Washington University, St. Louis, MO, USA
| | - Tammie L.S. Benzinger
- Mallinckrodt Institute of Radiology, Division of Neuroradiology, Washington University in St. Louis, St. Louis, MO, USA
- Charles F. and Joanne Knight Alzheimer Disease Research Center (Knight ADRC), Washington University, St. Louis, MO, USA
| | - Cyrus A. Raji
- Mallinckrodt Institute of Radiology, Division of Neuroradiology, Washington University in St. Louis, St. Louis, MO, USA
- Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA
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Zhao H, Cheng J, Liu T, Jiang J, Koch F, Sachdev PS, Basser PJ, Wen W. Orientational changes of white matter fibers in Alzheimer's disease and amnestic mild cognitive impairment. Hum Brain Mapp 2021; 42:5397-5408. [PMID: 34412149 PMCID: PMC8519856 DOI: 10.1002/hbm.25628] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 08/07/2021] [Indexed: 12/13/2022] Open
Abstract
White matter abnormalities represent early neuropathological events in neurodegenerative diseases such as Alzheimer's disease (AD), investigating these white matter alterations would likely provide valuable insights into pathological changes over the course of AD. Using a novel mathematical framework called "Director Field Analysis" (DFA), we investigated the geometric microstructural properties (i.e., splay, bend, twist, and total distortion) in the orientation of white matter fibers in AD, amnestic mild cognitive impairment (aMCI), and cognitively normal (CN) individuals from the Alzheimer's Disease Neuroimaging Initiative 2 database. Results revealed that AD patients had extensive orientational changes in the bilateral anterior thalamic radiation, corticospinal tract, inferior and superior longitudinal fasciculus, inferior fronto-occipital fasciculus, and uncinate fasciculus in comparison with CN. We postulate that these orientational changes of white matter fibers may be partially caused by the expansion of lateral ventricle, white matter atrophy, and gray matter atrophy in AD. In contrast, aMCI individuals showed subtle orientational changes in the left inferior longitudinal fasciculus and right uncinate fasciculus, which showed a significant association with the cognitive performance, suggesting that these regions may be preferential vulnerable to breakdown by neurodegenerative brain disorders, thereby resulting in the patients' cognitive impairment. To our knowledge, this article is the first to examine geometric microstructural changes in the orientation of white matter fibers in AD and aMCI. Our findings demonstrate that the orientational information of white matter fibers could provide novel insight into the underlying biological and pathological changes in AD and aMCI.
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Affiliation(s)
- Haichao Zhao
- Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical EngineeringBeihang UniversityBeijingChina
| | - Jian Cheng
- Beijing Advanced Innovation Center for Big Data‐Based Precision MedicineBeihang UniversityBeijingChina
| | - Tao Liu
- Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical EngineeringBeihang UniversityBeijingChina
- Beijing Advanced Innovation Center for Big Data‐Based Precision MedicineBeihang UniversityBeijingChina
| | - Jiyang Jiang
- Centre for Healthy Brain Ageing, School of Psychiatry (CHeBA)University of New South WalesSydneyNew South WalesAustralia
| | - Forrest Koch
- Centre for Healthy Brain Ageing, School of Psychiatry (CHeBA)University of New South WalesSydneyNew South WalesAustralia
| | - Perminder S. Sachdev
- Centre for Healthy Brain Ageing, School of Psychiatry (CHeBA)University of New South WalesSydneyNew South WalesAustralia
| | - Peter J. Basser
- Section on Quantitative Imaging and Tissue SciencesNIBIB, NICHD, National Institutes of HealthBethesdaMaryland
| | - Wei Wen
- Centre for Healthy Brain Ageing, School of Psychiatry (CHeBA)University of New South WalesSydneyNew South WalesAustralia
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Ingo C, Kurian S, Higgins J, Mahinrad S, Jenkins L, Gorelick P, Lloyd-Jones D, Sorond F. Vascular health and diffusion properties of normal appearing white matter in midlife. Brain Commun 2021; 3:fcab080. [PMID: 34494002 DOI: 10.1093/braincomms/fcab080] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/11/2021] [Indexed: 01/20/2023] Open
Abstract
In this study, we perform a region of interest diffusion tensor imaging and advanced diffusion complexity analysis of normal appearing white matter to determine the impact of vascular health on these diffusivity metrics in midlife adults. 77 participants (26 black, 35 female) at year 30 visit in the Coronary Artery Risk Development in Young Adults longitudinal study were scanned with an advanced diffusion-weighted imaging and fluid-attenuated inversion recovery protocol. Fractional anisotropy and non-linear diffusion complexity measures were estimated. Cumulative measures across 30 years (9 study visits) of systolic blood pressure, body mass index, glucose, smoking and cholesterol were calculated as the area under the curve from baseline up to year 30 examination. Partial correlation analyses assessed the association between cumulative vascular health measures and normal appearing white matter diffusion metrics in these participants. Midlife normal appearing white matter diffusion properties were significantly associated (P < 0.05) with cumulative exposure to vascular risk factors from young adulthood over the 30-year time period. Higher cumulative systolic blood pressure exposure was associated with increased complexity and decreased fractional anisotropy. Higher cumulative body mass index exposure was associated with decreased fractional anisotropy. Additionally, in the normal appearing white matter of black participants (P < 0.05), who exhibited a higher cumulative vascular risk exposure, fractional anisotropy was lower and complexity was higher in comparison to normal appearing white matter in white participants. Higher burden of vascular risk factor exposure from young adulthood to midlife is associated with changes in the diffusion properties of normal appearing white matter in midlife. These changes which may reflect axonal disruption, increased inflammation and/or increased glial proliferation, were primarily observed in both anterior and posterior normal appearing white matter regions of the corpus callosum. These results suggest that microstructural changes in normal appearing white matter are sensitive to vascular health during young adulthood and are possibly therapeutic targets in interventions focused on preserving white matter health across life.
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Affiliation(s)
- Carson Ingo
- Department of Neurology, Northwestern University, Chicago, IL, USA.,Department of Physical Therapy and Human Movement Sciences, Northwestern University, Chicago, IL, USA
| | - Shawn Kurian
- Department of Neurology, Northwestern University, Chicago, IL, USA
| | - James Higgins
- Department of Radiology, Northwestern University, Chicago, IL, USA
| | - Simin Mahinrad
- Department of Neurology, Northwestern University, Chicago, IL, USA
| | - Lisanne Jenkins
- Department of Psychiatry and Behavioral Sciences, Northwestern University, Chicago, IL, USA
| | - Philip Gorelick
- Department of Neurology, Northwestern University, Chicago, IL, USA
| | - Donald Lloyd-Jones
- Department of Preventive Medicine, Northwestern University, Chicago, IL, USA
| | - Farzaneh Sorond
- Department of Neurology, Northwestern University, Chicago, IL, USA
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35
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The Relations Between Physical Activity Level, Executive Function, and White Matter Microstructure in Older Adults. J Phys Act Health 2021; 18:1286-1298. [PMID: 34433700 DOI: 10.1123/jpah.2021-0012] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 04/23/2021] [Accepted: 06/12/2021] [Indexed: 11/18/2022]
Abstract
The population of older adults is increasing, indicating a need to examine factors that may prevent or mitigate age-related cognitive decline. The current study examined whether microstructural white matter characteristics mediated the relation between physical activity and executive function in older adults without any self-reported psychiatric and neurological disorders or cognitive impairment (N = 43, mean age = 73 y). Physical activity was measured by average intensity and number of steps via accelerometry. Diffusion tensor imaging was used to examine microstructural white matter characteristics, and neuropsychological testing was used to examine executive functioning. Parallel mediation models were analyzed using microstructural white matter regions of interest as mediators of the association between physical activity and executive function. Results indicated that average steps was significantly related to executive function (β = 0.0003, t = 2.829, P = .007), while moderate to vigorous physical activity was not (β = 0.0007, t = 1.772, P = .08). White matter metrics did not mediate any associations. This suggests that microstructural white matter characteristics alone may not be the mechanism by which physical activity impacts executive function in aging.
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36
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Mendez Colmenares A, Voss MW, Fanning J, Salerno EA, Gothe NP, Thomas ML, McAuley E, Kramer AF, Burzynska AZ. White matter plasticity in healthy older adults: The effects of aerobic exercise. Neuroimage 2021; 239:118305. [PMID: 34174392 DOI: 10.1016/j.neuroimage.2021.118305] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 06/22/2021] [Accepted: 06/23/2021] [Indexed: 12/15/2022] Open
Abstract
White matter deterioration is associated with cognitive impairment in healthy aging and Alzheimer's disease. It is critical to identify interventions that can slow down white matter deterioration. So far, clinical trials have failed to demonstrate the benefits of aerobic exercise on the adult white matter using diffusion Magnetic Resonance Imaging. Here, we report the effects of a 6-month aerobic walking and dance interventions (clinical trial NCT01472744) on white matter integrity in healthy older adults (n = 180, 60-79 years) measured by changes in the ratio of calibrated T1- to T2-weighted images (T1w/T2w). Specifically, the aerobic walking and social dance interventions resulted in positive changes in the T1w/T2w signal in late-myelinating regions, as compared to widespread decreases in the T1w/T2w signal in the active control. Notably, in the aerobic walking group, positive change in the T1w/T2w signal correlated with improved episodic memory performance. Lastly, intervention-induced increases in cardiorespiratory fitness did not correlate with change in the T1w/T2w signal. Together, our findings suggest that white matter regions that are vulnerable to aging retain some degree of plasticity that can be induced by aerobic exercise training. In addition, we provided evidence that the T1w/T2w signal may be a useful and broadly accessible measure for studying short-term within-person plasticity and deterioration in the adult human white matter.
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Affiliation(s)
- Andrea Mendez Colmenares
- Department of Human Development and Family Studies/Molecular, Cellular and Integrative Neurosciences, Colorado State University, Fort Collins, CO, 80523, United States; Department of Psychology/Molecular, Cellular and Integrative Neurosciences, Colorado State University, Fort Collins, CO, 80523, United States
| | - Michelle W Voss
- Department of Psychological and Brain Sciences, University of Iowa, Iowa City, IA, 52242, United States
| | - Jason Fanning
- Department of Health and Exercise Sciences, Wake Forest University, Winston-Salem, NC, 27109, United States
| | - Elizabeth A Salerno
- Division of Public Health Sciences, Department of Surgery, Washington University School of Medicine in St. Louis, St. Louis, MO, 63130, United States
| | - Neha P Gothe
- Department of Kinesiology and Community Health, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, United States
| | - Michael L Thomas
- Department of Psychology/Molecular, Cellular and Integrative Neurosciences, Colorado State University, Fort Collins, CO, 80523, United States
| | - Edward McAuley
- Department of Kinesiology and Community Health, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, United States
| | - Arthur F Kramer
- Department of Kinesiology and Community Health, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, United States; Department of Psychology, Northeastern University, Boston, MA, 02115, United States
| | - Agnieszka Z Burzynska
- Department of Psychology, Northeastern University, Boston, MA, 02115, United States.
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Bouhrara M, Cortina LE, Khattar N, Rejimon AC, Ajamu S, Cezayirli DS, Spencer RG. Maturation and degeneration of the human brainstem across the adult lifespan. Aging (Albany NY) 2021; 13:14862-14891. [PMID: 34115614 PMCID: PMC8221341 DOI: 10.18632/aging.203183] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 05/20/2021] [Indexed: 04/12/2023]
Abstract
Brainstem tissue microstructural properties change across the adult lifespan. However, studies elucidating the biological processes that govern brainstem maturation and degeneration in-vivo are lacking. In the present work, conducted on a large cohort of 140 cognitively unimpaired subjects spanning a wide age range of 21 to 94 years, we implemented a multi-parameter approach to characterize the sex- and age differences. In addition, we examined regional correlations between myelin water fraction (MWF), a direct measure of myelin content, and diffusion tensor imaging indices, and transverse and longitudinal relaxation rates to evaluate whether these metrics provide information complementary to MWF. We observed region-dependent differences in myelin content and axonal density with age and found that both exhibit an inverted U-shape association with age in several brainstem substructures. We emphasize that the microstructural differences captured by our distinct MRI metrics, along with their weak associations with MWF, strongly indicate the potential of using these outcome measures in a multi-parametric approach. Furthermore, our results support the gain-predicts-loss hypothesis of tissue maturation and degeneration in the brainstem. Indeed, our results indicate that myelination follows a temporally symmetric time course across the adult life span, while axons appear to degenerate significantly more rapidly than they mature.
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Affiliation(s)
- Mustapha Bouhrara
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Luis E. Cortina
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Nikkita Khattar
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Abinand C. Rejimon
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Samuel Ajamu
- Laboratory of Cardiovascular Science, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Defne S. Cezayirli
- Laboratory of Cardiovascular Science, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Richard G. Spencer
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
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Reduced frontal white matter microstructure in healthy older adults with low tactile recognition performance. Sci Rep 2021; 11:11689. [PMID: 34083614 PMCID: PMC8175740 DOI: 10.1038/s41598-021-90995-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 05/12/2021] [Indexed: 11/08/2022] Open
Abstract
The aging of the nervous system is a heterogeneous process. It remains a significant challenge to identify relevant markers of pathological and healthy brain aging. A central aspect of aging are decreased sensory acuities, especially because they correlate with the decline in higher cognitive functioning. Sensory and higher cognitive processing relies on information flow between distant brain areas. Aging leads to disintegration of the underlying white matter tracts. While this disintegration is assumed to contribute to higher cognitive decline, data linking structural integrity and sensory function are sparse. The investigation of their interrelation may provide valuable insight into the mechanisms of brain aging. We used a combined behavioral and neuroimaging approach and investigated to what extent changes in microstructural white matter integrity reflect performance declines in tactile pattern recognition with aging. Poor performance in older participants was related to decreased integrity in the anterior corpus callosum. Probabilistic tractography showed that this structure is connected to the prefrontal cortices. Our data point to decreased integrity in the anterior corpus callosum as a marker for advanced brain aging. The correlation between impaired tactile recognition and disintegration in frontal brain networks could provide an explanation why the decrease of sensory function predicts cognitive decline.
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Medina LD, Heffernan K, Holden S, Simpson A, Bettcher BM. Neural correlates of daily function: A pilot study of the white matter retrogenesis hypothesis and three separate performance-based functional assessments. Neuropsychology 2021; 35:103-110. [PMID: 33393804 DOI: 10.1037/neu0000649] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
OBJECTIVE Increasing evidence points to mild alterations in everyday functioning early in the course of Alzheimer's disease and related dementias (ADRD), despite prior research suggesting functional declines occur primarily in later stages. However, daily function assessment is typically accomplished with subjective self- or informant-report, which can be prone to error due to various factors. Performance-based functional assessments (PBFAs) allow for objective evaluation of daily function abilities, but little is known on their sensitivity to the earliest ADRD-related brain alterations. We aimed to determine the neural correlates of three different PBFAs in a pilot study. METHOD A total of 40 older participants (age = 70.9 ± 6.5 years; education = 17.0 ± 2.6 years; 51.5% female; 10.0% non-White; 67.5% cognitively normal) completed standardized PBFAs related to medication management (MM), finances (FIN), and communication abilities (COM). Participants underwent diffusion tensor imaging (DTI) scans, from which mean fractional anisotropy (FA) composite scores of late- (LMF) and early myelinated (EMF) fibers were calculated. Linear regression analyses controlling for age and global cognition were used to assess the relationship of PBFAs with FA. RESULTS Better performance on MM was associated with higher mean FA on LMF composite (t38 = 2.231, p = .032), while FIN and COM were not (ps > .05). PBFAs were not associated with EMF (p > .05). CONCLUSIONS Our preliminary findings demonstrate better performance on a PBFA of medication management is associated with higher FA in late-myelinated white matter tracts. Despite a small sample size, these results are consistent with growing evidence that performance-based functional assessments may be a useful tool in identifying early changes related to ADRD. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
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Affiliation(s)
| | - Kate Heffernan
- Department of Neurology, School of Medicine, University of Colorado
| | - Samantha Holden
- Department of Neurology, School of Medicine, University of Colorado
| | - Abigail Simpson
- Department of Neurology, School of Medicine, University of Colorado
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40
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Coelho A, Fernandes HM, Magalhães R, Moreira PS, Marques P, Soares JM, Amorim L, Portugal‐Nunes C, Castanho T, Santos NC, Sousa N. Reorganization of brain structural networks in aging: A longitudinal study. J Neurosci Res 2021; 99:1354-1376. [PMID: 33527512 PMCID: PMC8248023 DOI: 10.1002/jnr.24795] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 12/31/2020] [Indexed: 12/12/2022]
Abstract
Normal aging is characterized by structural and functional changes in the brain contributing to cognitive decline. Structural connectivity (SC) describes the anatomical backbone linking distinct functional subunits of the brain and disruption of this communication is thought to be one of the potential contributors for the age-related deterioration observed in cognition. Several studies already explored brain network's reorganization during aging, but most focused on average connectivity of the whole-brain or in specific networks, such as the resting-state networks. Here, we aimed to characterize longitudinal changes of white matter (WM) structural brain networks, through the identification of sub-networks with significantly altered connectivity along time. Then, we tested associations between longitudinal changes in network connectivity and cognition. We also assessed longitudinal changes in topological properties of the networks. For this, older adults were evaluated at two timepoints, with a mean interval time of 52.8 months (SD = 7.24). WM structural networks were derived from diffusion magnetic resonance imaging, and cognitive status from neurocognitive testing. Our results show age-related changes in brain SC, characterized by both decreases and increases in connectivity weight. Interestingly, decreases occur in intra-hemispheric connections formed mainly by association fibers, while increases occur mostly in inter-hemispheric connections and involve association, commissural, and projection fibers, supporting the last-in-first-out hypothesis. Regarding topology, two hubs were lost, alongside with a decrease in connector-hub inter-modular connectivity, reflecting reduced integration. Simultaneously, there was an increase in the number of provincial hubs, suggesting increased segregation. Overall, these results confirm that aging triggers a reorganization of the brain structural network.
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Affiliation(s)
- Ana Coelho
- Life and Health Sciences Research Institute (ICVS), School of MedicineUniversity of MinhoBragaPortugal
- ICVS/3B’s, PT Government Associate LaboratoryBraga/GuimarãesPortugal
- Clinical Academic Center – BragaBragaPortugal
| | - Henrique M. Fernandes
- Center for Music in the Brain (MIB)Aarhus UniversityAarhusDenmark
- Department of PsychiatryUniversity of OxfordOxfordUK
| | - Ricardo Magalhães
- Life and Health Sciences Research Institute (ICVS), School of MedicineUniversity of MinhoBragaPortugal
- ICVS/3B’s, PT Government Associate LaboratoryBraga/GuimarãesPortugal
- Clinical Academic Center – BragaBragaPortugal
| | - Pedro S. Moreira
- Life and Health Sciences Research Institute (ICVS), School of MedicineUniversity of MinhoBragaPortugal
- ICVS/3B’s, PT Government Associate LaboratoryBraga/GuimarãesPortugal
- Clinical Academic Center – BragaBragaPortugal
| | - Paulo Marques
- Life and Health Sciences Research Institute (ICVS), School of MedicineUniversity of MinhoBragaPortugal
- ICVS/3B’s, PT Government Associate LaboratoryBraga/GuimarãesPortugal
- Clinical Academic Center – BragaBragaPortugal
| | - José M. Soares
- Life and Health Sciences Research Institute (ICVS), School of MedicineUniversity of MinhoBragaPortugal
- ICVS/3B’s, PT Government Associate LaboratoryBraga/GuimarãesPortugal
- Clinical Academic Center – BragaBragaPortugal
| | - Liliana Amorim
- Life and Health Sciences Research Institute (ICVS), School of MedicineUniversity of MinhoBragaPortugal
- ICVS/3B’s, PT Government Associate LaboratoryBraga/GuimarãesPortugal
- Clinical Academic Center – BragaBragaPortugal
| | - Carlos Portugal‐Nunes
- Life and Health Sciences Research Institute (ICVS), School of MedicineUniversity of MinhoBragaPortugal
- ICVS/3B’s, PT Government Associate LaboratoryBraga/GuimarãesPortugal
- Clinical Academic Center – BragaBragaPortugal
| | - Teresa Castanho
- Life and Health Sciences Research Institute (ICVS), School of MedicineUniversity of MinhoBragaPortugal
- ICVS/3B’s, PT Government Associate LaboratoryBraga/GuimarãesPortugal
- Clinical Academic Center – BragaBragaPortugal
| | - Nadine Correia Santos
- Life and Health Sciences Research Institute (ICVS), School of MedicineUniversity of MinhoBragaPortugal
- ICVS/3B’s, PT Government Associate LaboratoryBraga/GuimarãesPortugal
- Clinical Academic Center – BragaBragaPortugal
| | - Nuno Sousa
- Life and Health Sciences Research Institute (ICVS), School of MedicineUniversity of MinhoBragaPortugal
- ICVS/3B’s, PT Government Associate LaboratoryBraga/GuimarãesPortugal
- Clinical Academic Center – BragaBragaPortugal
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Bouhrara M, Khattar N, Elango P, Resnick SM, Ferrucci L, Spencer RG. Evidence of association between obesity and lower cerebral myelin content in cognitively unimpaired adults. Int J Obes (Lond) 2021; 45:850-859. [PMID: 33483582 PMCID: PMC8009848 DOI: 10.1038/s41366-021-00749-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 12/16/2020] [Accepted: 01/07/2021] [Indexed: 01/30/2023]
Abstract
BACKGROUND Myelin loss is a central feature of several neurodegenerative diseases, including Alzheimer's disease (AD). In animal studies, a link has been established between obesity and impairment of oligodendrocyte maturation, the cells that produce and maintain myelin. Although clinical magnetic resonance imaging (MRI) studies have revealed microstructural alterations of cerebral white matter tissue in subjects with obesity, no specific myelin vs. obesity correlation studies have been performed in humans using a direct myelin content metric. OBJECTIVES To assess the association between obesity and myelin integrity in cerebral white matter using advanced MRI methodology for myelin content imaging. METHODS Studies were performed in the clinical unit of the National Institute on Aging on a cohort of 119 cognitively unimpaired adults. Using advanced MRI methodology, we measured whole-brain myelin water fraction (MWF), a marker of myelin content. Automated brain mapping algorithms and statistical models were used to evaluate the relationships between MWF and obesity, measured using the body mass index (BMI) or waist circumference (WC), in various white matter brain regions. RESULTS MWF was negatively associated with BMI or WC in all brain regions evaluated. These associations, adjusted for sex, ethnicity, and age, were statistically significant in most brain regions examined (p < 0.05), with higher BMI or WC corresponding to lower myelin content. Finally, in agreement with previous work, MWF exhibited a quadratic, inverted U-shaped, association with age; this is attributed to the process of myelination from youth through middle age, followed by demyelination afterward. CONCLUSIONS These findings suggest that obesity was significantly associated with white matter integrity, and in particular myelin content. We expect that this work will lay the foundation for further investigations to clarify the nature of myelin damage in neurodegeneration, including AD, and the effect of lifestyle factors such as diet and physical activity on myelination.
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Affiliation(s)
- Mustapha Bouhrara
- Laboratory of Clinical Investigation, National Institute
on Aging, National Institutes of Health, Baltimore, 21224 MD, USA.,†Corresponding author: Mustapha
Bouhrara, PhD., National Institutes of Health (NIH), National
Institute on Aging (NIA), Intramural Research Program, BRC 04B-117, 251 Bayview
Boulevard, Baltimore, MD 21224, USA. Tel: 410-558-8541,
| | - Nikkita Khattar
- Laboratory of Clinical Investigation, National Institute
on Aging, National Institutes of Health, Baltimore, 21224 MD, USA
| | - Palchamy Elango
- Translational Gerontology Branch, National Institute on
Aging, National Institutes of Health, Baltimore, 21224 MD, USA
| | - Susan M. Resnick
- Laboratory of Behavioral Neuroscience, National Institute
on Aging, National Institutes of Health, Baltimore, 21224 MD, USA
| | - Luigi Ferrucci
- Translational Gerontology Branch, National Institute on
Aging, National Institutes of Health, Baltimore, 21224 MD, USA
| | - Richard G. Spencer
- Laboratory of Clinical Investigation, National Institute
on Aging, National Institutes of Health, Baltimore, 21224 MD, USA
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Kavroulakis E, Simos NJ, Maris TG, Zaganas I, Panagiotakis S, Papadaki E. Evidence of Age-Related Hemodynamic and Functional Connectivity Impairment: A Resting State fMRI Study. Front Neurol 2021; 12:633500. [PMID: 33833727 PMCID: PMC8021915 DOI: 10.3389/fneur.2021.633500] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 03/01/2021] [Indexed: 11/13/2022] Open
Abstract
Purpose: To assess age-related changes in intrinsic functional brain connectivity and hemodynamics during adulthood in the context of the retrogenesis hypothesis, which states that the rate of age-related changes is higher in late-myelinating (prefrontal, lateral-posterior temporal) cerebrocortical areas as compared to early myelinating (parietal, occipital) regions. In addition, to examine the dependence of age-related changes upon concurrent subclinical depression symptoms which are common even in healthy aging. Methods: Sixty-four healthy adults (28 men) aged 23-79 years (mean 45.0, SD = 18.8 years) were examined. Resting-state functional MRI (rs-fMRI) time series were used to compute voxel-wise intrinsic connectivity contrast (ICC) maps reflecting the strength of functional connectivity between each voxel and the rest of the brain. We further used Time Shift Analysis (TSA) to estimate voxel-wise hemodynamic lead or lag for each of 22 ROIs from the automated anatomical atlas (AAL). Results: Adjusted for depression symptoms, gender and education level, reduced ICC with age was found primarily in frontal, temporal regions, and putamen, whereas the opposite trend was noted in inferior occipital cortices (p < 0.002). With the same covariates, increased hemodynamic lead with advancing age was found in superior frontal cortex and thalamus, with the opposite trend in inferior occipital cortex (p < 0.002). There was also evidence of reduced coupling between voxel-wise intrinsic connectivity and hemodynamics in the inferior parietal cortex. Conclusion: Age-related intrinsic connectivity reductions and hemodynamic changes were demonstrated in several regions-most of them part of DMN and salience networks-while impaired neurovascular coupling was, also, found in parietal regions. Age-related reductions in intrinsic connectivity were greater in anterior as compared to posterior cortices, in line with implications derived from the retrogenesis hypothesis. These effects were affected by self-reported depression symptoms, which also increased with age.
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Affiliation(s)
- Eleftherios Kavroulakis
- Department of Radiology, School of Medicine, University of Crete, University Hospital of Heraklion, Heraklion, Greece
| | - Nicholas J Simos
- Department of Electrical and Computer Engineering, Technical University of Crete, Chania, Greece.,Computational Bio-Medicine Laboratory, Institute of Computer Science, Foundation for Research and Technology - Hellas, Heraklion, Greece
| | - Thomas G Maris
- Department of Medical Physics, School of Medicine, University of Crete, University Hospital of Heraklion, Heraklion, Greece
| | - Ioannis Zaganas
- Department of Neurology, School of Medicine, University of Crete, University Hospital of Heraklion, Heraklion, Greece
| | - Simeon Panagiotakis
- Department of Internal Medicine, University Hospital of Heraklion, Heraklion, Greece
| | - Efrosini Papadaki
- Department of Radiology, School of Medicine, University of Crete, University Hospital of Heraklion, Heraklion, Greece.,Computational Bio-Medicine Laboratory, Institute of Computer Science, Foundation for Research and Technology - Hellas, Heraklion, Greece
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Matijevic S, Ryan L. Tract Specificity of Age Effects on Diffusion Tensor Imaging Measures of White Matter Health. Front Aging Neurosci 2021; 13:628865. [PMID: 33790778 PMCID: PMC8006297 DOI: 10.3389/fnagi.2021.628865] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 02/11/2021] [Indexed: 11/13/2022] Open
Abstract
Well-established literature indicates that older adults have poorer cerebral white matter integrity, as measured through diffusion tensor imaging (DTI). Age differences in DTI have been observed widely across white matter, although some tracts appear more sensitive to the effects of aging than others. Factors like APOE ε4 status and sex may contribute to individual differences in white matter integrity that also selectively impact certain tracts, and could influence DTI changes in aging. The present study explored the degree to which age, APOE ε4, and sex exerted global vs. tract specific effects on DTI metrics in cognitively healthy late middle-aged to older adults. Data from 49 older adults (ages 54–92) at two time-points separated by approximately 2.7 years were collected. DTI metrics, including fractional anisotropy (FA) and mean diffusivity (MD), were extracted from nine white matter tracts and global white matter. Results showed that across timepoints, FA and MD increased globally, with no tract-specific changes observed. Baseline age had a global influence on both measures, with increasing age associated with lower FA and higher MD. After controlling for global white matter FA, age additionally predicted FA for the genu, callosum body, inferior fronto-occipital fasciculus (IFOF), and both anterior and posterior cingulum. Females exhibited lower global FA on average compared to males. In contrast, MD was selectively elevated in the anterior cingulum and superior longitudinal fasciculus (SLF), for females compared to males. APOE ε4 status was not predictive of either measure. In summary, these results indicate that age and sex are associated with both global and tract-specific alterations to DTI metrics among a healthy older adult cohort. Older women have poorer white matter integrity compared to older men, perhaps related to menopause-induced metabolic changes. While age-related alterations to white matter integrity are global, there is substantial variation in the degree to which tracts are impacted, possibly as a consequence of tract anatomical variability. The present study highlights the importance of accounting for global sources of variation in DTI metrics when attempting to investigate individual differences (due to age, sex, or other factors) in specific white matter tracts.
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Affiliation(s)
- Stephanie Matijevic
- Cognition and Neuroimaging Laboratory, Department of Psychology, University of Arizona, Tucson, AZ, United States
| | - Lee Ryan
- Cognition and Neuroimaging Laboratory, Department of Psychology, University of Arizona, Tucson, AZ, United States
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Hagiwara A, Fujimoto K, Kamagata K, Murata S, Irie R, Kaga H, Someya Y, Andica C, Fujita S, Kato S, Fukunaga I, Wada A, Hori M, Tamura Y, Kawamori R, Watada H, Aoki S. Age-Related Changes in Relaxation Times, Proton Density, Myelin, and Tissue Volumes in Adult Brain Analyzed by 2-Dimensional Quantitative Synthetic Magnetic Resonance Imaging. Invest Radiol 2021; 56:163-172. [PMID: 32858581 PMCID: PMC7864648 DOI: 10.1097/rli.0000000000000720] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 07/20/2020] [Accepted: 07/20/2020] [Indexed: 11/04/2022]
Abstract
OBJECTIVES Quantitative synthetic magnetic resonance imaging (MRI) enables the determination of fundamental tissue properties, namely, T1 and T2 relaxation times and proton density (PD), in a single scan. Myelin estimation and brain segmentation based on these quantitative values can also be performed automatically. This study aimed to reveal the changes in tissue characteristics and volumes of the brain according to age and provide age-specific reference values obtained by quantitative synthetic MRI. MATERIALS AND METHODS This was a prospective study of healthy subjects with no history of brain diseases scanned with a multidynamic multiecho sequence for simultaneous measurement of relaxometry of T1, T2, and PD. We performed myelin estimation and brain volumetry based on these values. We performed volume-of-interest analysis on both gray matter (GM) and white matter (WM) regions for T1, T2, PD, and myelin volume fraction maps. Tissue volumes were calculated in the whole brain, producing brain parenchymal volume, GM volume, WM volume, and myelin volume. These volumes were normalized by intracranial volume to a brain parenchymal fraction, GM fraction, WM fraction, and myelin fraction (MyF). We examined the changes in the mean regional quantitative values and segmented tissue volumes according to age. RESULTS We analyzed data of 114 adults (53 men and 61 women; median age, 66.5 years; range, 21-86 years). T1, T2, and PD values showed quadratic changes according to age and stayed stable or decreased until around 60 years of age and increased thereafter. Myelin volume fraction showed a reversed trend. Brain parenchymal fraction and GM fraction decreased throughout all ages. The approximation curves showed that WM fraction and MyF gradually increased until around the 40s to 50s and decreased thereafter. A significant decline in MyF was first noted in the 60s age group (Tukey test, P < 0.001). CONCLUSIONS Our study showed changes according to age in tissue characteristic values and brain volumes using quantitative synthetic MRI. The reference values for age demonstrated in this study may be useful to discriminate brain disorders from healthy brains.
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Affiliation(s)
- Akifumi Hagiwara
- From the Department of Radiology, Juntendo University Graduate School of Medicine
| | - Kotaro Fujimoto
- From the Department of Radiology, Juntendo University Graduate School of Medicine
- Department of Radiology, Graduate School of Medicine, The University of Tokyo
| | - Koji Kamagata
- From the Department of Radiology, Juntendo University Graduate School of Medicine
| | - Syo Murata
- From the Department of Radiology, Juntendo University Graduate School of Medicine
| | - Ryusuke Irie
- From the Department of Radiology, Juntendo University Graduate School of Medicine
| | - Hideyoshi Kaga
- Department of Metabolism & Endocrinology, Juntendo University Graduate School of Medicine
| | - Yuki Someya
- Sportology Center, Juntendo University Graduate School of Medicine
| | - Christina Andica
- From the Department of Radiology, Juntendo University Graduate School of Medicine
| | - Shohei Fujita
- From the Department of Radiology, Juntendo University Graduate School of Medicine
- Department of Radiology, Graduate School of Medicine, The University of Tokyo
| | - Shimpei Kato
- From the Department of Radiology, Juntendo University Graduate School of Medicine
- Department of Radiology, Graduate School of Medicine, The University of Tokyo
| | - Issei Fukunaga
- Department of Radiological Technology, Faculty of Health Science, Juntendo University
| | - Akihiko Wada
- From the Department of Radiology, Juntendo University Graduate School of Medicine
| | - Masaaki Hori
- From the Department of Radiology, Juntendo University Graduate School of Medicine
- Department of Radiology, Toho University Omori Medical Center, Tokyo, Japan
| | - Yoshifumi Tamura
- Department of Metabolism & Endocrinology, Juntendo University Graduate School of Medicine
- Sportology Center, Juntendo University Graduate School of Medicine
| | - Ryuzo Kawamori
- Department of Metabolism & Endocrinology, Juntendo University Graduate School of Medicine
- Sportology Center, Juntendo University Graduate School of Medicine
| | - Hirotaka Watada
- Department of Metabolism & Endocrinology, Juntendo University Graduate School of Medicine
- Sportology Center, Juntendo University Graduate School of Medicine
| | - Shigeki Aoki
- From the Department of Radiology, Juntendo University Graduate School of Medicine
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45
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Astrogliosis and episodic memory in late life: higher GFAP is related to worse memory and white matter microstructure in healthy aging and Alzheimer's disease. Neurobiol Aging 2021; 103:68-77. [PMID: 33845398 DOI: 10.1016/j.neurobiolaging.2021.02.012] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 02/05/2021] [Accepted: 02/18/2021] [Indexed: 12/22/2022]
Abstract
Astrocytes play a formative role in memory consolidation during physiological conditions; when dysregulated, astrocytes release glial fibrillary acidic protein (GFAP), which has been linked with negative memory outcomes in animal studies. We examined the association between blood GFAP, memory, and white matter (WM) integrity, accounting for blood markers of AD pathology (i.e., Aβ42) and neurodegeneration (i.e., total tau; neurofilament light chain) in 114 older adults (asymptomatic, n = 69; MCI/AD dementia, n = 45). Higher levels of GFAP were associated with lower memory scores (p < 0.0001), such that for 1 SD increase in mean GFAP values, the memory composite score decreased on average by 0.49 (Standard error = 0.071). These results remained significant after controlling for diagnostic status and AD-related blood biomarkers. Higher GFAP was also related to lower WM integrity in regions vulnerable to AD pathology; however, WM integrity did not account for the association between GFAP and memory. Study findings suggest that higher blood levels of a marker of astrogliosis may reflect impoverished memory functions and white matter health, independent of markers of amyloid or neurodegeneration.
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46
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Coelho A, Fernandes HM, Magalhães R, Moreira PS, Marques P, Soares JM, Amorim L, Portugal-Nunes C, Castanho T, Santos NC, Sousa N. Signatures of white-matter microstructure degradation during aging and its association with cognitive status. Sci Rep 2021; 11:4517. [PMID: 33633204 PMCID: PMC7907273 DOI: 10.1038/s41598-021-83983-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 02/01/2021] [Indexed: 11/09/2022] Open
Abstract
Previous studies have shown an association between cognitive decline and white matter integrity in aging. This led to the formulation of a "disconnection hypothesis" in the aging-brain, which states that the disruption in cortical network communication may explain the cognitive decline during aging. Although some longitudinal studies have already investigated the changes occurring in white matter microstructure, most focused on specific white matter tracts. Our study aims to characterize the longitudinal whole-brain signatures of white matter microstructural change during aging. Furthermore, we assessed the relationship between distinct longitudinal alterations in white matter integrity and cognition. White matter microstructural properties were estimated from diffusion magnetic resonance imaging, and cognitive status characterized from extensive neurocognitive testing. The same individuals were evaluated at two timepoints, with a mean interval time of 52.8 months (SD = 7.24) between first and last assessment. Our results show that age is associated with a decline in cognitive performance and a degradation in white matter integrity. Additionally, significant associations were found between diffusion measures and different cognitive dimensions (memory, executive function and general cognition). Overall, these results suggest that age-related cognitive decline is related to white matter alterations, and thus give support to the "disconnected hypothesis" of the aging brain.
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Affiliation(s)
- Ana Coelho
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057, Braga, Portugal
- ICVS/3B's, PT Government Associate Laboratory, 4710-057, Braga/Guimarães, Portugal
- Clinical Academic Center-Braga, 4710-057, Braga, Portugal
| | - Henrique M Fernandes
- Center for Music in the Brain (MIB), Aarhus University, Aarhus, Denmark
- Department of Psychiatry, University of Oxford, Oxford, UK
| | - Ricardo Magalhães
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057, Braga, Portugal
- ICVS/3B's, PT Government Associate Laboratory, 4710-057, Braga/Guimarães, Portugal
- Clinical Academic Center-Braga, 4710-057, Braga, Portugal
| | - Pedro Silva Moreira
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057, Braga, Portugal
- ICVS/3B's, PT Government Associate Laboratory, 4710-057, Braga/Guimarães, Portugal
- Clinical Academic Center-Braga, 4710-057, Braga, Portugal
| | - Paulo Marques
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057, Braga, Portugal
- ICVS/3B's, PT Government Associate Laboratory, 4710-057, Braga/Guimarães, Portugal
- Clinical Academic Center-Braga, 4710-057, Braga, Portugal
| | - José M Soares
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057, Braga, Portugal
- ICVS/3B's, PT Government Associate Laboratory, 4710-057, Braga/Guimarães, Portugal
- Clinical Academic Center-Braga, 4710-057, Braga, Portugal
| | - Liliana Amorim
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057, Braga, Portugal
- ICVS/3B's, PT Government Associate Laboratory, 4710-057, Braga/Guimarães, Portugal
- Clinical Academic Center-Braga, 4710-057, Braga, Portugal
| | - Carlos Portugal-Nunes
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057, Braga, Portugal
- ICVS/3B's, PT Government Associate Laboratory, 4710-057, Braga/Guimarães, Portugal
- Clinical Academic Center-Braga, 4710-057, Braga, Portugal
| | - Teresa Castanho
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057, Braga, Portugal
- ICVS/3B's, PT Government Associate Laboratory, 4710-057, Braga/Guimarães, Portugal
- Clinical Academic Center-Braga, 4710-057, Braga, Portugal
| | - Nadine Correia Santos
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057, Braga, Portugal
- ICVS/3B's, PT Government Associate Laboratory, 4710-057, Braga/Guimarães, Portugal
- Clinical Academic Center-Braga, 4710-057, Braga, Portugal
| | - Nuno Sousa
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057, Braga, Portugal.
- ICVS/3B's, PT Government Associate Laboratory, 4710-057, Braga/Guimarães, Portugal.
- Clinical Academic Center-Braga, 4710-057, Braga, Portugal.
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47
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Bouhrara M, Kim RW, Khattar N, Qian W, Bergeron CM, Melvin D, Zukley LM, Ferrucci L, Resnick SM, Spencer RG. Age-related estimates of aggregate g-ratio of white matter structures assessed using quantitative magnetic resonance neuroimaging. Hum Brain Mapp 2021; 42:2362-2373. [PMID: 33595168 PMCID: PMC8090765 DOI: 10.1002/hbm.25372] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 01/21/2021] [Accepted: 02/04/2021] [Indexed: 12/19/2022] Open
Abstract
The g‐ratio, defined as the inner‐to‐outer diameter of a myelinated axon, is associated with the speed of nerve impulse conduction, and represents an index of axonal myelination and integrity. It has been shown to be a sensitive and specific biomarker of neurodevelopment and neurodegeneration. However, there have been very few magnetic resonance imaging studies of the g‐ratio in the context of normative aging; characterizing regional and time‐dependent cerebral changes in g‐ratio in cognitively normal subjects will be a crucial step in differentiating normal from abnormal microstructural alterations. In the current study, we investigated age‐related differences in aggregate g‐ratio, that is, g‐ratio averaged over all fibers within regions of interest, in several white matter regions in a cohort of 52 cognitively unimpaired participants ranging in age from 21 to 84 years. We found a quadratic, U‐shaped, relationship between aggregate g‐ratio and age in most cerebral regions investigated, suggesting myelin maturation until middle age followed by a decrease at older ages. As expected, we observed that these age‐related differences vary across different brain regions, with the frontal lobes and parietal lobes exhibiting slightly earlier ages of minimum aggregate g‐ratio as compared to more posterior structures such as the occipital lobes and temporal lobes; this agrees with the retrogenesis paradigm. Our results provide evidence for a nonlinear association between age and aggregate g‐ratio in a sample of adults from a highly controlled population. Finally, sex differences in aggregate g‐ratio were observed in several cerebral regions, with women exhibiting overall lower values as compared to men; this likely reflects the greater myelin content in women's brain, in agreement with recent investigations.
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Affiliation(s)
- Mustapha Bouhrara
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Richard W Kim
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Nikkita Khattar
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Wenshu Qian
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Christopher M Bergeron
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Denise Melvin
- Clinical Research Core, Office of the Scientific Director, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Linda M Zukley
- Clinical Research Core, Office of the Scientific Director, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Luigi Ferrucci
- Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Susan M Resnick
- Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Richard G Spencer
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
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48
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Umapathy L, Perez-Carrillo GG, Keerthivasan MB, Rosado-Toro JA, Altbach MI, Winegar B, Weinkauf C, Bilgin A. A Stacked Generalization of 3D Orthogonal Deep Learning Convolutional Neural Networks for Improved Detection of White Matter Hyperintensities in 3D FLAIR Images. AJNR Am J Neuroradiol 2021; 42:639-647. [PMID: 33574101 DOI: 10.3174/ajnr.a6970] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 10/26/2020] [Indexed: 01/18/2023]
Abstract
BACKGROUND AND PURPOSE Accurate and reliable detection of white matter hyperintensities and their volume quantification can provide valuable clinical information to assess neurologic disease progression. In this work, a stacked generalization ensemble of orthogonal 3D convolutional neural networks, StackGen-Net, is explored for improving automated detection of white matter hyperintensities in 3D T2-FLAIR images. MATERIALS AND METHODS Individual convolutional neural networks in StackGen-Net were trained on 2.5D patches from orthogonal reformatting of 3D-FLAIR (n = 21) to yield white matter hyperintensity posteriors. A meta convolutional neural network was trained to learn the functional mapping from orthogonal white matter hyperintensity posteriors to the final white matter hyperintensity prediction. The impact of training data and architecture choices on white matter hyperintensity segmentation performance was systematically evaluated on a test cohort (n = 9). The segmentation performance of StackGen-Net was compared with state-of-the-art convolutional neural network techniques on an independent test cohort from the Alzheimer's Disease Neuroimaging Initiative-3 (n = 20). RESULTS StackGen-Net outperformed individual convolutional neural networks in the ensemble and their combination using averaging or majority voting. In a comparison with state-of-the-art white matter hyperintensity segmentation techniques, StackGen-Net achieved a significantly higher Dice score (0.76 [SD, 0.08], F1-lesion (0.74 [SD, 0.13]), and area under precision-recall curve (0.84 [SD, 0.09]), and the lowest absolute volume difference (13.3% [SD, 9.1%]). StackGen-Net performance in Dice scores (median = 0.74) did not significantly differ (P = .22) from interobserver (median = 0.73) variability between 2 experienced neuroradiologists. We found no significant difference (P = .15) in white matter hyperintensity lesion volumes from StackGen-Net predictions and ground truth annotations. CONCLUSIONS A stacked generalization of convolutional neural networks, utilizing multiplanar lesion information using 2.5D spatial context, greatly improved the segmentation performance of StackGen-Net compared with traditional ensemble techniques and some state-of-the-art deep learning models for 3D-FLAIR.
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Affiliation(s)
- L Umapathy
- From the Departments of Electrical and Computer Engineering (L.U., A.B.).,Medical Imaging (L.U., G.G.P.-C., M.B.K., J.A.R.-T., M.I.A., B.W., A.B.)
| | - G G Perez-Carrillo
- Medical Imaging (L.U., G.G.P.-C., M.B.K., J.A.R.-T., M.I.A., B.W., A.B.)
| | - M B Keerthivasan
- Medical Imaging (L.U., G.G.P.-C., M.B.K., J.A.R.-T., M.I.A., B.W., A.B.)
| | - J A Rosado-Toro
- Medical Imaging (L.U., G.G.P.-C., M.B.K., J.A.R.-T., M.I.A., B.W., A.B.)
| | - M I Altbach
- Medical Imaging (L.U., G.G.P.-C., M.B.K., J.A.R.-T., M.I.A., B.W., A.B.)
| | - B Winegar
- Medical Imaging (L.U., G.G.P.-C., M.B.K., J.A.R.-T., M.I.A., B.W., A.B.)
| | | | - A Bilgin
- From the Departments of Electrical and Computer Engineering (L.U., A.B.) .,Medical Imaging (L.U., G.G.P.-C., M.B.K., J.A.R.-T., M.I.A., B.W., A.B.).,Biomedical Engineering (A.B.), University of Arizona, Tucson, Arizona
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49
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Poulakis K, Reid RI, Przybelski SA, Knopman DS, Graff-Radford J, Lowe VJ, Mielke MM, Machulda MM, Jack CR, Petersen RC, Westman E, Vemuri P. Longitudinal deterioration of white-matter integrity: heterogeneity in the ageing population. Brain Commun 2021; 3:fcaa238. [PMID: 33615218 PMCID: PMC7884606 DOI: 10.1093/braincomms/fcaa238] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 11/18/2020] [Accepted: 11/19/2020] [Indexed: 02/07/2023] Open
Abstract
Deterioration in white-matter health plays a role in cognitive ageing. Our goal was to discern heterogeneity of white-matter tract vulnerability in ageing using longitudinal imaging data (two to five imaging and cognitive assessments per participant) from a population-based sample of 553 elderly participants (age ≥60 years). We found that different clusters (healthy white matter, fast white-matter decliners and intermediate white-matter group) were heterogeneous in the spatial distribution of white-matter integrity, systemic health and cognitive trajectories. White-matter health of specific tracts (genu of corpus callosum, posterior corona radiata and anterior internal capsule) informed about cluster assignments. Not surprisingly, brain amyloidosis was not significantly different between clusters. Clusters had differential white-matter tract vulnerability to ageing (commissural fibres > association/brainstem fibres). Identification of vulnerable white-matter tracts is a valuable approach to assessing risk for cognitive decline.
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Affiliation(s)
- Konstantinos Poulakis
- Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm 141 52, Sweden
| | - Robert I Reid
- Department of Radiology, Mayo Clinic, Rochester, MN 559 05, USA
| | | | - David S Knopman
- Department of Radiology, Mayo Clinic, Rochester, MN 559 05, USA
| | | | - Val J Lowe
- Department of Radiology, Mayo Clinic, Rochester, MN 559 05, USA
| | | | - Mary M Machulda
- Department of Radiology, Mayo Clinic, Rochester, MN 559 05, USA
| | - Clifford R Jack
- Department of Radiology, Mayo Clinic, Rochester, MN 559 05, USA
| | | | - Eric Westman
- Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm 141 52, Sweden
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50
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Frontoparietal microstructural damage mediates age-dependent working memory decline in face and body information processing: Evidence for dichotomic hemispheric bias mechanisms. Neuropsychologia 2020; 151:107726. [PMID: 33321120 DOI: 10.1016/j.neuropsychologia.2020.107726] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 11/28/2020] [Accepted: 12/09/2020] [Indexed: 11/24/2022]
Abstract
Age-associated damage in the microstructure of frontally-based connections (e.g. genu of the corpus callosum and superior longitudinal fasciculus) is believed to lead to impairments in processing speed and executive function. Using mediation analysis, we tested the potential contribution of callosal and frontoparietal association tracts to age-dependent effects on cognition/executive function as measured with 1-back working memory tasks for visual stimulus categories (i.e. faces and non-emotional bodies) in a group of 55 healthy adults (age range 23-79 years). Constrained spherical deconvolution-based tractography was employed to reconstruct the genu/prefrontal section of the corpus callosum (GCC) and the central/second branch of the superior longitudinal fasciculus (CB-SLF). Age was associated with (i) reductions in fractional anisotropy (FA) in the GCC and in the right and left CB-SLF and (iii) decline in visual object category processing. Mediation analysis revealed that microstructural damage in right hemispheric CB-SLF is associated with age-dependent decline in face processing likely reflecting the stimulus-specific/holistic nature of face processing within dedicated/specialized frontoparietal routes. By contrast, microstructural damage in left hemispheric CB-SLF associated with age-dependent decline in non-emotional body processing, consistent with the more abstract nature of non-emotional body categories. In sum, our findings suggest that frontoparietal microstructural damage mediates age-dependent decline in face and body information processing in a manner that reflects the hemispheric bias of holistic vs. abstract nature of face and non-emotional body category processing.
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