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Nunley KA, Leckie RL, Orchard TJ, Costacou T, Aizenstein HJ, Jennings JR, Erickson KI, Rosano C. Physical activity and hippocampal volume in middle-aged patients with type 1 diabetes. Neurology 2017; 88:1564-1570. [PMID: 28283592 DOI: 10.1212/wnl.0000000000003805] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 01/24/2017] [Indexed: 12/25/2022] Open
Abstract
OBJECTIVE To examine the cross-sectional association between physical activity (PA) and hippocampal volume in middle-aged adults with childhood-onset type 1 diabetes (T1D), and whether hyperglycemia and insulin sensitivity contribute to this relationship. METHODS We analyzed neuroimaging and self-reported PA data from 79 adults with T1D from the Pittsburgh Epidemiology of Diabetes Complications Study (mean age 50 years, mean duration 41 years) and 122 similarly aged adults without T1D (mean age 48 years). Linear regression models, controlling for intracranial volume, sex, education, and age, tested associations between PA and gray matter volumes of hippocampi and total brain in the 2 groups. For the T1D group, models further controlled for hyperglycemia and glucose disposal rate, a measure of insulin sensitivity. RESULTS PA was significantly lower in the T1D than in the non-T1D group (median [interquartile range] 952 kcal [420-2,044] vs 1,614 kcal [588-3,091], respectively). Higher PA was significantly associated with larger hippocampi for T1D, but not for non-T1D (standardized β [p values] from regression models adjusted for intracranial volume, sex, age, and education: 0.270 [p < 0.001] and 0.098 [p = 0.12], respectively). Neither hyperglycemia nor glucose disposal rate substantially modified this association. Relationships between PA and total brain gray matter volume were similar. CONCLUSIONS A cross-sectional association between higher PA and larger hippocampi is already detectable by middle age for these patients with T1D, and it appears robust to chronic hyperglycemia and insulin sensitivity. Proof-of-concept studies should investigate whether increasing PA preserves hippocampal volume and the mechanisms underlying the effects of PA on hippocampal volume.
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Affiliation(s)
- Karen A Nunley
- From the Department of Epidemiology, Graduate School of Public Health (K.A.N., T.J.O., T.C., C.R.), Department of Psychology (R.L.L., J.R.J., K.I.E.), and Department of Psychiatry, School of Medicine (H.J.A., J.R.J.), University of Pittsburgh, PA.
| | - Regina L Leckie
- From the Department of Epidemiology, Graduate School of Public Health (K.A.N., T.J.O., T.C., C.R.), Department of Psychology (R.L.L., J.R.J., K.I.E.), and Department of Psychiatry, School of Medicine (H.J.A., J.R.J.), University of Pittsburgh, PA
| | - Trevor J Orchard
- From the Department of Epidemiology, Graduate School of Public Health (K.A.N., T.J.O., T.C., C.R.), Department of Psychology (R.L.L., J.R.J., K.I.E.), and Department of Psychiatry, School of Medicine (H.J.A., J.R.J.), University of Pittsburgh, PA
| | - Tina Costacou
- From the Department of Epidemiology, Graduate School of Public Health (K.A.N., T.J.O., T.C., C.R.), Department of Psychology (R.L.L., J.R.J., K.I.E.), and Department of Psychiatry, School of Medicine (H.J.A., J.R.J.), University of Pittsburgh, PA
| | - Howard J Aizenstein
- From the Department of Epidemiology, Graduate School of Public Health (K.A.N., T.J.O., T.C., C.R.), Department of Psychology (R.L.L., J.R.J., K.I.E.), and Department of Psychiatry, School of Medicine (H.J.A., J.R.J.), University of Pittsburgh, PA
| | - J Richard Jennings
- From the Department of Epidemiology, Graduate School of Public Health (K.A.N., T.J.O., T.C., C.R.), Department of Psychology (R.L.L., J.R.J., K.I.E.), and Department of Psychiatry, School of Medicine (H.J.A., J.R.J.), University of Pittsburgh, PA
| | - Kirk I Erickson
- From the Department of Epidemiology, Graduate School of Public Health (K.A.N., T.J.O., T.C., C.R.), Department of Psychology (R.L.L., J.R.J., K.I.E.), and Department of Psychiatry, School of Medicine (H.J.A., J.R.J.), University of Pittsburgh, PA
| | - Caterina Rosano
- From the Department of Epidemiology, Graduate School of Public Health (K.A.N., T.J.O., T.C., C.R.), Department of Psychology (R.L.L., J.R.J., K.I.E.), and Department of Psychiatry, School of Medicine (H.J.A., J.R.J.), University of Pittsburgh, PA
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Vigneshwari GM, Ramamoorthy S, Muralikrishnan A, Srivastava P, Pathania M, Krishnaswamy S. MPDB: Molecular Pathways Brain Database. Bioinformation 2016; 12:32-35. [PMID: 28104956 PMCID: PMC5237643 DOI: 10.6026/97320630012032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2016] [Revised: 02/25/2016] [Accepted: 02/26/2016] [Indexed: 11/23/2022] Open
Abstract
Molecular Pathways Brain Database (MPDB), is a novel database for molecular information of the brain pathways and is an initiative to provide an organized platform for researchers in the field of neuro-informatics. The database currently has information from 1850 molecules for three different sensory pathways namely olfactory transduction, photo transduction and long-term potentiation. The usefulness of the database is demonstrated by an analysis of the olfactory transduction pathway which helps understand their olfactory specifity and further indicates that some of the molecules have evolved independently among these organisms as per the need of time and function. The database is available for free at http://pranag.physics.iisc.ernet.in/mpdb/.
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Affiliation(s)
- Gopal Madhana Vigneshwari
- Centre of Excellence in Bioinformatics, School of Biotechnology, Madurai Kamaraj University, Madurai - 625021
| | - Sankaranarayana Ramamoorthy
- Centre of Excellence in Bioinformatics, School of Biotechnology, Madurai Kamaraj University, Madurai - 625021
| | - Aarathy Muralikrishnan
- Centre of Excellence in Bioinformatics, School of Biotechnology, Madurai Kamaraj University, Madurai - 625021
| | - Prerna Srivastava
- Centre of Excellence in Bioinformatics, School of Biotechnology, Madurai Kamaraj University, Madurai - 625021
| | - Monisha Pathania
- Centre of Excellence in Bioinformatics, School of Biotechnology, Madurai Kamaraj University, Madurai - 625021
| | - Sankaran Krishnaswamy
- Centre of Excellence in Bioinformatics, School of Biotechnology, Madurai Kamaraj University, Madurai - 625021
- Institute of Mathematical Sciences, Chennai - 600113, India
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Khalaf A, Edelman K, Tudorascu D, Andreescu C, Reynolds CF, Aizenstein H. White Matter Hyperintensity Accumulation During Treatment of Late-Life Depression. Neuropsychopharmacology 2015; 40:3027-35. [PMID: 26058663 PMCID: PMC4864637 DOI: 10.1038/npp.2015.158] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 05/26/2015] [Accepted: 05/30/2015] [Indexed: 12/19/2022]
Abstract
White matter hyperintensities (WMHs) have been shown to be associated with the development of late-life depression (LLD) and eventual treatment outcomes. This study sought to investigate longitudinal WMH changes in patients with LLD during a 12-week antidepressant treatment course. Forty-seven depressed elderly patients were included in this analysis. All depressed subjects started pharmacological treatment for depression shortly after a baseline magnetic resonance imaging (MRI) scan. At 12 weeks, patients underwent a follow-up MRI scan, and were categorized as either treatment remitters (n=23) or non-remitters (n=24). Among all patients, there was as a significant increase in WMHs over 12 weeks (t(46)=2.36, P=0.02). When patients were stratified by remission status, non-remitters demonstrated a significant increase in WMHs (t(23)=2.17, P=0.04), but this was not observed in remitters (t(22)=1.09, P=0.29). Other markers of brain integrity were also investigated including whole brain gray matter volume, hippocampal volume, and fractional anisotropy. No significant differences were observed in any of these markers during treatment, including when patients were stratified based on remission status. These results add to existing literature showing the association between WMH accumulation and LLD treatment outcomes. Moreover, this is the first study to demonstrate similar findings over a short interval (ie 12 weeks), which corresponds to the typical length of an antidepressant trial. These findings serve to highlight the acute interplay of cerebrovascular ischemic disease and LLD.
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Affiliation(s)
- Alexander Khalaf
- Western Psychiatric Institute and Clinic, Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA
| | - Kathryn Edelman
- Western Psychiatric Institute and Clinic, Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA
| | - Dana Tudorascu
- Western Psychiatric Institute and Clinic, Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA
| | - Carmen Andreescu
- Western Psychiatric Institute and Clinic, Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA
| | - Charles F Reynolds
- Western Psychiatric Institute and Clinic, Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA
| | - Howard Aizenstein
- Western Psychiatric Institute and Clinic, Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA,Western Psychiatric Institute and Clinic, University of Pittsburgh, 3811 O'Hara Street, Room 459, Pittsburgh, PA 15213, USA, Tel: +1 412 246 5464, Fax: + 1 412 586 9111, E-mail:
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Olson Hunt MJ, Weissfeld L, Boudreau RM, Aizenstein H, Newman AB, Simonsick EM, Van Domelen DR, Thomas F, Yaffe K, Rosano C. A variant of sparse partial least squares for variable selection and data exploration. Front Neuroinform 2014; 8:18. [PMID: 24624079 PMCID: PMC3939647 DOI: 10.3389/fninf.2014.00018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 02/11/2014] [Indexed: 11/15/2022] Open
Abstract
When data are sparse and/or predictors multicollinear, current implementation of sparse partial least squares (SPLS) does not give estimates for non-selected predictors nor provide a measure of inference. In response, an approach termed “all-possible” SPLS is proposed, which fits a SPLS model for all tuning parameter values across a set grid. Noted is the percentage of time a given predictor is chosen, as well as the average non-zero parameter estimate. Using a “large” number of multicollinear predictors, simulation confirmed variables not associated with the outcome were least likely to be chosen as sparsity increased across the grid of tuning parameters, while the opposite was true for those strongly associated. Lastly, variables with a weak association were chosen more often than those with no association, but less often than those with a strong relationship to the outcome. Similarly, predictors most strongly related to the outcome had the largest average parameter estimate magnitude, followed by those with a weak relationship, followed by those with no relationship. Across two independent studies regarding the relationship between volumetric MRI measures and a cognitive test score, this method confirmed a priori hypotheses about which brain regions would be selected most often and have the largest average parameter estimates. In conclusion, the percentage of time a predictor is chosen is a useful measure for ordering the strength of the relationship between the independent and dependent variables, serving as a form of inference. The average parameter estimates give further insight regarding the direction and strength of association. As a result, all-possible SPLS gives more information than the dichotomous output of traditional SPLS, making it useful when undertaking data exploration and hypothesis generation for a large number of potential predictors.
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Affiliation(s)
- Megan J Olson Hunt
- Department of Biostatistics, University of Pittsburgh Pittsburgh, PA, USA
| | - Lisa Weissfeld
- Department of Biostatistics, University of Pittsburgh Pittsburgh, PA, USA
| | - Robert M Boudreau
- Department of Epidemiology, Center for Aging and Population Health, University of Pittsburgh Pittsburgh, PA, USA
| | - Howard Aizenstein
- Departments of Psychiatry, Bioengineering and Clinical and Translational Science, University of Pittsburgh Pittsburgh, PA, USA
| | - Anne B Newman
- Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh Pittsburgh, PA, USA
| | | | | | - Fridtjof Thomas
- Department of Preventive Medicine, University of Tennessee Health Science Center Memphis, TN, USA
| | - Kristine Yaffe
- Department of Psychiatry, Neurology and Epidemiology, University of California, San Francisco San Francisco, CA, USA
| | - Caterina Rosano
- Department of Epidemiology, Center for Aging and Population Health, University of Pittsburgh Pittsburgh, PA, USA
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Abstract
There are well-established patterns of structural brain changes associated with aging. The change in brain volume with age and with the diseases of aging presents a particular challenge for MRI studies in the elderly. Structural MRI is important for studies in normal aging, late-life depression, dementia, Alzheimer disease and other cognitive disorders to examine how age-associated changes in neuroanatomy are associated with specific age-related changes in brain function. Functional MRI has been a major advance for the fields of cognitive and affective neuroscience by allowing investigators to test theories of the underlying neural pathways controlling cognitive and emotional processes. In this chapter, we will review the contribution of MRI studies to late-life mood and anxiety disorders: major depression, bipolar disorder and anxiety disorders in late-life.
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Rosano C, Studenski SA, Aizenstein HJ, Boudreau RM, Longstreth WT, Newman AB. Slower gait, slower information processing and smaller prefrontal area in older adults. Age Ageing 2012; 41:58-64. [PMID: 21965414 DOI: 10.1093/ageing/afr113] [Citation(s) in RCA: 153] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Slower gait in older adults is related to smaller volume of the prefrontal area (PFAv). The pathways underlying this association have not yet been explored. Understanding slowing gait could help improve function in older age. We examine whether the association between smaller PFAv and slower gait is explained by lower performance on numerous neuropsychological tests. HYPOTHESIS We hypothesise that slower information processing explains this association, while tests of language or memory will not. METHODS Data on brain imaging, neuropsychological tests (information processing speed, visuospatial attention, memory, language, mood) and time to walk 15 feet were obtained in 214 adults (73.3 years, 62% women) free from stroke and dementia. Covariates included central (white matter hyperintensities, vision) and peripheral contributors of gait (vibration sense, muscle strength, arthritis, body mass index), demographics (age, race, gender, education), as well as markers of prevalent vascular diseases (cardiovascular disease, diabetes and ankle arm index). RESULTS In linear regression models, smaller PFAv was associated with slower time to walk independent of covariates. This association was no longer significant after adding information processing speed to the model. None of the other neuropsychological tests significantly attenuated this association. CONCLUSIONS We conclude that smaller PFAv may contribute to slower gait through slower information processing. Future longitudinal studies are warranted to examine the casual relationship between focal brain atrophy with slowing in information processing and gait.
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Affiliation(s)
- Caterina Rosano
- Department of Epidemiology, Graduate School of Public Health, 130 N. Bellefield Avenue, Pittsburgh, PA 15213, USA.
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Rosano C, Venkatraman VK, Guralnik J, Newman AB, Glynn NW, Launer L, Taylor CA, Williamson J, Studenski S, Pahor M, Aizenstein H. Psychomotor speed and functional brain MRI 2 years after completing a physical activity treatment. J Gerontol A Biol Sci Med Sci 2010; 65:639-47. [PMID: 20348185 DOI: 10.1093/gerona/glq038] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Short-term adherence to physical activity (PA) in older adults improves psychomotor processing abilities and is associated with greater brain activation. It is not known whether these associations are also significant for longer-term adherence to moderate-intensity activities. METHODS We measured the cross-sectional association of regular walking with brain activation while performing the digit symbol substitution test (DSST). Participants of the lifestyle interventions and independence for elders-pilot study were examined 2 years after completing a 1-year treatment, consisting of either PA or education in successful aging (SA). Data were obtained from 20 PA participants who reported having remained active for 2 years after the end of the treatment and from 10 SA participants who reported having remained sedentary during the same period (mean age: 81.5 and 80.8 years). Complete brain activation and behavioral data were available for 17 PA and 10 SA participants. RESULTS Two years after the formal intervention had ended, the PA group engaged in more minutes of moderate activity and had significantly greater DSST score and higher brain activation within regions important for processing speed (left dorsolateral prefrontal, posterior parietal, and anterior cingulate cortices). Associations were independent of self-reported health, blood pressure, cognition, medication records, gray matter atrophy, and white matter hyperintensities. CONCLUSIONS Persistent engagement in PA may have beneficial effects on psychomotor processing speed and brain activation, even for moderate levels and even when started late in life. Future studies are warranted to assess whether these beneficial effects are explained by delayed neuronal degeneration and/or new neurogenesis.
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Affiliation(s)
- Caterina Rosano
- Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, 130 North Bellefield Street, Room 512, Pittsburgh, PA 15213, USA.
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Venkatraman VK, Aizenstein H, Guralnik J, Newman AB, Glynn NW, Taylor C, Studenski S, Launer L, Pahor M, Williamson J, Rosano C. Executive control function, brain activation and white matter hyperintensities in older adults. Neuroimage 2009; 49:3436-42. [PMID: 19922803 DOI: 10.1016/j.neuroimage.2009.11.019] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2009] [Revised: 11/06/2009] [Accepted: 11/10/2009] [Indexed: 10/20/2022] Open
Abstract
CONTEXT Older adults responding to executive control function (ECF) tasks show greater brain activation on functional MRI (fMRI). It is not clear whether greater fMRI activation indicates a strategy to compensate for underlying brain structural abnormalities while maintaining higher performance. OBJECTIVE To identify the patterns of fMRI activation in relationship with ECF performance and with brain structural abnormalities. DESIGN Cross-sectional analysis. MAIN VARIABLES OF INTEREST fMRI activation, accuracy while performing an ECF task (Digit Symbol Substitution Test), and volume of white matter hyperintensities and of total brain atrophy. SETTING Cohort of community-dwelling older adults. PARTICIPANTS Data were obtained on 25 older adults (20 women, 81 years mean age). OUTCOME MEASURE Accuracy (number of correct response/total number of responses) while performing the Digit Symbol Substitution Test. RESULTS Greater accuracy was significantly associated with greater peak fMRI activation, from ECF regions, including left middle frontal gyrus and right posterior parietal cortex. Greater WMH was associated with lower activation within accuracy-related regions. The interaction of accuracy by white matter hyperintensity volume was significant within the left posterior parietal region. Specifically, the correlation of white matter hyperintensity volume with fMRI activation varied as a function of accuracy and it was positive for greater accuracy. Associations with brain atrophy were not significant. CONCLUSIONS Recruitment of additional areas and overall greater brain activation in older adults is associated with higher performance. Posterior parietal activation may be particularly important to maintain higher accuracy in the presence of underlying brain connectivity structural abnormalities.
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Affiliation(s)
- Vijay K Venkatraman
- Department of Bioengineering, School of Engineering, University of Pittsburgh, Pittsburgh, PA 15261, USA
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Abstract
OBJECTIVE To test whether current gray matter volume (GMV) covaried with previously obtained longitudinal measures of weight gain-as assessed by increases in body mass index (BMI)-among otherwise healthy postmenopausal women. Cross-sectional results indicate that reduced GMV may be associated with excess body weight. METHODS Demographic, biometric, and behavioral measures were obtained from 48 women as part of the Pittsburgh Healthy Women Study, a longitudinal epidemiological investigation initiated between 1983 and 1984. In 2005 and 2006, these women took part in a brain imaging protocol. RESULTS Premenopausal BMI and a priori chosen confounding variables, including the number of years post menopause, an aggregate measure of perceived life stress spanning a 20-year period, resting blood pressure, total cerebral volume, and severity of white matter hyperintensities (a suspected indicator of aging-related silent cerebrovascular disease), explained approximately 22% of variance in total GMV. An additional 15% of the variance was uniquely explained by the change in BMI between pre- and postmenopausal longitudinal assessments, such that an increase in BMI predicted a greater reduction in GMV. CONCLUSIONS An increase in BMI during the menopausal transition and beyond is associated with reduced GMV among otherwise healthy women.
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Rosano C, Aizenstein H, Brach J, Longenberger A, Studenski S, Newman AB. Special article: gait measures indicate underlying focal gray matter atrophy in the brain of older adults. J Gerontol A Biol Sci Med Sci 2009; 63:1380-8. [PMID: 19126852 DOI: 10.1093/gerona/63.12.1380] [Citation(s) in RCA: 161] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVE Our objective was to identify the spatial distribution of focal atrophy within mobility-related brain regions in relationship with quantitative gait characteristics. METHODS Gray matter volume was obtained from 220 older adults (78.0 years old, 63% women, 77% white) for brain regions of five domains: motor (motor, sensorimotor and supplementary areas, basal ganglia, cerebellum), visuospatial attention (inferior and superior posterior parietal lobules), cognitive processing speed/executive control function (dorsolateral prefrontal cortex), memory (hippocampus), and motor imagery (parahippocampus, posterior cingulated cortex) domains. Spatial (step width, step length) and temporal (double support time) gait characteristics were measured using the GaitMat II instrumented walking surface. Multivariable linear regression models were adjusted for demographics, total brain volume, and peripheral (body mass index, ankle-arm index, arthritis, vibratory sensation) and central (markers of diffuse brain structural abnormalities and of brain function) risk factors for gait impairment. RESULTS Shorter steps and longer double support times were associated with smaller sensorimotor regions and also with smaller frontoparietal regions within the motor, visuospatial, and cognitive processing speed domains. The associations between wider step and smaller pallidum and inferior parietal lobule were less robust. None of the gait measures were associated with the cerebellum or with regions of the memory or motor imagery domains. CONCLUSIONS Spatial and temporal characteristics of gait are associated with distinct brain networks in older adults. Addressing focal neuronal losses in these networks may represent an important strategy to prevent mobility disability.
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Affiliation(s)
- Caterina Rosano
- Department of Epidemiology, University of Pittsburgh, Pittsburgh, PA, USA.
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Andreescu C, Butters MA, Begley A, Rajji T, Wu M, Meltzer CC, Reynolds CF, Aizenstein H. Gray matter changes in late life depression--a structural MRI analysis. Neuropsychopharmacology 2008; 33:2566-72. [PMID: 18075490 PMCID: PMC2872084 DOI: 10.1038/sj.npp.1301655] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Multiple brain morphometric changes have been reported in late-life depression (LLD), mostly in studies comparing volumes of circumscribed brain areas. The aim of our study is to characterize the volumetric changes of multiple gray matter regions in relation to age of onset/duration of illness. We predicted that the association of gray matter volumes with total duration of illness and age of onset would differ depending on whether the region was susceptible to the toxic effects of chronic exposure to cortisol or to the vascular/neurodegenerative changes accompanying prodromal dementia. Seventy-one elderly depressed subjects were studied along with thirty-two comparison subjects. High-resolution T1-weighted brain MRIs were processed using an automated labeling pathway technique. To protect against type-I error, we combined the right and left hemisphere volume data. We sampled 24 regions of interest (ROIs). We used the primary visual cortex volume to normalize for individual variations in brain size. LLD Subjects had smaller volumes than non-depressed subjects in 17 of the 24 examined ROIs. Shorter duration of illness and later age of onset was correlated with smaller volumes of parahippocampal area and parietal inferior area. A later age of onset was also correlated with smaller volumes of several frontal and temporal areas, cingulum, and putamen. Our findings support a dementia prodrome model more strongly than a toxic stress model in this group of subjects. However, it remains likely that both processes as well as other factors contribute to the heterogeneity of volumetric brain changes in LLD.
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Affiliation(s)
- Carmen Andreescu
- The Advanced Center for Interventions and Services Research for Late-life Mood Disorders, Department of Psychiatry, University of Pittsburgh School of Medicine and the John A Hartford Center of Excellence in Geriatric Psychiatry, Pittsburgh, PA, USA
| | - Meryl A Butters
- The Advanced Center for Interventions and Services Research for Late-life Mood Disorders, Department of Psychiatry, University of Pittsburgh School of Medicine and the John A Hartford Center of Excellence in Geriatric Psychiatry, Pittsburgh, PA, USA
| | - Amy Begley
- The Advanced Center for Interventions and Services Research for Late-life Mood Disorders, Department of Psychiatry, University of Pittsburgh School of Medicine and the John A Hartford Center of Excellence in Geriatric Psychiatry, Pittsburgh, PA, USA
| | - Tarek Rajji
- Centre for Addiction and Mental Health, University of Toronto, Toronto, ON, Canada
| | - Minjie Wu
- Department of Electrical and Computer Engineering, University of Pittsburgh, Pittsburgh, PA, USA
| | - Carolyn C Meltzer
- The Advanced Center for Interventions and Services Research for Late-life Mood Disorders, Department of Psychiatry, University of Pittsburgh School of Medicine and the John A Hartford Center of Excellence in Geriatric Psychiatry, Pittsburgh, PA, USA,Department of Neurology, University of Pittsburgh, Pittsburgh, PA, USA,Departments of Radiology, Neurology, Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - Charles F Reynolds
- The Advanced Center for Interventions and Services Research for Late-life Mood Disorders, Department of Psychiatry, University of Pittsburgh School of Medicine and the John A Hartford Center of Excellence in Geriatric Psychiatry, Pittsburgh, PA, USA
| | - Howard Aizenstein
- The Advanced Center for Interventions and Services Research for Late-life Mood Disorders, Department of Psychiatry, University of Pittsburgh School of Medicine and the John A Hartford Center of Excellence in Geriatric Psychiatry, Pittsburgh, PA, USA,Department of Bioengineering , University of Pittsburgh, Pittsburgh, PA, USA,Correspondence: Dr H Aizenstein, Department of Psychiatry and Bioengineering, Western Psychiatric Institute and Clinic, University of Pittsburgh, 3811 O’Hara Street, Pittsburgh, PA 15213, USA, Tel: + 1 412 383 5452, Fax: + 1 412 383 5458, E-mail:
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Ho AM, Moore RY, Lopez OL, Kuller L, Becker JT. Basal forebrain atrophy is a presymptomatic marker for Alzheimer's disease. Alzheimers Dement 2008; 4:271-9. [PMID: 18631978 PMCID: PMC2517158 DOI: 10.1016/j.jalz.2008.04.005] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2007] [Revised: 01/28/2008] [Accepted: 04/15/2008] [Indexed: 02/03/2023]
Abstract
BACKGROUND Alzheimer's disease (AD) is the most common degenerative neurologic disorder. The onset of symptoms is insidious and follows a long period of progression of an asymptomatic pathology that proceeds in a precise anatomic and temporal sequence. Recent studies with quantitative magnetic resonance imaging techniques have shown the localization of the in vivo pathology of AD and its antecedent, mild cognitive impairment. The objective of the present study was to determine whether a sensitive and reliable marker for the presymptomatic phase of the disorder could be identified by longitudinal analysis of an initially asymptomatic, community-based population. METHODS One hundred forty-eight healthy, cognitively normal participants in the Cardiovascular Health Study-Cognition Study had detailed clinical examinations and magnetic resonance imaging scans in 1998-1999 and 2002-2003. Modulated voxel-based morphometry was used to compare regional brain volumes in subjects who remained cognitively normal after 5 to 6 years of follow-up (n = 127) with those who developed probable AD during the same period (n = 21). RESULTS Among normal subjects destined to develop AD, there was significant atrophy in the basal forebrain area as long as 4.5 years before the development of clinical symptoms. When the left hippocampus was also atrophic, the onset of dementia typically occurred earlier than in cases in which the atrophy was confined to basal forebrain. CONCLUSIONS Atrophy in the basal forebrain precedes the development of AD in subjects with cognition judged to be normal by neuropsychological testing. The time required to develop dementia appears to be shortened if hippocampal atrophy is also present. These data indicate that atrophy restricted to medial basal forebrain is a biomarker that predicts development of probable AD in asymptomatic elderly subjects.
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Affiliation(s)
- Andrew M. Ho
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Robert Y. Moore
- Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA
- Department of Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Oscar L. Lopez
- Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Lewis Kuller
- Department of Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - James T. Becker
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA
- Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA
- Department of Psychology, University of Pittsburgh School of Medicine, Pittsburgh, PA
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Raizada RDS, Richards TL, Meltzoff A, Kuhl PK. Socioeconomic status predicts hemispheric specialisation of the left inferior frontal gyrus in young children. Neuroimage 2008; 40:1392-401. [PMID: 18308588 PMCID: PMC2679945 DOI: 10.1016/j.neuroimage.2008.01.021] [Citation(s) in RCA: 146] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2007] [Revised: 12/12/2007] [Accepted: 01/10/2008] [Indexed: 11/17/2022] Open
Abstract
Reading is a complex skill that is not mastered by all children. At the age of 5, on the cusp of prereading development, many factors combine to influence a child's future reading success, including neural and behavioural factors such as phonological awareness and the auditory processing of phonetic input, and environmental factors, such as socioeconomic status (SES). We investigated the interactions between these factors in 5-year-old children by administering a battery of standardised cognitive and linguistic tests, measuring SES with a standardised scale, and using fMRI to record neural activity during a behavioral task, rhyming, that is predictive of reading skills. Correlation tests were performed, and then corrected for multiple comparisons using the false discovery rate (FDR) procedure. It emerged that only one relationship linking neural with behavioural or environmental factors survived as significant after FDR correction: a correlation between SES and the degree of hemispheric specialisation in the left inferior frontal gyrus (IFG), a region which includes Broca's area. This neural-environmental link remained significant even after controlling for the children's scores on the standardised language and cognition tests. In order to investigate possible environmental influences on the left IFG further, grey and white matter volumes were calculated. Marginally significant correlations with SES were found, indicating that environmental effects may manifest themselves in the brain anatomically as well as functionally. Collectively, these findings suggest that the weaker language skills of low-SES children are related to reduced underlying neural specialisation, and that these neural problems go beyond what is revealed by behavioural tests alone.
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Affiliation(s)
- Rajeev D S Raizada
- Institute for Learning and Brain Sciences, University of Washington, Box 357988, Seattle, WA 98195, USA.
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14
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Rosano C, Aizenstein HJ, Studenski S, Newman AB. A regions-of-interest volumetric analysis of mobility limitations in community-dwelling older adults. J Gerontol A Biol Sci Med Sci 2007; 62:1048-55. [PMID: 17895446 DOI: 10.1093/gerona/62.9.1048] [Citation(s) in RCA: 131] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND In community-dwelling older adults, greater mobility impairment is associated with greater burden of diffuse brain structural abnormalities, such as higher white matter hyperintensities. This study examined the association between gray matter volumes of regions related to motor control, gait, and balance and whether this association is independent of burden of white matter hyperintensities. METHODS A random sample of 327 participants of the Cardiovascular Health Study (78.3 +/- 4.1 years old, 57% women) contributed brain magnetic resonance imaging (MRI) and mobility data. A brain imaging automated method measured gray matter volume in cerebellum, basal ganglia, and prefrontal and parietal cortex in both hemispheres. Gait speed was measured while walking 15 feet at usual pace. Standing balance was assessed by timing tandem stance. Associations between each region's volume and gait speed or balance were measured before and after adjustment for demographics, head size, cardiovascular risk factors, and 0-9 grading scores of white matter hyperintensities. RESULTS Smaller left cerebellum and left prefrontal regions were associated with slower gait, independently of covariates and of white matter hyperintensities. Smaller right putamen, right posterior superior parietal cortex, and both left and right cerebellum were associated with balance difficulty, independently of covariates and white matter hyperintensities. CONCLUSIONS Smaller gray matter volumes in regions crucial for motor control are associated with slower gait and poorer balance, and the association appears to be independent of other diffuse brain abnormalities such as white matter hyperintensities.
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Affiliation(s)
- Caterina Rosano
- School of Public Health, Department of Epidemiology, University of Pittsburgh, Pennsylvania, USA.
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15
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Rosano C, Aizenstein HJ, Wu M, Newman AB, Becker JT, Lopez OL, Kuller LH. Focal atrophy and cerebrovascular disease increase dementia risk among cognitively normal older adults. J Neuroimaging 2007; 17:148-55. [PMID: 17441836 DOI: 10.1111/j.1552-6569.2007.00093.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE This study investigated the association of medial temporal lobe (MTL) atrophy and cerebrovascular disease (white matter hyperintensities [WMH], subclinical infarcts) with the risk of developing Alzheimer's disease (AD) among cognitively normal older adults. METHODS Risk of developing AD was examined for 155 cognitively normal older adults (77.4 years, 60% women, 81% white). The MTL volumes and the presence of WMH and of subclinical infarcts were determined from brain magnetic resonance imaging (MRI) at the beginning of the study. Follow-up cognitive evaluations (average 4.3 years) identified those who developed AD. RESULTS The presence of either MTL atrophy or subclinical infarcts was independently and significantly associated with a greater risk to develop AD (OR [95% CI]: 4.4 [1.5, 12.3] and 2.7 [1.0, 7.1], respectively). In addition, those participants with both MTL atrophy and at least one brain infarct had a 7-fold increase in the risk of developing AD (OR [95% CI]: 7.0 [1.5, 33.1]), compared to those who had neither of these conditions. CONCLUSIONS In cognitively normal older adults, markers of neurodegeneration (as reflected by MTL atrophy) and of cerebrovascular disease (as reflected by infarcts on MRI) independently contribute to the risk to develop AD.
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Affiliation(s)
- Caterina Rosano
- School of Public Health, Department of Epidemiology, University of Pittsburgh, Pennysylvania, USA.
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16
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Kuller LH. Dementia epidemiology research: it is time to modify the focus of research. J Gerontol A Biol Sci Med Sci 2007; 61:1314-8. [PMID: 17234827 DOI: 10.1093/gerona/61.12.1314] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The incidence and prevalence of dementia are increasing. There is an urgent need to develop a preventive strategy. The identification of modifiable risk factors must therefore be a high priority. Newer imaging techniques provide an opportunity to identify subclinical manifestations of "dementias" that can be limited to the risk factors and subsequent clinical disease. The contribution of vascular disease to dementia and Alzheimer's disease (AD) should be a high priority as it offers a potential preventive strategy. Study designs need to be modified, including a greater emphasis on geographic variations in AD and dementia based on imaging studies, longitudinal studies of successful aging without cardiovascular disease (CVD) or AD, gene-environment interactions, and studies of unique populations that may be at lower risk because of specific lifestyles. Primary prevention trials for vascular disease should include a dementia component. Most, if not all, studies should include newer imaging studies.
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Affiliation(s)
- Lewis H Kuller
- Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pennsylvania 15213, USA.
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17
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Wu M, Rosano C, Butters M, Whyte E, Nable M, Crooks R, Meltzer CC, Reynolds CF, Aizenstein3 HJ. A fully automated method for quantifying and localizing white matter hyperintensities on MR images. Psychiatry Res 2006; 148:133-42. [PMID: 17097277 PMCID: PMC1761950 DOI: 10.1016/j.pscychresns.2006.09.003] [Citation(s) in RCA: 152] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2005] [Revised: 06/16/2006] [Accepted: 09/11/2006] [Indexed: 12/25/2022]
Abstract
White matter hyperintensities (WMH), commonly found on T2-weighted FLAIR brain MR images in the elderly, are associated with a number of neuropsychiatric disorders, including vascular dementia, Alzheimer's disease, and late-life depression. Previous MRI studies of WMHs have primarily relied on the subjective and global (i.e., full-brain) ratings of WMH grade. In the current study we implement and validate an automated method for quantifying and localizing WMHs. We adapt a fuzzy-connected algorithm to automate the segmentation of WMHs and use a demons-based image registration to automate the anatomic localization of the WMHs using the Johns Hopkins University White Matter Atlas. The method is validated using the brain MR images acquired from eleven elderly subjects with late-onset late-life depression (LLD) and eight elderly controls. This dataset was chosen because LLD subjects are known to have significant WMH burden. The volumes of WMH identified in our automated method are compared with the accepted gold standard (manual ratings). A significant correlation of the automated method and the manual ratings is found (P<0.0001), thus demonstrating similar WMH quantifications of both methods. As has been shown in other studies (e.g. [Taylor, W.D., MacFall, J.R., Steffens, D.C., Payne, M.E., Provenzale, J.M., Krishnan, K.R., 2003. Localization of age-associated white matter hyperintensities in late-life depression. Progress in Neuro-Psychopharmacology and Biological Psychiatry. 27 (3), 539-544.]), we found there was a significantly greater WMH burden in the LLD subjects versus the controls for both the manual and automated method. The effect size was greater for the automated method, suggesting that it is a more specific measure. Additionally, we describe the anatomic localization of the WMHs in LLD subjects as well as in the control subjects, and detect the regions of interest (ROIs) specific for the WMH burden of LLD patients. Given the emergence of large NeuroImage databases, techniques, such as that described here, will allow for a better understanding of the relationship between WMHs and neuropsychiatric disorders.
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Affiliation(s)
- Minjie Wu
- Department of Electrical and Computer Engineering
| | | | | | | | | | | | | | | | - Howard J. Aizenstein3
- * Correspondence should be addressed to: Howard J. Aizenstein, M.D., Ph.D., Western Psychiatric Institute and Clinic, 3811 O’Hara Street, Pittsburgh, PA 15213, USA, Tel: (412) 624-4997, Fax: (412) 624-0223,
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18
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Lopez-Garcia P, Aizenstein HJ, Snitz BE, Walter RP, Carter CS. Automated ROI-based brain parcellation analysis of frontal and temporal brain volumes in schizophrenia. Psychiatry Res 2006; 147:153-61. [PMID: 16949259 DOI: 10.1016/j.pscychresns.2006.04.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2005] [Revised: 04/05/2006] [Accepted: 04/10/2006] [Indexed: 11/24/2022]
Abstract
Structural MRI studies of schizophrenia have yielded a diversity of findings. To help characterize regional gray matter changes in schizophrenia, we used an automated region of interest (ROI)-based approach that targeted frontal and temporal regions in schizophrenia patients. The sample compromised 43 schizophrenia patients (21 chronic patients, 22 unmedicated first episode patients), 20 first episode non-schizophrenia psychosis patients and 47 comparison subjects. Automated regional volume measurement was performed in 22 ROIs, including frontal and temporal cortical subregions and hippocampus. Correlations between volume measures, duration of illness and clinical scores were evaluated. Chronic schizophrenia patients showed gray matter volume differences in left dorsolateral prefrontal cortex (DLPFC) and right supplementary motor area (SMA). First episode psychosis patients presented smaller right anterior cingulate cortex (ACC) and left DLPFC than comparison subjects. Disorganization scores and duration of illness correlated negatively with gray matter volume of DLPFC and SMA in chronic schizophrenia patients. Using an automated ROI-based method, we found volume reductions in lateral and medial frontal regions in both first episode and chronic schizophrenia. The automated ROI-based method can be used as a valid and efficient tool for quantification of regional gray matter volume in schizophrenia in multiple ROIs across the brains of large numbers of subjects.
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Affiliation(s)
- Pilar Lopez-Garcia
- Department of Psychiatry, School of Medicine, University of California, Davis, United States.
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19
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Wu M, Carmichael O, Lopez‐Garcia P, Carter CS, Aizenstein HJ. Quantitative comparison of AIR, SPM, and the fully deformable model for atlas-based segmentation of functional and structural MR images. Hum Brain Mapp 2006; 27:747-54. [PMID: 16463385 PMCID: PMC2886594 DOI: 10.1002/hbm.20216] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Typical packages used for coregistration in functional image analyses include automated image registration (AIR) and statistical parametric mapping (SPM). However, both methods have limited-dimension deformation models. A fully deformable model, which combines the piecewise linear registration for coarse alignment with demons algorithm for voxel-level refinement, allows a higher degree of spatial deformation. This leads to a more accurate colocalization of the functional signal from different subjects and therefore can produce a more reliable group average signal. We quantitatively compared the performance of the three different registration approaches through a series of experiments and we found that the fully deformable model consistently produces a more accurate structural segmentation and a more reliable functional signal colocalization than does AIR or SPM.
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Affiliation(s)
- Minjie Wu
- Department of Electrical and Computer Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Owen Carmichael
- Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania
- Robotics Institute, Carnegie Mellon University, Pittsburgh, Pennsylvania
| | - Pilar Lopez‐Garcia
- Department of Psychiatry, University of California at Davis, Davis, California
| | - Cameron S. Carter
- Department of Psychiatry, University of California at Davis, Davis, California
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Abstract
Biological aging of the brain is partly attributable to aging of the cerebrovascular circulation and the effects of these vascular changes on the brain. A variety of techniques ranging from simple, clinical scores to complex radiological techniques have been used in an attempt to understand, describe and quantify this process. Simultaneously attempts have been made to relate these changes to cognitive and physical changes and the risk of dementia and stroke associated with brain aging. The most frequently used clinical scores are the Framingham Stroke Risk Profile and the Hachinski Ischemic Score for vascular dementia. Radiological techniques to estimate cerebrovascular burden include many varieties of ultrasonographic, computerized tomography (CT), magnetic resonance imaging (MRI) and nuclear medicine techniques. The radiological techniques evaluate the nature and extent of disease in the vessels supplying the brain and the pattern and extent of radiological evidence of damage to the brain both on static and dynamic imaging and are briefly outlined in this review. There are several studies using these techniques to study 'normal' aging populations, and the techniques used in the most widely known of these studies are briefly highlighted in this review.
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Affiliation(s)
- Sudha Seshadri
- Department of Neurology, School of Medicine, Boston University, Boston, USA.
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White matter grade and ventricular volume on brain MRI as markers of longevity in the cardiovascular health study. Neurobiol Aging 2006; 28:1307-15. [PMID: 16857296 DOI: 10.1016/j.neurobiolaging.2006.06.010] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2006] [Revised: 03/29/2006] [Accepted: 06/02/2006] [Indexed: 11/15/2022]
Abstract
High white matter grade (WMG) on magnetic resonance imaging (MRI) is a risk factor for dementia, stroke and disability. Higher ventricular size is a marker of brain "atrophy." In the Cardiovascular Health Study (CHS) (n=3245) mean age 75 years, 50% black and 40% men, we evaluated WM and ventricular grade (VG), total, cardiovascular and noncardiovascular mortality and longevity before and after adjusting for numerous determinants of longevity over an approximate 10-12 years of follow-up. A low WMG and VG was a marker for low total, cardiovascular and noncardiovascular mortality and for increased longevity over 10+ years of follow-up. We estimated that a 75-year-old with WMG below median would have about a 5-6 years greater longevity and for VG about 3 years, than above the median even after adjustment for numerous risk factors. Low WMG and VG on MRI is a powerful determinant of long-term survival among older individuals.
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22
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Wagner A, Aizenstein H, Frank GK, Figurski J, May JC, Putnam K, Fischer L, Bailer UF, Henry SE, McConaha C, Vogel V, Kaye WH. Neural correlates of habituation to taste stimuli in healthy women. Psychiatry Res 2006; 147:57-67. [PMID: 16806849 DOI: 10.1016/j.pscychresns.2005.11.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2005] [Revised: 08/30/2005] [Accepted: 11/08/2005] [Indexed: 11/21/2022]
Abstract
Recent studies show that specific regions of the cortex contribute to modulation of appetitive behaviors. The purpose of this study was to determine whether neural response in these regions changes over time when a taste stimulus is administered repeatedly. Such a paradigm may be useful for determining whether altered habituation contributes to disturbed eating behavior. This study used a programmable syringe pump to compare administration of a 10% sucrose solution to distilled water in 11 healthy female subjects using functional magnetic resonance imaging. The stimuli were presented in either a sequential or pseudorandom order. An a priori 'Region of Interest' (ROI) based analysis method was used, with ROIs defined in the prefrontal cortex, insula, amygdala, and hippocampus. To test habituation, activation during the first half of each block was compared with activation during the second half. For the pseudorandom blocks, subjects showed habituation in almost all ROIs to water, but in none to sucrose. By contrast, for sequential blocks, both stimuli produced habituation in taste-related brain regions. These data suggest that habituation patterns in healthy subjects may depend on frequency and regularity of stimulus administration.
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Affiliation(s)
- Angela Wagner
- University of Pittsburgh, School of Medicine, Department of Psychiatry, Western Psychiatric Institute and Clinic, PA 15213, USA
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23
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Commentary on “The NIH Cognitive and Emotional Health Project. Report of the Critical Evaluation Study Committee”. Alzheimers Dement 2006; 2:33-5. [DOI: 10.1016/j.jalz.2005.12.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Rosano C, Brach J, Longstreth WT, Newman AB. Quantitative Measures of Gait Characteristics Indicate Prevalence of Underlying Subclinical Structural Brain Abnormalities in High-Functioning Older Adults. Neuroepidemiology 2005; 26:52-60. [PMID: 16254454 DOI: 10.1159/000089240] [Citation(s) in RCA: 142] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Abnormal gait in high-functioning older adults may indicate underlying subtle structural brain abnormalities. We tested the hypothesis that temporal and spatial parameters of gait, including speed, stride length and double support time, are cross-sectionally associated with white matter hyperintensity, subcortical infarcts or brain atrophy on brain MRI. We examined 321 men and women (mean age = 78.3) participating to the Cardiovascular Health Study who were free of dementia or stroke at the time of the gait assessment. Analyses were set with gait as independent variable and brain MRIs as dependent variables. Gait measures were determined from the footfalls recorded on a 4-meter-long instrumented walking surface, the GaitMat II. Brain MRIs were examined for the presence of white matter hyperintensity (WMG, graded from 0 to 9), brain infarcts (predominantly subcortical) and ventricular enlargement (graded from 0 to 9). Slower gait, shorter stride length and longer double support times were associated with greater prevalence of white matter grade > or =3 (p = 0.02), and at least 1 brain infarct (p = 0.04) independent of age. In multivariate logistic regression models adjusted for demographics and clinical cardiovascular diseases, those with gait speed <1.02 m/s were more likely to have WMG > or =3 and at least 1 brain infarct, compared with those with faster gait - odds ratio (OR): 2.85, 95% confidence interval (95% CI): 1.35, 6.02, and OR: 2.09, 95% CI: 1.04, 4.19. Shorter stride length was also associated with greater probability of having at least 1 brain infarct (gait stride <0.88 vs. >1.10 m: OR: 3.20, 95% CI: 1.49, 6.88), while longer double support times were associated with a greater probability of having WMG > or =3 (double support time >0.19 vs. <0.14 s: OR: 2.3, 95% CI: 1.1, 4.7) independent of demographics and clinical cardiovascular diseases. Gait parameters were not significantly associated with ventricular grade. In summary, in this group of high-functioning older adults, poorer gait speed, shorter stride and longer double support time are associated with high white matter disease and subclinical strokes.
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Affiliation(s)
- Caterina Rosano
- Division of Geriatric Medicine, Department of Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA.
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25
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Current awareness in geriatric psychiatry. Int J Geriatr Psychiatry 2005; 20:1206-13. [PMID: 16397968 DOI: 10.1002/gps.1232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Rosano C, Aizenstein H, Cochran J, Saxton J, De Kosky S, Newman AB, Kuller LH, Lopez OL, Carter CS. Functional neuroimaging indicators of successful executive control in the oldest old. Neuroimage 2005; 28:881-9. [PMID: 16226041 DOI: 10.1016/j.neuroimage.2005.05.059] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2004] [Revised: 05/13/2005] [Accepted: 05/17/2005] [Indexed: 11/17/2022] Open
Abstract
Attentional control, motor planning abilities, and executive cognitive functions (ECF) rapidly decline with age. In particular, older adults experience difficulty in manipulating selected motor responses in the presence of conflicting or distracting information. To examine age-related changes in the neural substrates of the attentional and motor planning components of ECF, we assessed the patterns of brain activation in 8 cognitively normal older adults (mean age 81.5) and 20 young individuals (mean age 23.0) while they responded to low and high loads of attentional demands of the Preparing to Overcome Prepotency (POP) task. In the POP task, the selection of one out of two possible motor responses in the presence of increasing attentional task loads determines the accuracy of the performance. Older individuals were slower than young adults (P < 0.001) but achieved a strikingly high accuracy similar to the young group (P = 0.2), regardless of the task load. Both groups showed a load-related fMRI signal increase in the anterior cingulate cortex (ACC), posterior parietal cortex (PPC: Brodmann areas 7 and 40), and dorsolateral prefrontal cortex (dLPFC: Brodmann areas 9, 45, and 46) bilaterally. Compared to young individuals, older adults had lower activation in dLPFC (Brodmann areas 9, 45, and 46: P = 0.007, P = 0.043, and P = 0.040) and Brodmann area 7, P = 0.002. Activation in Brodmann areas 40 and ACC was similar in the two groups (P > 0.05). Among older adults, the most successful performers were those who responded to increasing task loads with greater activation in PPC (Brodmann area 40), despite lower dLPFC activation. Older adults who are able to perform executive control tasks as well as young adults, also seem to implement speed-accuracy trade-off strategies which may rely on increased parietal activation.
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Affiliation(s)
- C Rosano
- School of Public Health, Department of Epidemiology, University of Pittsburgh, PA 15260, USA
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27
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Rosano C, Aizenstein HJ, Cochran JL, Saxton JA, De Kosky ST, Newman AB, Kuller LH, Lopez OL, Carter CS. Event-related functional magnetic resonance imaging investigation of executive control in very old individuals with mild cognitive impairment. Biol Psychiatry 2005; 57:761-7. [PMID: 15820233 PMCID: PMC2848401 DOI: 10.1016/j.biopsych.2004.12.031] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2004] [Revised: 11/30/2004] [Accepted: 12/09/2004] [Indexed: 11/29/2022]
Abstract
BACKGROUND Attentional control of executive cognitive function (ECF) decreases in older individuals with Alzheimer Disease (AD). In order to examine early AD-related changes in the neural substrates of ECF attentional control, we measured activation dorsolateral prefrontal (dLPFC), posterior parietal (PPC), and anterior cingulate cortex (ACC) in adults with mild cognitively impairment (MCI) and in cognitively normal (CN) adults. METHODS Functional magnetic resonance imaging analysis of brain activation in MCI (n = 8, mean age 79.5) and CN (n = 8 mean age 81.5) during increasing loads of attentional demands. RESULTS MCI and CN older adults performed with similar accuracy and reaction time. MCI had greater activation than CN in PPC (right p = .03 and left p = .05) and dlPFC areas (right p = .002 and left p = .004), while activation in ACC was similar in the two groups. Response to increasing loads of the task differed by group: MCI selectively engaged bilateral PPC (right p = .03, left p = .04), while CN subjects increased bilateral dlPFC activation (right p = .005 and left p = .02) and ACC activation (p = .04). Among MCI, greater load-related changes in PPC activity were associated with smaller load-related changes in accuracy rates (r = -.85, p = .07) and greater increases in reaction times (r = .97, p = .01). In CN subjects, load-related change in PPC activation was associated with load-related change in reaction time (r = .76, p = .02) but not with changes in accuracy rates. CONCLUSIONS PPC and dlPFC may show early functional changes associated with MCI.
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Affiliation(s)
- Caterina Rosano
- School of Public Health, Department of Epidemiology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
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