1
|
Bulgarelli C, Blasi A, McCann S, Milosavljevic B, Ghillia G, Mbye E, Touray E, Fadera T, Acolatse L, Moore SE, Lloyd-Fox S, Elwell CE, Eggebrecht AT. Growth in early infancy drives optimal brain functional connectivity which predicts cognitive flexibility in later childhood. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.02.573930. [PMID: 38260280 PMCID: PMC10802370 DOI: 10.1101/2024.01.02.573930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Functional brain network organization, measured by functional connectivity (FC), reflects key neurodevelopmental processes for healthy development. Early exposure to adversity, e.g. undernutrition, affects neurodevelopment, observable via disrupted FC, and leads to poorer outcomes from preschool age onward. We assessed longitudinally the impact of early growth trajectories on developmental FC in a rural Gambian population from age 5 to 24 months. To investigate how these early trajectories relate to later childhood outcomes, we assessed cognitive flexibility at 3-5 years. We observed that early physical growth before the fifth month of life drove optimal developmental trajectories of FC that in turn predicted cognitive flexibility at pre-school age. In contrast to previously studied developmental populations, this Gambian sample exhibited long-range interhemispheric FC that decreased with age. Our results highlight the measurable effects that poor growth in early infancy has on brain development and the subsequent impact on pre-school age cognitive development, underscoring the need for early life interventions throughout global settings of adversity.
Collapse
Affiliation(s)
- Chiara Bulgarelli
- Centre for Brain and Cognitive Development, Birkbeck, University of London, UK
- Department of Medical Physics and Biomedical Engineering, University College London, UK
| | - Anna Blasi
- Department of Medical Physics and Biomedical Engineering, University College London, UK
| | - Samantha McCann
- Department of Women and Children’s Health, King’s College London, UK
- Medical Research Council Unit The Gambia at the London School of Hygiene and Tropical Medicine, The Gambia
| | - Bosiljka Milosavljevic
- Department of Psychology, University of Cambridge, UK
- School of Biological and Experimental Psychology, Queen Mary University of London, UK
| | - Giulia Ghillia
- Department of Women and Children’s Health, King’s College London, UK
| | - Ebrima Mbye
- Medical Research Council Unit The Gambia at the London School of Hygiene and Tropical Medicine, The Gambia
| | - Ebou Touray
- Medical Research Council Unit The Gambia at the London School of Hygiene and Tropical Medicine, The Gambia
| | - Tijan Fadera
- Medical Research Council Unit The Gambia at the London School of Hygiene and Tropical Medicine, The Gambia
| | - Lena Acolatse
- Medical Research Council Unit The Gambia at the London School of Hygiene and Tropical Medicine, The Gambia
- Nutrition Innovation Centre for Food and Health, School of Biomedical Sciences, Ulster University, Ireland
| | - Sophie E. Moore
- Department of Women and Children’s Health, King’s College London, UK
- Medical Research Council Unit The Gambia at the London School of Hygiene and Tropical Medicine, The Gambia
| | | | - Clare E. Elwell
- Department of Medical Physics and Biomedical Engineering, University College London, UK
| | - Adam T. Eggebrecht
- Mallinckrodt Institute of Radiology, Washington University School of Medicine in St. Louis, USA
| | - BRIGHT Study Team
- The BRIGHT team are (in alphabetic order): Muhammed Ceesay, Kassa Kora, Fabakary Njai, Andrew Prentice, Mariama Saidykhan
| |
Collapse
|
2
|
Coray RC, Zimmermann J, Haugg A, Baumgartner MR, Steuer AE, Seifritz E, Stock AK, Beste C, Cole DM, Quednow BB. The functional connectome of 3,4-methyldioxymethamphetamine-related declarative memory impairments. Hum Brain Mapp 2023; 44:5079-5094. [PMID: 37530403 PMCID: PMC10502674 DOI: 10.1002/hbm.26438] [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: 02/14/2023] [Revised: 06/30/2023] [Accepted: 07/14/2023] [Indexed: 08/03/2023] Open
Abstract
The chronic intake of 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") bears a strong risk for sustained declarative memory impairments. Although such memory deficits have been repeatedly reported, their neurofunctional origin remains elusive. Therefore, we here investigate the neuronal basis of altered declarative memory in recurrent MDMA users at the level of brain connectivity. We examined a group of 44 chronic MDMA users and 41 demographically matched controls. Declarative memory performance was assessed by the Rey Auditory Verbal Learning Test and a visual associative learning test. To uncover alterations in the whole brain connectome between groups, we employed a data-driven multi-voxel pattern analysis (MVPA) approach on participants' resting-state functional magnetic resonance imaging data. Recent MDMA use was confirmed by hair analyses. MDMA users showed lower performance in delayed recall across tasks compared to well-matched controls with moderate-to-strong effect sizes. MVPA revealed a large cluster located in the left postcentral gyrus of global connectivity differences between groups. Post hoc seed-based connectivity analyses with this cluster unraveled hypoconnectivity to temporal areas belonging to the auditory network and hyperconnectivity to dorsal parietal regions belonging to the dorsal attention network in MDMA users. Seed-based connectivity strength was associated with verbal memory performance in the whole sample as well as with MDMA intake patterns in the user group. Our findings suggest that functional underpinnings of MDMA-related memory impairments encompass altered patterns of multimodal sensory integration within auditory processing regions to a functional heteromodal connector hub, the left postcentral gyrus. In addition, hyperconnectivity in regions of a cognitive control network might indicate compensation for degraded sensory processing.
Collapse
Affiliation(s)
- Rebecca C Coray
- Experimental and Clinical Pharmacopsychology, Department of Psychiatry, Psychotherapy, and Psychosomatics, Psychiatric University Hospital Zurich, University of Zurich, Zurich, Switzerland
- Neuroscience Center Zurich, ETH Zurich and University of Zurich, Zurich, Switzerland
| | - Josua Zimmermann
- Experimental and Clinical Pharmacopsychology, Department of Psychiatry, Psychotherapy, and Psychosomatics, Psychiatric University Hospital Zurich, University of Zurich, Zurich, Switzerland
- Neuroscience Center Zurich, ETH Zurich and University of Zurich, Zurich, Switzerland
| | - Amelie Haugg
- Department of Child and Adolescent Psychiatry and Psychotherapy, Psychiatric University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Markus R Baumgartner
- Center for Forensic Hair Analytics, Institute of Forensic Medicine, University of Zurich, Zurich, Switzerland
| | - Andrea E Steuer
- Department of Forensic Pharmacology and Toxicology, Institute of Forensic Medicine, University of Zurich, Zurich, Switzerland
| | - Erich Seifritz
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland
| | - Ann-Kathrin Stock
- Cognitive Neurophysiology, Department of Child and Adolescent Psychiatry, Faculty of Medicine, TU Dresden, Dresden, Germany
| | - Christian Beste
- Cognitive Neurophysiology, Department of Child and Adolescent Psychiatry, Faculty of Medicine, TU Dresden, Dresden, Germany
| | - David M Cole
- Experimental and Clinical Pharmacopsychology, Department of Psychiatry, Psychotherapy, and Psychosomatics, Psychiatric University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Boris B Quednow
- Experimental and Clinical Pharmacopsychology, Department of Psychiatry, Psychotherapy, and Psychosomatics, Psychiatric University Hospital Zurich, University of Zurich, Zurich, Switzerland
- Neuroscience Center Zurich, ETH Zurich and University of Zurich, Zurich, Switzerland
| |
Collapse
|
3
|
Choi S, Chen Y, Zeng H, Biswal B, Yu X. Identifying the distinct spectral dynamics of laminar-specific interhemispheric connectivity with bilateral line-scanning fMRI. J Cereb Blood Flow Metab 2023; 43:1115-1129. [PMID: 36803280 PMCID: PMC10291453 DOI: 10.1177/0271678x231158434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 11/30/2022] [Accepted: 12/12/2022] [Indexed: 02/23/2023]
Abstract
Despite extensive efforts to identify interhemispheric functional connectivity (FC) with resting-state (rs-) fMRI, correlated low-frequency rs-fMRI signal fluctuation across homotopic cortices originates from multiple sources. It remains challenging to differentiate circuit-specific FC from global regulation. Here, we developed a bilateral line-scanning fMRI method to detect laminar-specific rs-fMRI signals from homologous forepaw somatosensory cortices with high spatial and temporal resolution in rat brains. Based on spectral coherence analysis, two distinct bilateral fluctuation spectral features were identified: ultra-slow fluctuation (<0.04 Hz) across all cortical laminae versus Layer (L) 2/3-specific evoked BOLD at 0.05 Hz based on 4 s on/16 s off block design and resting-state fluctuations at 0.08-0.1 Hz. Based on the measurements of evoked BOLD signal at corpus callosum (CC), this L2/3-specific 0.05 Hz signal is likely associated with neuronal circuit-specific activity driven by the callosal projection, which dampened ultra-slow oscillation less than 0.04 Hz. Also, the rs-fMRI power variability clustering analysis showed that the appearance of L2/3-specific 0.08-0.1 Hz signal fluctuation is independent of the ultra-slow oscillation across different trials. Thus, distinct laminar-specific bilateral FC patterns at different frequency ranges can be identified by the bilateral line-scanning fMRI method.
Collapse
Affiliation(s)
- Sangcheon Choi
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Harvard Medical School, Massachusetts General Hospital, Charlestown, MA, USA
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany
| | - Yi Chen
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany
| | - Hang Zeng
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany
- Graduate Training Centre of Neuroscience, University of Tübingen, Tübingen, Germany
| | - Bharat Biswal
- Department of Biomedical Engineering, NJIT, Newark, NJ, USA
| | - Xin Yu
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Harvard Medical School, Massachusetts General Hospital, Charlestown, MA, USA
| |
Collapse
|
4
|
Manno FAM, Kumar R, An Z, Khan MS, Su J, Liu J, Wu EX, He J, Feng Y, Lau C. Structural and Functional Hippocampal Correlations in Environmental Enrichment During the Adolescent to Adulthood Transition in Mice. Front Syst Neurosci 2022; 15:807297. [PMID: 35242015 PMCID: PMC8886042 DOI: 10.3389/fnsys.2021.807297] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 12/14/2021] [Indexed: 01/13/2023] Open
Abstract
Environmental enrichment is known to induce neuronal changes; however, the underlying structural and functional factors involved are not fully known and remain an active area of study. To investigate these factors, we assessed enriched environment (EE) and standard environment (SE) control mice over 30 days using structural and functional MRI methods. Naïve adult male mice (n = 30, ≈20 g, C57BL/B6J, postnatal day 60 initial scan) were divided into SE and EE groups and scanned before and after 30 days. Structural analyses included volumetry based on manual segmentation as well as diffusion tensor imaging (DTI). Functional analyses included seed-based analysis (SBA), independent component analysis (ICA), the amplitude of low-frequency fluctuation (ALFF), and fractional ALFF (fALFF). Structural results indicated that environmental enrichment led to an increase in the volumes of cornu ammonis 1 (CA1) and dentate gyrus. Structural results indicated changes in radial diffusivity and mean diffusivity in the visual cortex and secondary somatosensory cortex after EE. Furthermore, SBA and ICA indicated an increase in resting-state functional MRI (rsfMRI) functional connectivity in the hippocampus. Using parallel structural and functional analyses, we have demonstrated coexistent structural and functional changes in the hippocampal subdivision CA1. Future research should map alterations temporally during environmental enrichment to investigate the initiation of these structural and functional changes.
Collapse
Affiliation(s)
- Francis A M Manno
- Center for Imaging Science, Department of Biomedical Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, MD, United States.,Department of Physics, City University of Hong Kong, Hong Kong, Hong Kong SAR, China
| | - Rachit Kumar
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States.,Medical Scientist Training Program, University of Pennsylvania, Philadelphia, PA, United States
| | - Ziqi An
- Guangdong Provincial Key Laboratory of Medical Image Processing, School of Biomedical Engineering, Southern Medical University, Guangzhou, China.,Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Key Laboratory of Mental Health of the Ministry of Education, Southern Medical University, Guangzhou, China
| | - Muhammad Shehzad Khan
- Department of Physics, City University of Hong Kong, Hong Kong, Hong Kong SAR, China
| | - Junfeng Su
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Harvard University, Boston, MA, United States
| | - Jiaming Liu
- Guangdong Provincial Key Laboratory of Medical Image Processing, School of Biomedical Engineering, Southern Medical University, Guangzhou, China.,Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Key Laboratory of Mental Health of the Ministry of Education, Southern Medical University, Guangzhou, China
| | - Ed X Wu
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, Hong Kong SAR, China.,Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
| | - Jufang He
- Department of Neuroscience, City University of Hong Kong, Hong Kong, Hong Kong SAR, China.,Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, Hong Kong SAR, China
| | - Yanqiu Feng
- Guangdong Provincial Key Laboratory of Medical Image Processing, School of Biomedical Engineering, Southern Medical University, Guangzhou, China.,Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Key Laboratory of Mental Health of the Ministry of Education, Southern Medical University, Guangzhou, China
| | - Condon Lau
- Department of Physics, City University of Hong Kong, Hong Kong, Hong Kong SAR, China
| |
Collapse
|
5
|
Feng L, Bi X, Zhang H. Brain Regions Identified as Being Associated with Verbal Reasoning through the Use of Imaging Regression via Internal Variation. J Am Stat Assoc 2021; 116:144-158. [PMID: 34955572 DOI: 10.1080/01621459.2020.1766468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Brain-imaging data have been increasingly used to understand intellectual disabilities. Despite significant progress in biomedical research, the mechanisms for most of the intellectual disabilities remain unknown. Finding the underlying neurological mechanisms has been proved difficult, especially in children due to the rapid development of their brains. We investigate verbal reasoning, which is a reliable measure of individuals' general intellectual abilities, and develop a class of high-order imaging regression models to identify brain subregions which might be associated with this specific intellectual ability. A key novelty of our method is to take advantage of spatial brain structures, and specifically the piecewise smooth nature of most imaging coefficients in the form of high-order tensors. Our approach provides an effective and urgently needed method for identifying brain subregions potentially underlying certain intellectual disabilities. The idea behind our approach is a carefully constructed concept called Internal Variation (IV). The IV employs tensor decomposition and provides a computationally feasible substitution for Total Variation (TV), which has been considered in the literature to deal with similar problems but is problematic in high order tensor regression. Before applying our method to analyze the real data, we conduct comprehensive simulation studies to demonstrate the validity of our method in imaging signal identification. Then, we present our results from the analysis of a dataset based on the Philadelphia Neurodevelopmental Cohort for which we preprocessed the data including re-orienting, bias-field correcting, extracting, normalizing and registering the magnetic resonance images from 978 individuals. Our analysis identified a subregion across the cingulate cortex and the corpus callosum as being associated with individuals' verbal reasoning ability, which, to the best of our knowledge, is a novel region that has not been reported in the literature. This finding is useful in further investigation of functional mechansims for verbal reasoning.
Collapse
Affiliation(s)
- Long Feng
- Department of Biostatistics, Yale University
| | - Xuan Bi
- Information and Decision Sciences, Carlson School of Management, University of Minnesota
| | | |
Collapse
|
6
|
Zhang J, Chang Y, Ding S. Disrupted hypothalamic functional connectivity related to cognitive impairment after diffuse axonal injury. Medicine (Baltimore) 2021; 100:e27805. [PMID: 35049180 PMCID: PMC9191382 DOI: 10.1097/md.0000000000027805] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Accepted: 10/27/2021] [Indexed: 11/26/2022] Open
Abstract
This study aims to investigate whether there is imaging evidence of disrupted hypothalamic functional connectivity (FC) in patients with diffuse axonal injury (DAI) and relationships with cognitive impairment.Resting-state functional magnetic resonance imaging (fMRI) data were acquired from acute patients with diagnosed DAI (n = 30) and healthy controls (HC) (n = 30). We first assessed hypothalamic FC with seed-based analysis. Furthermore, the lateral and medial hypothalamic seed was selected to show distinct functional connectivity in DAI. In addition, partial correlation was used to measure the clinical associations with the altered hypothalamic FC in DAI patients.Compared with HC, DAI group showed significantly increased hypothalamic FC with superior temporal gyrus, and the regions around the operculum. Furthermore, there was a significant negative correlation between the connectivity coefficient of hypothalamus to right and left superior temporal gyrus and the disability rating scale scores in DAI group. When the seed regions were divided into lateral and medial hypothalamus, except for increased connectivity of medial hypothalamus (P < .01 with correction), we more observed that decreased left lateral hypothalamic connectivity was positively correlated with mini-mental state examination (MMSE) scores.Our results suggest that there are alterations of hypothalamic FC in DAI and offer further understanding of clinical symptoms including related cognitive impairment.
Collapse
|
7
|
Manno FAM, An Z, Kumar R, Wu EX, He J, Feng Y, Lau C. Structural Alterations in a Rat Model of Short-Term Conductive Hearing Loss Are Associated With Reduced Resting State Functional Connectivity. Front Syst Neurosci 2021; 15:655172. [PMID: 34456689 PMCID: PMC8397539 DOI: 10.3389/fnsys.2021.655172] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 07/02/2021] [Indexed: 12/14/2022] Open
Abstract
Conductive hearing loss (CHL) results in attenuation of air conducted sound reaching the inner ear. How a change in air conducted sound alters the auditory system resulting in cortical alterations is not well understood. Here, we have assessed structural and functional magnetic resonance imaging (MRI) in an adult (P60) rat model of short-term conductive hearing loss (1 week). Diffusion tensor imaging (DTI) revealed fractional anisotropy (FA) and axial diffusivity alterations after hearing loss that circumscribed the auditory cortex (AC). Tractography found the lateral lemniscus tract leading to the bilateral inferior colliculus (IC) was reduced. For baseline comparison, DTI and tractography alterations were not found for the somatosensory cortex. To determine functional connectivity changes due to hearing loss, seed-based analysis (SBA) and independent component analysis (ICA) were performed. Short term conductive hearing loss altered functional connectivity in the AC and IC, but not the somatosensory cortex. The results present an exploratory neuroimaging assessment of structural alterations coupled to a change in functional connectivity after conductive hearing loss. The results and implications for humans consist of structural-functional brain alterations following short term hearing loss in adults.
Collapse
Affiliation(s)
| | - Ziqi An
- Guangdong Provincial Key Laboratory of Medical Image Processing, School of Biomedical Engineering, Southern Medical University, Guangzhou, China
- Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Southern Medical University, Guangzhou, China
| | - Rachit Kumar
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Medical Scientist Training Program, University of Pennsylvania, Philadelphia, PA, United States
| | - Ed X. Wu
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, SAR China
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong, SAR China
| | - Jufang He
- Department of Neuroscience, City University of Hong Kong, Hong Kong, SAR China
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, SAR China
| | - Yanqiu Feng
- Guangdong Provincial Key Laboratory of Medical Image Processing, School of Biomedical Engineering, Southern Medical University, Guangzhou, China
- Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Southern Medical University, Guangzhou, China
| | - Condon Lau
- Department of Physics, City University of Hong Kong, Hong Kong, SAR China
| |
Collapse
|
8
|
Wang Y, Zhou F, Li Y, Li J, Kuang H, Chen Q, Hong T, Gong H. Functional plasticity in lateral hypothalamus and its prediction of cognitive impairment in patients with diffuse axonal injury: evidence from a resting-state functional connectivity study. Neuroreport 2021; 32:588-595. [PMID: 33850090 DOI: 10.1097/wnr.0000000000001630] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
OBJECTIVE Diffuse axonal injury (DAI) is a common pathological process after traumatic brain injury, which may cause survivors severe functional disorders, including cognitive impairment and physical disability. Recent literature indicated lateral hypothalamus and medial hypothalamus damage during DAI. Thus, we aim to investigate whether there is imaging evidence of hypothalamic injury in patients with DAI and its clinical association. METHODS Twenty-four patients with diagnosed DAI and 26 age and sex-matched healthy controls underwent resting-state functional MRI. We assessed the lateral hypothalamus and medial hypothalamus functional connectivity with seed-based analysis in DAI. Furthermore, a partial correlation was used to measure its clinical association. The prediction of the severity of DAI from the altered lateral hypothalamus and medial hypothalamus connectivity was conducted using a general linear model. RESULTS Compared with healthy control, the DAI group showed significantly decreased lateral hypothalamus functional connectivity with the basal ganglia and cingulate gyrus, which was positively correlated with mini-mental state examination scores (Bonferroni correction at P < 0.0125). Importantly, this disrupted functional connectivity can be used to predict the patients' cognitive state reliably (P = 0.006; P = 0.009, respectively) in DAI. Moreover, we also observed increased connectivity of medial hypothalamus with the superior temporal gyrus and the regions around the operculum. Furthermore, there was a trend of negative correlation between the medial hypothalamus functional connectivity changes to the right superior temporal gyrus and the disability rating scale scores in the DAI group. CONCLUSION Our results suggest that there are alterations of medial hypothalamus and lateral hypothalamus connectivity in DAI and further understand its clinical symptoms, including related cognitive impairment.
Collapse
Affiliation(s)
- Yao Wang
- Department of Radiology, The First Affiliated Hospital, Nanchang University
- Neuroimaging Lab, Jiangxi Province Medical Imaging Research Institute
| | - Fuqing Zhou
- Department of Radiology, The First Affiliated Hospital, Nanchang University
- Neuroimaging Lab, Jiangxi Province Medical Imaging Research Institute
| | - Yan Li
- Department of Radiology, The First Affiliated Hospital, Nanchang University
- Neuroimaging Lab, Jiangxi Province Medical Imaging Research Institute
| | - Jian Li
- Department of Radiology, The First Affiliated Hospital, Nanchang University
- Neuroimaging Lab, Jiangxi Province Medical Imaging Research Institute
| | - Hongmei Kuang
- Department of Radiology, The First Affiliated Hospital, Nanchang University
- Neuroimaging Lab, Jiangxi Province Medical Imaging Research Institute
| | - Qi Chen
- Department of Radiology, The First Affiliated Hospital, Nanchang University
- Neuroimaging Lab, Jiangxi Province Medical Imaging Research Institute
| | - Tao Hong
- Department of Neurosurgery, The First Affiliated Hospital, Nanchang University, Nanchang, People's Republic of China
| | - Honghan Gong
- Department of Radiology, The First Affiliated Hospital, Nanchang University
- Neuroimaging Lab, Jiangxi Province Medical Imaging Research Institute
| |
Collapse
|
9
|
Yao S, Becker B, Kendrick KM. Reduced Inter-hemispheric Resting State Functional Connectivity and Its Association With Social Deficits in Autism. Front Psychiatry 2021; 12:629870. [PMID: 33746796 PMCID: PMC7969641 DOI: 10.3389/fpsyt.2021.629870] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 02/11/2021] [Indexed: 02/06/2023] Open
Abstract
Autism spectrum disorder (ASD) is an early onset developmental disorder which persists throughout life and is increasing in prevalence over the last few decades. Given its early onset and variable cognitive and emotional functional impairments, it is generally challenging to assess ASD individuals using task-based behavioral and functional MRI paradigms. Consequently, resting state functional MRI (rs-fMRI) has become a key approach for examining ASD-associated neural alterations and revealed functional alterations in large-scale brain networks relative to typically developing (TD) individuals, particularly those involved in social-cognitive and affective processes. Recent progress suggests that alterations in inter-hemispheric resting state functional connectivity (rsFC) between regions in the 2 brain hemispheres, particularly homotopic ones, may be of great importance. Here we have reviewed neuroimaging studies examining inter-hemispheric rsFC abnormities in ASD and its associations with symptom severity. As an index of inter-hemispheric functional connectivity, we have additionally reviewed previous studies on corpus callosum (CC) volumetric and fiber changes in ASD. There are converging findings on reduced inter-hemispheric (including homotopic) rsFC in large-scale brain networks particularly in posterior hubs of the default mode network, reduced volumes in the anterior and posterior CC, and on decreased FA and increased MD or RD across CC subregions. Associations between the strength of inter-hemispheric rsFC and social impairments in ASD together with their classification performance in distinguishing ASD subjects from TD controls across ages suggest that the strength of inter-hemispheric rsFC may be a more promising biomarker for assisting in ASD diagnosis than abnormalities in either brain wide rsFC or brain structure.
Collapse
Affiliation(s)
- Shuxia Yao
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Laboratory for NeuroInformation, Center for Information in Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Benjamin Becker
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Laboratory for NeuroInformation, Center for Information in Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Keith M Kendrick
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Laboratory for NeuroInformation, Center for Information in Medicine, University of Electronic Science and Technology of China, Chengdu, China
| |
Collapse
|
10
|
Mapping the living mouse brain neural architecture: strain-specific patterns of brain structural and functional connectivity. Brain Struct Funct 2021; 226:647-669. [PMID: 33635426 DOI: 10.1007/s00429-020-02190-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 11/27/2020] [Indexed: 10/22/2022]
Abstract
Mapping brain structural and functional connectivity (FC) became an essential approach in neuroscience as network properties can underlie behavioral phenotypes. In mouse models, revealing strain-related patterns of brain wiring is crucial, since these animals are used to answer questions related to neurological or neuropsychiatric disorders. C57BL/6 and BALB/cJ strains are two of the primary "genetic backgrounds" for modeling brain disease and testing therapeutic approaches. However, extensive literature describes basal differences in the behavioral, neuroanatomical and neurochemical profiles of the two strains, which raises questions on whether the observed effects are pathology specific or depend on the genetic background of each strain. Here, we performed a systematic comparative exploration of brain structure and function of C57BL/6 and BALB/cJ mice using Magnetic Resonance Imaging (MRI). We combined deformation-based morphometry (DBM), diffusion MRI and high-resolution fiber mapping (hrFM) along with resting-state functional MRI (rs-fMRI) and demonstrated brain-wide differences in the morphology and "connectome" features of the two strains. Essential inter-strain differences were depicted regarding the size and the fiber density (FD) within frontal cortices, along cortico-striatal, thalamic and midbrain pathways as well as genu and splenium of corpus callosum. Structural dissimilarities were accompanied by specific FC patterns, emphasizing strain differences in frontal and basal forebrain functional networks as well as hubness characteristics. Rs-fMRI data further indicated differences of reward-aversion circuitry and default mode network (DMN) patterns. The inter-hemispherical FC showed flexibility and strain-specific adjustment of their patterns in agreement with the structural characteristics.
Collapse
|
11
|
Zhang T, Jiang Q, Xu F, Zhang R, Liu D, Guo D, Wu J, Wen Y, Wang X, Jiang W, Bi H. Alternation of Resting-State Functional Connectivity Between Visual Cortex and Hypothalamus in Guinea Pigs With Experimental Glucocorticoid Enhanced Myopia After the Treatment of Electroacupuncture. Front Neuroinform 2021; 14:579769. [PMID: 33519409 PMCID: PMC7838498 DOI: 10.3389/fninf.2020.579769] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 12/07/2020] [Indexed: 12/12/2022] Open
Abstract
Excessive glucocorticoids (GC) may lead to the aggravation of several basic diseases including myopia, due to plasma hormone imbalances associated with the hypothalamic–pituitary–adrenal axis (HPAA). Electroacupuncture (EA) is an effective therapeutic method to treat many diseases, although it remains unclear whether EA at acupoints on the foot or back would be effective in treating eye diseases. It was recently found that visual cortex activity for responses to visual stimuli with spatial frequency and resting-state functional connectivity (FC) between the supramarginal gyrus and rostrolateral prefrontal cortex was significantly reduced in patients with high myopia. The present study aims to investigate the role of the alternation of resting-state FC among the bilateral visual cortex and hypothalamus in exerting anti-myopia effects of EA in GC-enhanced lens-induced myopic (LIM) guinea pigs such that the mechanisms of EA to treat GC-enhanced myopia at Shenshu (BL23) acupoints can be probed. To confirm the effects of EA, ocular parameters including axial length and GC-associated physiological parameters such as animal appearance, behavior, bodyweight, and levels of four HPAA-associated plasma hormones [free triiodothyronine (FT3), free thyroxine (FT4), estradiol (E2), and testosterone (T)] were also collected. Increased resting-state FC between the left and right visual cortex was detected in GC-enhanced lens-induced myopic guinea pigs with EA at BL23 acupoints (LIM+GC+EA) guinea pigs compared to GC-enhanced lens-induced myopic guinea pigs with EA at sham acupoints (LIM+GC+Sham) guinea pigs, as well as suppressed myopia and recovery of symptoms initially caused by overdose of GC. Recovered symptoms included improved animal appearance, behavior, bodyweight, and HPAA-associated plasma hormone levels were observed after 4 weeks of EA treatment. In contrast, the LIM+GC+Sham group showed decreased FC with elongation of axial length for myopization as compared to the control group and LIM group and exhibited a deterioration in physiological parameters including reduced body weight and balance disruption in the four measured HPAA-associated plasma hormones. Our findings suggest that EA could effectively treat GC-enhanced myopia by increasing resting-state FC between the left and right visual cortices, which may be pivotal to further understanding the application and mechanisms of EA in treating GC-enhanced myopia.
Collapse
Affiliation(s)
- Tao Zhang
- The First College of Clinical Medicine, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Qian Jiang
- Department of Ophthalmology and Optometry, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Furu Xu
- Department of Ophthalmology and Optometry, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Ruixue Zhang
- Department of Ophthalmology and Optometry, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Dezheng Liu
- Department of Ophthalmology and Optometry, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Dadong Guo
- Shandong Province Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Therapy of Ocular Disease, Eye Institute of Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Jianfeng Wu
- Department of Ophthalmology and Optometry, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Ying Wen
- Affiliated Eye Hospital of Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Xingrong Wang
- Affiliated Eye Hospital of Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Wenjun Jiang
- Shandong Province Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Therapy of Ocular Disease, Eye Institute of Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Hongsheng Bi
- Shandong Province Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Therapy of Ocular Disease, Eye Institute of Shandong University of Traditional Chinese Medicine, Jinan, China
| |
Collapse
|
12
|
Thalamic low frequency activity facilitates resting-state cortical interhemispheric MRI functional connectivity. Neuroimage 2019; 201:115985. [DOI: 10.1016/j.neuroimage.2019.06.063] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 06/18/2019] [Accepted: 06/26/2019] [Indexed: 12/20/2022] Open
|
13
|
Mancuso L, Uddin LQ, Nani A, Costa T, Cauda F. Brain functional connectivity in individuals with callosotomy and agenesis of the corpus callosum: A systematic review. Neurosci Biobehav Rev 2019; 105:231-248. [DOI: 10.1016/j.neubiorev.2019.07.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2018] [Revised: 06/30/2019] [Accepted: 07/04/2019] [Indexed: 02/05/2023]
|
14
|
Manno FAM, Isla AG, Manno SHC, Ahmed I, Cheng SH, Barrios FA, Lau C. Early Stage Alterations in White Matter and Decreased Functional Interhemispheric Hippocampal Connectivity in the 3xTg Mouse Model of Alzheimer's Disease. Front Aging Neurosci 2019; 11:39. [PMID: 30967770 PMCID: PMC6440287 DOI: 10.3389/fnagi.2019.00039] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 02/08/2019] [Indexed: 12/21/2022] Open
Abstract
Alzheimer’s disease (AD) is characterized in the late stages by amyloid-β (Aβ) plaques and neurofibrillary tangles. Nevertheless, recent evidence has indicated that early changes in cerebral connectivity could compromise cognitive functions even before the appearance of the classical neuropathological features. Diffusion tensor imaging (DTI), resting-state functional magnetic resonance imaging (rs-fMRI) and volumetry were performed in the triple transgenic mouse model of AD (3xTg-AD) at 2 months of age, prior to the development of intraneuronal plaque accumulation. We found the 3xTg-AD had significant fractional anisotropy (FA) increase and radial diffusivity (RD) decrease in the cortex compared with wild-type controls, while axial diffusivity (AD) and mean diffusivity (MD) were similar. Interhemispheric hippocampal connectivity was decreased in the 3xTg-AD while connectivity in the caudate putamen (CPu) was similar to controls. Most surprising, ventricular volume in the 3xTg-AD was four times larger than controls. The results obtained in this study characterize the early stage changes in interhemispheric hippocampal connectivity in the 3xTg-AD mouse that could represent a translational biomarker to human models in preclinical stages of the AD.
Collapse
Affiliation(s)
- Francis A M Manno
- Department of Physics, City University of Hong Kong, Kowloon, Hong Kong.,Instituto de Neurobiología, Universidad Nacional Autónoma de México, Juriquilla, Mexico
| | - Arturo G Isla
- Neuronal Oscillations Laboratory, Department of Neurobiology, Care Sciences and Society, Division of Neurogeriatrics, Karolinska Institutet, Stockholm, Sweden
| | - Sinai H C Manno
- Department of Physics, City University of Hong Kong, Kowloon, Hong Kong.,State Key Laboratory of Marine Pollution (SKLMP), City University of Hong Kong, Kowloon, Hong Kong.,Department of Biomedical Sciences, College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong
| | - Irfan Ahmed
- Department of Physics, City University of Hong Kong, Kowloon, Hong Kong.,Electrical Engineering Department, Sukkur IBA University, Sukkur, Pakistan
| | - Shuk Han Cheng
- State Key Laboratory of Marine Pollution (SKLMP), City University of Hong Kong, Kowloon, Hong Kong.,Department of Biomedical Sciences, College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong.,Department of Materials Science and Engineering, City University of Hong Kong, Kowloon, Hong Kong
| | - Fernando A Barrios
- Instituto de Neurobiología, Universidad Nacional Autónoma de México, Juriquilla, Mexico
| | - Condon Lau
- Department of Physics, City University of Hong Kong, Kowloon, Hong Kong
| |
Collapse
|
15
|
Zhu X, Suk HI, Lee SW, Shen D. Discriminative self-representation sparse regression for neuroimaging-based alzheimer's disease diagnosis. Brain Imaging Behav 2019; 13:27-40. [PMID: 28624881 PMCID: PMC5811409 DOI: 10.1007/s11682-017-9731-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
In this paper, we propose a novel feature selection method by jointly considering (1) 'task-specific' relations between response variables (e.g., clinical labels in this work) and neuroimaging features and (2) 'self-representation' relations among neuroimaging features in a sparse regression framework. Specifically, the task-specific relation is devised to learn the relative importance of features for representation of response variables by a linear combination of the input features in a supervised manner, while the self-representation relation is used to take into account the inherent information among neuroimaging features such that any feature can be represented by a weighted sum of the other features, regardless of the label information, in an unsupervised manner. By integrating these two different relations along with a group sparsity constraint, we formulate a new sparse linear regression model for class-discriminative feature selection. The selected features are used to train a support vector machine for classification. To validate the effectiveness of the proposed method, we conducted experiments on the Alzheimer's Disease Neuroimaging Initiative (ADNI) dataset; experimental results showed superiority of the proposed method over the state-of-the-art methods considered in this work.
Collapse
Affiliation(s)
- Xiaofeng Zhu
- Department of Radiology and BRIC, The University of North Carolina at Chapel Hill, Chapel Hill, USA
| | - Heung-Il Suk
- Department of Brain and Cognitive Engineering, Korea University, Seoul, Republic of Korea
| | - Seong-Whan Lee
- Department of Brain and Cognitive Engineering, Korea University, Seoul, Republic of Korea
| | - Dinggang Shen
- Department of Radiology and BRIC, The University of North Carolina at Chapel Hill, Chapel Hill, USA.
- Department of Brain and Cognitive Engineering, Korea University, Seoul, Republic of Korea.
| |
Collapse
|
16
|
Huang P, Gao T, Dong Z, Zhou C, Lai Y, Pan T, Liu Y, Zhao X, Sun X, Hua H, Wen G, Gao L, Lv Z. Neural circuitry among connecting the hippocampus, prefrontal cortex and basolateral amygdala in a mouse depression model: Associations correlations between BDNF levels and BOLD – fMRI signals. Brain Res Bull 2018; 142:107-115. [DOI: 10.1016/j.brainresbull.2018.06.019] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 06/21/2018] [Accepted: 06/28/2018] [Indexed: 01/16/2023]
|
17
|
Casimo K, Grassia F, Poliachik SL, Novotny E, Poliakov A, Ojemann JG. Preservation of electrophysiological functional connectivity after partial corpus callosotomy: case report. J Neurosurg Pediatr 2018; 22:214-219. [PMID: 29775133 DOI: 10.3171/2018.2.peds17549] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Prior studies of functional connectivity following callosotomy have disagreed in the observed effects on interhemispheric functional connectivity. These connectivity studies, in multiple electrophysiological methods and functional MRI, have found conflicting reductions in connectivity or patterns resembling typical individuals. The authors examined a case of partial anterior corpus callosum connection, where pairs of bilateral electrocorticographic electrodes had been placed over homologous regions in the left and right hemispheres. They sorted electrode pairs by whether their direct corpus callosum connection had been disconnected or preserved using diffusion tensor imaging and native anatomical MRI, and they estimated functional connectivity between pairs of electrodes over homologous regions using phase-locking value. They found no significant differences in any frequency band between pairs of electrodes that had their corpus callosum connection disconnected and those that had an intact connection. The authors' results may imply that the corpus callosum is not an obligatory mediator of connectivity between homologous sites in opposite hemispheres. This interhemispheric synchronization may also be linked to disruption of seizure activity.
Collapse
Affiliation(s)
- Kaitlyn Casimo
- 1Graduate Program in Neuroscience and.,2Center for Sensorimotor Neural Engineering, University of Washington, Seattle, Washington
| | - Fabio Grassia
- 3Department of Neurosurgery, University of Milan, San Gerardo Hospital, Monza, Italy; and
| | - Sandra L Poliachik
- 3Department of Neurosurgery, University of Milan, San Gerardo Hospital, Monza, Italy; and.,5Center for Clinical and Translational Research
| | - Edward Novotny
- 6Department of Neurology.,7Center for Integrated Brain Research, and
| | - Andrew Poliakov
- 3Department of Neurosurgery, University of Milan, San Gerardo Hospital, Monza, Italy; and.,4Department of Radiology
| | - Jeffrey G Ojemann
- 1Graduate Program in Neuroscience and.,2Center for Sensorimotor Neural Engineering, University of Washington, Seattle, Washington.,8Department of Neurosurgery, Seattle Children's Hospital, Seattle, Washington
| |
Collapse
|
18
|
Leong ATL, Dong CM, Gao PP, Chan RW, To A, Sanes DH, Wu EX. Optogenetic auditory fMRI reveals the effects of visual cortical inputs on auditory midbrain response. Sci Rep 2018; 8:8736. [PMID: 29880842 PMCID: PMC5992211 DOI: 10.1038/s41598-018-26568-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 05/10/2018] [Indexed: 12/20/2022] Open
Abstract
Sensory cortices contain extensive descending (corticofugal) pathways, yet their impact on brainstem processing - particularly across sensory systems - remains poorly understood. In the auditory system, the inferior colliculus (IC) in the midbrain receives cross-modal inputs from the visual cortex (VC). However, the influences from VC on auditory midbrain processing are unclear. To investigate whether and how visual cortical inputs affect IC auditory responses, the present study combines auditory blood-oxygenation-level-dependent (BOLD) functional MRI (fMRI) with cell-type specific optogenetic manipulation of visual cortex. The results show that predominant optogenetic excitation of the excitatory pyramidal neurons in the infragranular layers of the primary VC enhances the noise-evoked BOLD fMRI responses within the IC. This finding reveals that inputs from VC influence and facilitate basic sound processing in the auditory midbrain. Such combined optogenetic and auditory fMRI approach can shed light on the large-scale modulatory effects of corticofugal pathways and guide detailed electrophysiological studies in the future.
Collapse
Affiliation(s)
- Alex T L Leong
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.,Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Celia M Dong
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.,Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Patrick P Gao
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.,Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Russell W Chan
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.,Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Anthea To
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.,Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Dan H Sanes
- Center for Neural Science, New York University, New York, NY, 10003, United States
| | - Ed X Wu
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China. .,Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China. .,School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China. .,Department of Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
| |
Collapse
|
19
|
Lam CLM, Yiend J, Lee TMC. Imaging and neuropsychological correlates of white matter lesions in different subtypes of Mild Cognitive Impairment: A systematic review. NeuroRehabilitation 2018; 41:189-204. [PMID: 28527230 DOI: 10.3233/nre-171471] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND White matter lesions (WML) are prevalent in older adults. The association between WML and cognition in different subtypes of Mild Cognitive Impairment (MCI) is inconsistent in the literature. OBJECTVES We aim to provide a systematic review on the impact of WML in different subtypes of MCI, and discuss the recent findings on white matter plasticity. METHODS We reviewed peer-reviewed articles from January 2011 to August 2016 and identified 12 studies investigating the association between WML and subtypes of MCI with both neuroimaging and cognitive measures. RESULTS Our review shows that 1) WM abnormality was identified between different subtypes of MCI and healthy controls on diffusion imaging; 2) neither visual ratings of WML nor its volumetry differentiate different subtypes of MCI or its prognosis to dementia; and 3) cognitive correlates of WML were evident in the Amnestic-type MCI in the domains of memory, language, psychomotor speed, attention and executive functions. CONCLUSION Cognitive reserve and the plasticity of white matter may modulate the impact of WML on the manifestation of the neurodegenerative disease. Further research is needed to study the plasticity of white matter in the MCI population to evaluate its potential clinical application.
Collapse
Affiliation(s)
- Charlene L M Lam
- Laboratory of Neuropsychology, The University of Hong Kong, Hong Kong.,Institute of Clinical Neuropsychology, The University of Hong Kong, Hong Kong
| | - Jenny Yiend
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, UK
| | - Tatia M C Lee
- Laboratory of Neuropsychology, The University of Hong Kong, Hong Kong.,Institute of Clinical Neuropsychology, The University of Hong Kong, Hong Kong.,The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong
| |
Collapse
|
20
|
Cochereau J, Deverdun J, Herbet G, Charroud C, Boyer A, Moritz-Gasser S, Le Bars E, Molino F, Bonafé A, Menjot de Champfleur N, Duffau H. Comparison between resting state fMRI networks and responsive cortical stimulations in glioma patients. Hum Brain Mapp 2018; 37:3721-3732. [PMID: 27246771 DOI: 10.1002/hbm.23270] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2015] [Revised: 05/01/2016] [Accepted: 05/17/2016] [Indexed: 12/26/2022] Open
Abstract
OBJECTIVES To validate the functional relevance of resting state networks (RSNs) by means of a comparison of resting state connectivity (RSC) between language regions elicited by direct cortical stimulation versus RSC between random regions; and to evaluate the accuracy of resting state fMRI in surgical planning by assessing the overlap between RSNs and intraoperative functional mapping results. METHODS Sensorimotor and language eloquent sites were identified by direct electrical cortical stimulation in 98 patients with a diffuse low-grade glioma. A seed to voxel analysis with inter-language stimulation point connectivity versus inter-random ROIs connectivity was performed (19 patients). An independant component analysis (ICA) was also applied to rsfMRI data. Language and sensorimotor components were selected over 20 independent components and compared to the corresponding stimulation points and resected cortex masks (31 and 90 patients, respectively). RESULTS Mean connectivity value between language seeds was significantly higher than the one between random seeds (0.68 ± 0.39 and 0.12 ± 0.21 respectively, P < 10-10 ). 96 ± 11% of sensorimotor stimulation points were located within 10 mm from sensorimotor ICA maps versus 92 ± 21% for language. 3.1 and 15% of resected cortex overlapped sensorimotor and language networks, respectively. Mean sensorimotor stimulation points and resected cortex z-scores were 2.0 ± 1.2 and -0.050 ± 0.60, respectively (P < 10-10 ). Mean language stimulation points and resected cortex z-scores were 1.6 ± 1.9 and 0.68 ± 0.91, respectively, P < 0.005. CONCLUSION The significantly higher RSC between language seeds than between random seeds validated the functional relevance of RSC. ICA partly succeeded to distinguish eloquent versus surgically removable areas and may be possibly used as a complementary tool to intraoperative mapping. Hum Brain Mapp 37:3721-3732, 2016. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Jérôme Cochereau
- Department of Neurosurgery, Montpellier University Hospital Center, Gui de Chauliac Hospital, Montpellier, France.,Unité I2FH, Institut d'Imagerie Fonctionnelle Humaine, Montpellier University Hospital Center, Gui de Chauliac Hospital, Montpellier, France.,Team "Plasticity of Central Nervous System, Stem Cells and Glial Tumors", INSERM U1051, Institute of Neurosciences of Montpellier, Montpellier, France.,Department of Neuroradiology, Montpellier University Hospital Center, Gui de Chauliac Hospital, Montpellier, France
| | - Jérémy Deverdun
- Unité I2FH, Institut d'Imagerie Fonctionnelle Humaine, Montpellier University Hospital Center, Gui de Chauliac Hospital, Montpellier, France.,Department of Neuroradiology, Montpellier University Hospital Center, Gui de Chauliac Hospital, Montpellier, France.,Institut de Génomique Fonctionnelle, Unité UMR 5203 - INSERM U661 - Université Montpellier II - Université Montpellier I, France.,Laboratoire Charles Coulomb, Unité CNRS UMR 5221 - Université Montpellier II, Montpellier, France
| | - Guillaume Herbet
- Department of Neurosurgery, Montpellier University Hospital Center, Gui de Chauliac Hospital, Montpellier, France.,Team "Plasticity of Central Nervous System, Stem Cells and Glial Tumors", INSERM U1051, Institute of Neurosciences of Montpellier, Montpellier, France
| | - Céline Charroud
- Unité I2FH, Institut d'Imagerie Fonctionnelle Humaine, Montpellier University Hospital Center, Gui de Chauliac Hospital, Montpellier, France.,Department of Neuroradiology, Montpellier University Hospital Center, Gui de Chauliac Hospital, Montpellier, France
| | - Anthony Boyer
- Unité I2FH, Institut d'Imagerie Fonctionnelle Humaine, Montpellier University Hospital Center, Gui de Chauliac Hospital, Montpellier, France.,University of Montpellier 2, LIRMM laboratory, DEMAR Team, CNRS, INRIA, Montpellier, 34095, France
| | - Sylvie Moritz-Gasser
- Department of Neurosurgery, Montpellier University Hospital Center, Gui de Chauliac Hospital, Montpellier, France.,Team "Plasticity of Central Nervous System, Stem Cells and Glial Tumors", INSERM U1051, Institute of Neurosciences of Montpellier, Montpellier, France
| | - Emmanuelle Le Bars
- Unité I2FH, Institut d'Imagerie Fonctionnelle Humaine, Montpellier University Hospital Center, Gui de Chauliac Hospital, Montpellier, France.,Department of Neuroradiology, Montpellier University Hospital Center, Gui de Chauliac Hospital, Montpellier, France.,Laboratoire Charles Coulomb, Unité CNRS UMR 5221 - Université Montpellier II, Montpellier, France
| | - François Molino
- Institut de Génomique Fonctionnelle, Unité UMR 5203 - INSERM U661 - Université Montpellier II - Université Montpellier I, France.,Laboratoire Charles Coulomb, Unité CNRS UMR 5221 - Université Montpellier II, Montpellier, France
| | - Alain Bonafé
- Unité I2FH, Institut d'Imagerie Fonctionnelle Humaine, Montpellier University Hospital Center, Gui de Chauliac Hospital, Montpellier, France.,Team "Plasticity of Central Nervous System, Stem Cells and Glial Tumors", INSERM U1051, Institute of Neurosciences of Montpellier, Montpellier, France.,Department of Neuroradiology, Montpellier University Hospital Center, Gui de Chauliac Hospital, Montpellier, France
| | - Nicolas Menjot de Champfleur
- Unité I2FH, Institut d'Imagerie Fonctionnelle Humaine, Montpellier University Hospital Center, Gui de Chauliac Hospital, Montpellier, France.,Team "Plasticity of Central Nervous System, Stem Cells and Glial Tumors", INSERM U1051, Institute of Neurosciences of Montpellier, Montpellier, France.,Department of Neuroradiology, Montpellier University Hospital Center, Gui de Chauliac Hospital, Montpellier, France.,Laboratoire Charles Coulomb, Unité CNRS UMR 5221 - Université Montpellier II, Montpellier, France
| | - Hugues Duffau
- Department of Neurosurgery, Montpellier University Hospital Center, Gui de Chauliac Hospital, Montpellier, France.,Team "Plasticity of Central Nervous System, Stem Cells and Glial Tumors", INSERM U1051, Institute of Neurosciences of Montpellier, Montpellier, France
| |
Collapse
|
21
|
Functional networks and network perturbations in rodents. Neuroimage 2017; 163:419-436. [DOI: 10.1016/j.neuroimage.2017.09.038] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 09/15/2017] [Accepted: 09/19/2017] [Indexed: 11/16/2022] Open
|
22
|
Low-frequency hippocampal-cortical activity drives brain-wide resting-state functional MRI connectivity. Proc Natl Acad Sci U S A 2017; 114:E6972-E6981. [PMID: 28760982 DOI: 10.1073/pnas.1703309114] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The hippocampus, including the dorsal dentate gyrus (dDG), and cortex engage in bidirectional communication. We propose that low-frequency activity in hippocampal-cortical pathways contributes to brain-wide resting-state connectivity to integrate sensory information. Using optogenetic stimulation and brain-wide fMRI and resting-state fMRI (rsfMRI), we determined the large-scale effects of spatiotemporal-specific downstream propagation of hippocampal activity. Low-frequency (1 Hz), but not high-frequency (40 Hz), stimulation of dDG excitatory neurons evoked robust cortical and subcortical brain-wide fMRI responses. More importantly, it enhanced interhemispheric rsfMRI connectivity in various cortices and hippocampus. Subsequent local field potential recordings revealed an increase in slow oscillations in dorsal hippocampus and visual cortex, interhemispheric visual cortical connectivity, and hippocampal-cortical connectivity. Meanwhile, pharmacological inactivation of dDG neurons decreased interhemispheric rsfMRI connectivity. Functionally, visually evoked fMRI responses in visual regions also increased during and after low-frequency dDG stimulation. Together, our results indicate that low-frequency activity robustly propagates in the dorsal hippocampal-cortical pathway, drives interhemispheric cortical rsfMRI connectivity, and mediates visual processing.
Collapse
|
23
|
Wiesmann M, Roelofs M, van der Lugt R, Heerschap A, Kiliaan AJ, Claassen JAHR. Angiotensin II, hypertension and angiotensin II receptor antagonism: Roles in the behavioural and brain pathology of a mouse model of Alzheimer's disease. J Cereb Blood Flow Metab 2017; 37:2396-2413. [PMID: 27596834 PMCID: PMC5531339 DOI: 10.1177/0271678x16667364] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 07/26/2016] [Accepted: 08/08/2016] [Indexed: 12/11/2022]
Abstract
Elevated angiotensin II causes hypertension and contributes to Alzheimer's disease by affecting cerebral blood flow. Angiotensin II receptor blockers may provide candidates to reduce (vascular) risk factors for Alzheimer's disease. We studied effects of two months of angiotensin II-induced hypertension on systolic blood pressure, and treatment with the angiotensin II receptor blockers, eprosartan mesylate, after one month of induced hypertension in wild-type C57bl/6j and AβPPswe/PS1ΔE9 (AβPP/PS1/Alzheimer's disease) mice. AβPP/PS1 showed higher systolic blood pressure than wild-type. Subsequent eprosartan mesylate treatment restored this elevated systolic blood pressure in all mice. Functional connectivity was decreased in angiotensin II-infused Alzheimer's disease and wild-type mice, and only 12 months of Alzheimer's disease mice showed impaired cerebral blood flow. Only angiotensin II-infused Alzheimer's disease mice exhibited decreased spatial learning in the Morris water maze. Altogether, angiotensin II-induced hypertension not only exacerbated Alzheimer's disease-like pathological changes such as impairment of cerebral blood flow, functional connectivity, and cognition only in Alzheimer's disease model mice, but it also induced decreased functional connectivity in wild-type mice. However, we could not detect hypertension-induced overexpression of Aβ nor increased neuroinflammation. Our findings suggest a link between midlife hypertension, decreased cerebral hemodynamics and connectivity in an Alzheimer's disease mouse model. Eprosartan mesylate treatment restored and beneficially affected cerebral blood flow and connectivity. This model could be used to investigate prevention/treatment strategies in early Alzheimer's disease.
Collapse
Affiliation(s)
- Maximilian Wiesmann
- Department of Anatomy, Radboud Alzheimer Center, Donders Institute for Brain, Cognition & Behaviour, Radboud university medical center, Nijmegen, The Netherlands
- Department of Geriatric Medicine, Radboud Alzheimer Center, Donders Institute for Brain, Cognition & Behaviour, Radboud university medical center, Nijmegen, The Netherlands
| | - Monica Roelofs
- Department of Anatomy, Radboud Alzheimer Center, Donders Institute for Brain, Cognition & Behaviour, Radboud university medical center, Nijmegen, The Netherlands
| | - Robert van der Lugt
- Department of Anatomy, Radboud Alzheimer Center, Donders Institute for Brain, Cognition & Behaviour, Radboud university medical center, Nijmegen, The Netherlands
| | - Arend Heerschap
- Department of Radiology & Nuclear Medicine, Radboud university medical center, Nijmegen, The Netherlands
| | - Amanda J Kiliaan
- Department of Anatomy, Radboud Alzheimer Center, Donders Institute for Brain, Cognition & Behaviour, Radboud university medical center, Nijmegen, The Netherlands
| | - Jurgen AHR Claassen
- Department of Geriatric Medicine, Radboud Alzheimer Center, Donders Institute for Brain, Cognition & Behaviour, Radboud university medical center, Nijmegen, The Netherlands
| |
Collapse
|
24
|
Han K, Davis RA, Chapman SB, Krawczyk DC. Strategy-based reasoning training modulates cortical thickness and resting-state functional connectivity in adults with chronic traumatic brain injury. Brain Behav 2017; 7:e00687. [PMID: 28523229 PMCID: PMC5434192 DOI: 10.1002/brb3.687] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 02/13/2017] [Accepted: 02/26/2017] [Indexed: 12/31/2022] Open
Abstract
INTRODUCTION Prior studies have demonstrated training-induced changes in the healthy adult brain. Yet, it remains unclear how the injured brain responds to cognitive training months-to-years after injury. METHODS Sixty individuals with chronic traumatic brain injury (TBI) were randomized into either strategy-based (N = 31) or knowledge-based (N = 29) training for 8 weeks. We measured cortical thickness and resting-state functional connectivity (rsFC) before training, immediately posttraining, and 3 months posttraining. RESULTS Relative to the knowledge-based training group, the cortical thickness of the strategy-based training group showed diverse temporal patterns of changes over multiple brain regions (pvertex < .05, pcluster < .05): (1) increases followed by decreases, (2) monotonic increases, and (3) monotonic decreases. However, network-based statistics (NBS) analysis of rsFC among these regions revealed that the strategy-based training group induced only monotonic increases in connectivity, relative to the knowledge-based training group (|Z| > 1.96, pNBS < 0.05). Complementing the rsFC results, the strategy-based training group yielded monotonic improvement in scores for the trail-making test (p < .05). Analyses of brain-behavior relationships revealed that improvement in trail-making scores were associated with training-induced changes in cortical thickness (pvertex < .05, pcluster < .05) and rsFC (pvertex < .05, pcluster < .005) within the strategy-based training group. CONCLUSIONS These findings suggest that training-induced brain plasticity continues through chronic phases of TBI and that brain connectivity and cortical thickness may serve as markers of plasticity.
Collapse
Affiliation(s)
- Kihwan Han
- Center for BrainHealthSchool of Behavioral and Brain SciencesThe University of Texas at DallasDallasTXUSA
| | - Rebecca A. Davis
- Center for BrainHealthSchool of Behavioral and Brain SciencesThe University of Texas at DallasDallasTXUSA
| | - Sandra B. Chapman
- Center for BrainHealthSchool of Behavioral and Brain SciencesThe University of Texas at DallasDallasTXUSA
| | - Daniel C. Krawczyk
- Center for BrainHealthSchool of Behavioral and Brain SciencesThe University of Texas at DallasDallasTXUSA
- Department of PsychiatryUniversity of Texas Southwestern Medical CenterDallasTXUSA
| |
Collapse
|
25
|
Wiesmann M, Zerbi V, Jansen D, Lütjohann D, Veltien A, Heerschap A, Kiliaan AJ. Hypertension, cerebrovascular impairment, and cognitive decline in aged AβPP/PS1 mice. Theranostics 2017; 7:1277-1289. [PMID: 28435465 PMCID: PMC5399593 DOI: 10.7150/thno.18509] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2016] [Accepted: 01/18/2017] [Indexed: 11/05/2022] Open
Abstract
Cardiovascular risk factors, especially hypertension, are also major risk factors for Alzheimer's disease (AD). To elucidate the underlying vascular origin of neurodegenerative processes in AD, we investigated the relation between systolic blood pressure (SBP) cerebral blood flow (CBF) and vasoreactivity with brain structure and function in a 16-18 months old double transgenic AβPPswe/PS1dE9 (AβPP/PS1) mouse model for AD. These aging AβPP/PS1 mice showed an increased SBP linked to a declined regional CBF. Furthermore, using advanced MRI techniques, decline of functional and structural connectivity was revealed in the AD-like mice coupled to impaired cognition, increased locomotor activity, and anxiety-related behavior. Post mortem analyses demonstrated also increased neuroinflammation, and both decreased synaptogenesis and neurogenesis in the AβPP/PS1 mice. Additionally, deviant levels of fatty acids and sterols were present in the brain tissue of the AβPP/PS1 mice indicating maladapted brain fatty acid metabolism. Our findings suggest a link between increased SBP, decreased cerebral hemodynamics and connectivity in an AD mouse model during aging, leading to behavioral and cognitive impairments. As these results mirror the complex clinical symptomatology in the prodromal phase of AD, we suggest that this AD-like murine model could be used to investigate prevention and treatment strategies for early AD patients. Moreover, this study helps to develop more efficient therapies and diagnostics for this very early stage of AD.
Collapse
|
26
|
Chen H, Mo S. Regional Homogeneity Changes in Nicotine Addicts by Resting-State fMRI. PLoS One 2017; 12:e0170143. [PMID: 28081226 PMCID: PMC5231336 DOI: 10.1371/journal.pone.0170143] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 12/29/2016] [Indexed: 11/29/2022] Open
Abstract
Objective To reveal the brain functional changes of nicotine addicts compared with those of non-smokers and explore the objective biomarker for nicotine dependence evaluation. Methods A total of 14 smokers and 11 non-smoking controls were recruited for this study. Resting-state functional magnetic resonance imaging and regional homogeneity (ReHo) were applied in the neural activity analysis. Two-sample t-test was performed to examine the voxel-wise difference between the smokers and the controls. Correlation analysis between the ReHo values and the Fagerstrom Test for Nicotine Dependence (FTND) scores were performed to explore the biomarkers for the clinical characteristics of smokers. Results The ReHo values from the right superior frontal gyrus of the Brodmann’s area (BA) 9 to the right middle frontal gyrus and the ReHo value from the left and right precuneus (BA 23) to the left and right middle cingulum gyrus were lower in the smokers than in the non-smokers. The ReHo value in the precuneus (BA 23) was significantly and positively correlated with the FTND score of smokers. Conclusion The ReHo values in the right superior frontal gyrus and left precuneus can be used to separate the smokers from the non-smokers. In particular, the left precuneus is a potential neuroimaging biomarker for nicotine addicts.
Collapse
Affiliation(s)
- Hongbo Chen
- School of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin, Guangxi, China
- * E-mail: (HC); (SM)
| | - Shaofeng Mo
- School of Geosci and Info-physics, Central South University, Changsha, Hunan, China
- * E-mail: (HC); (SM)
| |
Collapse
|
27
|
Long-range projections coordinate distributed brain-wide neural activity with a specific spatiotemporal profile. Proc Natl Acad Sci U S A 2016; 113:E8306-E8315. [PMID: 27930323 DOI: 10.1073/pnas.1616361113] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
One challenge in contemporary neuroscience is to achieve an integrated understanding of the large-scale brain-wide interactions, particularly the spatiotemporal patterns of neural activity that give rise to functions and behavior. At present, little is known about the spatiotemporal properties of long-range neuronal networks. We examined brain-wide neural activity patterns elicited by stimulating ventral posteromedial (VPM) thalamo-cortical excitatory neurons through combined optogenetic stimulation and functional MRI (fMRI). We detected robust optogenetically evoked fMRI activation bilaterally in primary visual, somatosensory, and auditory cortices at low (1 Hz) but not high frequencies (5-40 Hz). Subsequent electrophysiological recordings indicated interactions over long temporal windows across thalamo-cortical, cortico-cortical, and interhemispheric callosal projections at low frequencies. We further observed enhanced visually evoked fMRI activation during and after VPM stimulation in the superior colliculus, indicating that visual processing was subcortically modulated by low-frequency activity originating from VPM. Stimulating posteromedial complex thalamo-cortical excitatory neurons also evoked brain-wide blood-oxygenation-level-dependent activation, although with a distinct spatiotemporal profile. Our results directly demonstrate that low-frequency activity governs large-scale, brain-wide connectivity and interactions through long-range excitatory projections to coordinate the functional integration of remote brain regions. This low-frequency phenomenon contributes to the neural basis of long-range functional connectivity as measured by resting-state fMRI.
Collapse
|
28
|
Mitaki S, Onoda K, Abe S, Oguro H, Yamaguchi S. The Effectiveness of Repetitive Transcranial Magnetic Stimulation for Poststroke Apathy Is Associated with Improved Interhemispheric Functional Connectivity. J Stroke Cerebrovasc Dis 2016; 25:e219-e221. [DOI: 10.1016/j.jstrokecerebrovasdis.2016.05.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 05/06/2016] [Accepted: 05/15/2016] [Indexed: 11/29/2022] Open
|
29
|
Awake whole-brain functional connectivity alterations in the adolescent spontaneously hypertensive rat feature visual streams and striatal networks. Brain Struct Funct 2016; 222:1673-1683. [DOI: 10.1007/s00429-016-1301-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 09/01/2016] [Indexed: 01/08/2023]
|
30
|
Elmer GI, Brown PL, Shepard PD. Engaging Research Domain Criteria (RDoC): Neurocircuitry in Search of Meaning. Schizophr Bull 2016; 42:1090-5. [PMID: 27412648 PMCID: PMC4988756 DOI: 10.1093/schbul/sbw096] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The Research Domain Criteria (RDoC) initiative was implemented to reorient the approach to mental health research from one focused on Diagnostic and Statistical Manual of Mental Disorders (DSM) nosology to one oriented to psychological constructs constrained by neurocircuitry and molecular entities. The initiative has generated significant discussion and valuable reflection on the moorings of psychiatric research. The purpose of this article is to illustrate how a basic or clinical investigator can engage RDoC to explore the neurobiological underpinnings of psychopathology and how a research question can be formulated in RDoC's framework. We utilize a brain region with significant growing interest, the habenula, as an example for probing RDoC's utility. Opportunities to enhance neurocircuitry-psychological construct associations and problems associated with neuronal populations that enable bidirectional circuitry influence are discussed. The exercise reveals areas for further development that could move RDoC from a promising research idea to a successfully engaged foundation for catalyzing clinically relevant discoveries.
Collapse
Affiliation(s)
- Greg I. Elmer
- *To whom correspondence should be addressed; MPRC, PO Box 21247, Maple and Locust Streets, Baltimore, MD 21228, USA; tel: 410-402-7576, fax: 410-402-6066, e-mail:
| | | | | |
Collapse
|
31
|
Neuroplasticity: Insights from Patients Harboring Gliomas. Neural Plast 2016; 2016:2365063. [PMID: 27478645 PMCID: PMC4949342 DOI: 10.1155/2016/2365063] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 06/08/2016] [Indexed: 12/16/2022] Open
Abstract
Neuroplasticity is the ability of the brain to reorganize itself during normal development and in response to illness. Recent advances in neuroimaging and direct cortical stimulation in human subjects have given neuroscientists a window into the timing and functional anatomy of brain networks underlying this dynamic process. This review will discuss the current knowledge about the mechanisms underlying neuroplasticity, with a particular emphasis on reorganization following CNS pathology. First, traditional mechanisms of neuroplasticity, most relevant to learning and memory, will be addressed, followed by a review of adaptive mechanisms in response to pathology, particularly the recruitment of perilesional cortical regions and unmasking of latent connections. Next, we discuss the utility and limitations of various investigative techniques, such as direct electrocortical stimulation (DES), functional magnetic resonance imaging (fMRI), corticocortical evoked potential (CCEP), and diffusion tensor imaging (DTI). Finally, the clinical utility of these results will be highlighted as well as possible future studies aimed at better understanding of the plastic potential of the brain with the ultimate goal of improving quality of life for patients with neurologic injury.
Collapse
|
32
|
Chen H, Wang L, King TZ, Mao H. Increased frontal functional networks in adult survivors of childhood brain tumors. NEUROIMAGE-CLINICAL 2016; 11:339-346. [PMID: 27298763 PMCID: PMC4893013 DOI: 10.1016/j.nicl.2016.02.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 02/13/2016] [Accepted: 02/18/2016] [Indexed: 12/20/2022]
Abstract
Childhood brain tumors and associated treatment have been shown to affect brain development and cognitive outcomes. Understanding the functional connectivity of brain many years after diagnosis and treatment may inform the development of interventions to improve the long-term outcomes of adult survivors of childhood brain tumors. This work investigated the frontal region functional connectivity of 16 adult survivors of childhood cerebellar tumors after an average of 14.9 years from diagnosis and 16 demographically-matched controls using resting state functional MRI (rs-fMRI). Independent component analysis (ICA) was applied to identify the resting state activity from rs-fMRI data and to select the specific regions associated with executive functions, followed by the secondary analysis of the functional networks connecting these regions. It was found that survivors exhibited differences in the functional connectivity in executive control network (ECN), default mode network (DMN) and salience network (SN) compared to demographically-matched controls. More specifically, the number of functional connectivity observed in the survivors is higher than that in the controls, and with increased strength, or stronger correlation coefficient between paired seeds, in survivors compared to the controls. Observed hyperconnectivity in the selected frontal functional network thus is consistent with findings in patients with other neurological injuries and diseases. rs-fMRI and ICA analysis were used to investigate functional connectivity of adult survivors of childhood brain tumors. Survivors exhibited changes in connectivity in executive function, default mode and salience networks compared to controls. Observed increased number and strength of functional connectivity suggest adaption of hyperconnectivity by survivors.
Collapse
Affiliation(s)
- Hongbo Chen
- Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA, USA; School of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin, Guangxi, China
| | - Liya Wang
- Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA, USA; Department of Radiology, The Cancer Hospital of Chinese Academy of Medical Sciences, Shenzhen, Guangdong, China
| | - Tricia Z King
- Department of Psychology and Neuroscience Institute, Georgia State University, Atlanta, GA, USA.
| | - Hui Mao
- Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA, USA.
| |
Collapse
|
33
|
Compensation through Functional Hyperconnectivity: A Longitudinal Connectome Assessment of Mild Traumatic Brain Injury. Neural Plast 2015; 2016:4072402. [PMID: 26819765 PMCID: PMC4706919 DOI: 10.1155/2016/4072402] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Revised: 08/07/2015] [Accepted: 08/11/2015] [Indexed: 11/18/2022] Open
Abstract
Mild traumatic brain injury (mTBI) is a major public health concern. Functional MRI has reported alterations in several brain networks following mTBI. However, the connectome-scale brain network changes are still unknown. In this study, sixteen mTBI patients were prospectively recruited from an emergency department and followed up at 4-6 weeks after injury. Twenty-four healthy controls were also scanned twice with the same time interval. Three hundred fifty-eight brain landmarks that preserve structural and functional correspondence of brain networks across individuals were used to investigate longitudinal brain connectivity. Network-based statistic (NBS) analysis did not find significant difference in the group-by-time interaction and time effects. However, 258 functional pairs show group differences in which mTBI patients have higher functional connectivity. Meta-analysis showed that "Action" and "Cognition" are the most affected functional domains. Categorization of connectomic signatures using multiview group-wise cluster analysis identified two patterns of functional hyperconnectivity among mTBI patients: (I) between the posterior cingulate cortex and the association areas of the brain and (II) between the occipital and the frontal lobes of the brain. Our results demonstrate that brain concussion renders connectome-scale brain network connectivity changes, and the brain tends to be hyperactivated to compensate the pathophysiological disturbances.
Collapse
|
34
|
Chan RW, Ho LC, Zhou IY, Gao PP, Chan KC, Wu EX. Structural and Functional Brain Remodeling during Pregnancy with Diffusion Tensor MRI and Resting-State Functional MRI. PLoS One 2015; 10:e0144328. [PMID: 26658306 PMCID: PMC4675543 DOI: 10.1371/journal.pone.0144328] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 11/17/2015] [Indexed: 01/25/2023] Open
Abstract
Although pregnancy-induced hormonal changes have been shown to alter the brain at the neuronal level, the exact effects of pregnancy on brain at the tissue level remain unclear. In this study, diffusion tensor imaging (DTI) and resting-state functional MRI (rsfMRI) were employed to investigate and document the effects of pregnancy on the structure and function of the brain tissues. Fifteen Sprague-Dawley female rats were longitudinally studied at three days before mating (baseline) and seventeen days after mating (G17). G17 is equivalent to the early stage of the third trimester in humans. Seven age-matched nulliparous female rats served as non-pregnant controls and were scanned at the same time-points. For DTI, diffusivity was found to generally increase in the whole brain during pregnancy, indicating structural changes at microscopic levels that facilitated water molecular movement. Regionally, mean diffusivity increased more pronouncedly in the dorsal hippocampus while fractional anisotropy in the dorsal dentate gyrus increased significantly during pregnancy. For rsfMRI, bilateral functional connectivity in the hippocampus increased significantly during pregnancy. Moreover, fractional anisotropy increase in the dentate gyrus appeared to correlate with the bilateral functional connectivity increase in the hippocampus. These findings revealed tissue structural modifications in the whole brain during pregnancy, and that the hippocampus was structurally and functionally remodeled in a more marked manner.
Collapse
Affiliation(s)
- Russell W. Chan
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Leon C. Ho
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Iris Y. Zhou
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Patrick P. Gao
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Kevin C. Chan
- UPMC Eye Center, Ophthalmology and Visual Science Research Center, Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Ed X. Wu
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- * E-mail:
| |
Collapse
|
35
|
Gao PP, Zhang JW, Fan SJ, Sanes DH, Wu EX. Auditory midbrain processing is differentially modulated by auditory and visual cortices: An auditory fMRI study. Neuroimage 2015; 123:22-32. [PMID: 26306991 DOI: 10.1016/j.neuroimage.2015.08.040] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Revised: 08/15/2015] [Accepted: 08/18/2015] [Indexed: 11/19/2022] Open
Abstract
The cortex contains extensive descending projections, yet the impact of cortical input on brainstem processing remains poorly understood. In the central auditory system, the auditory cortex contains direct and indirect pathways (via brainstem cholinergic cells) to nuclei of the auditory midbrain, called the inferior colliculus (IC). While these projections modulate auditory processing throughout the IC, single neuron recordings have samples from only a small fraction of cells during stimulation of the corticofugal pathway. Furthermore, assessments of cortical feedback have not been extended to sensory modalities other than audition. To address these issues, we devised blood-oxygen-level-dependent (BOLD) functional magnetic resonance imaging (fMRI) paradigms to measure the sound-evoked responses throughout the rat IC and investigated the effects of bilateral ablation of either auditory or visual cortices. Auditory cortex ablation increased the gain of IC responses to noise stimuli (primarily in the central nucleus of the IC) and decreased response selectivity to forward species-specific vocalizations (versus temporally reversed ones, most prominently in the external cortex of the IC). In contrast, visual cortex ablation decreased the gain and induced a much smaller effect on response selectivity. The results suggest that auditory cortical projections normally exert a large-scale and net suppressive influence on specific IC subnuclei, while visual cortical projections provide a facilitatory influence. Meanwhile, auditory cortical projections enhance the midbrain response selectivity to species-specific vocalizations. We also probed the role of the indirect cholinergic projections in the auditory system in the descending modulation process by pharmacologically blocking muscarinic cholinergic receptors. This manipulation did not affect the gain of IC responses but significantly reduced the response selectivity to vocalizations. The results imply that auditory cortical gain modulation is mediated primarily through direct projections and they point to future investigations of the differential roles of the direct and indirect projections in corticofugal modulation. In summary, our imaging findings demonstrate the large-scale descending influences, from both the auditory and visual cortices, on sound processing in different IC subdivisions. They can guide future studies on the coordinated activity across multiple regions of the auditory network, and its dysfunctions.
Collapse
Affiliation(s)
- Patrick P Gao
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Jevin W Zhang
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Shu-Juan Fan
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Dan H Sanes
- Center for Neural Science, New York University, New York, NY 10003, United States
| | - Ed X Wu
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; Department of Anatomy, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; Department of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
| |
Collapse
|
36
|
Gao PP, Zhang JW, Chan RW, Leong ATL, Wu EX. BOLD fMRI study of ultrahigh frequency encoding in the inferior colliculus. Neuroimage 2015; 114:427-37. [PMID: 25869860 DOI: 10.1016/j.neuroimage.2015.04.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 03/02/2015] [Accepted: 04/02/2015] [Indexed: 01/23/2023] Open
Abstract
Many vertebrates communicate with ultrahigh frequency (UHF) vocalizations to limit auditory detection by predators. The mechanisms underlying the neural encoding of such UHF sounds may provide important insights for understanding neural processing of other complex sounds (e.g. human speeches). In the auditory system, sound frequency is normally encoded topographically as tonotopy, which, however, contains very limited representation of UHFs in many species. Instead, electrophysiological studies suggested that two neural mechanisms, both exploiting the interactions between frequencies, may contribute to UHF processing. Neurons can exhibit excitatory or inhibitory responses to a tone when another UHF tone is presented simultaneously (combination sensitivity). They can also respond to such stimulation if they are tuned to the frequency of the cochlear-generated distortion products of the two tones, e.g. their difference frequency (cochlear distortion). Both mechanisms are present in an early station of the auditory pathway, the midbrain inferior colliculus (IC). Currently, it is unclear how prevalent the two mechanisms are and how they are functionally integrated in encoding UHFs. This study investigated these issues with large-view BOLD fMRI in rat auditory system, particularly the IC. UHF vocalizations (above 40kHz), but not pure tones at similar frequencies (45, 55, 65, 75kHz), evoked robust BOLD responses in multiple auditory nuclei, including the IC, reinforcing the sensitivity of the auditory system to UHFs despite limited representation in tonotopy. Furthermore, BOLD responses were detected in the IC when a pair of UHF pure tones was presented simultaneously (45 & 55kHz, 55 & 65kHz, 45 & 65kHz, 45 & 75kHz). For all four pairs, a cluster of voxels in the ventromedial side always showed the strongest responses, displaying combination sensitivity. Meanwhile, voxels in the dorsolateral side that showed strongest secondary responses to each pair of UHF pure tones also showed the strongest responses to a pure tone at their difference frequency, suggesting that they are sensitive to cochlear distortion. These BOLD fMRI results indicated that combination sensitivity and cochlear distortion are employed by large but spatially distinctive neuron populations in the IC to represent UHFs. Our imaging findings provided insights for understanding sound feature encoding in the early stage of the auditory pathway.
Collapse
Affiliation(s)
- Patrick P Gao
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Jevin W Zhang
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Russell W Chan
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Alex T L Leong
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Ed X Wu
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; Department of Anatomy, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; Department of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
| |
Collapse
|
37
|
Abstract
It is well established that the cholesterol-transporter apolipoprotein ε (APOE) genotype is associated with the risk of developing neurodegenerative diseases. Recently, brain functional connectivity (FC) in apoE-ε4 carriers has been investigated by means of resting-state fMRI, showing a marked differentiation in several functional networks at different ages compared with carriers of other apoE isoforms. The causes of such hampered FC are not understood. We hypothesize that vascular function and synaptic repair processes, which are both impaired in carriers of ε4, are the major contributors to the loss of FC during aging. To test this hypothesis, we integrated several different MRI techniques with immunohistochemistry and investigated FC changes in relation with perfusion, diffusion, and synaptic density in apoE4 and apoE-knock-out (KO) mice at 12 (adult) and 18 months of age. Compared with wild-type mice, we detected FC deficits in both adult and old apoE4 and apoE-KO mice. In apoE4 mice, these changes occurred concomitant with increased mean diffusivity in the hippocampus, whereas perfusion deficits appear only later in life, together with reduced postsynaptic density levels. Instead, in apoE-KO mice FC deficits were mirrored by strongly reduced brain perfusion since adulthood. In conclusion, we provide new evidence for a relation between apoE and brain connectivity, possibly mediated by vascular risk factors and by the efficiency of APOE as synaptic modulator in the brain. Our results show that multimodal MR neuroimaging is an excellent tool to assess brain function and to investigate early neuropathology and aging effects in translational research.
Collapse
|
38
|
Pittau F, Mégevand P, Sheybani L, Abela E, Grouiller F, Spinelli L, Michel CM, Seeck M, Vulliemoz S. Mapping epileptic activity: sources or networks for the clinicians? Front Neurol 2014; 5:218. [PMID: 25414692 PMCID: PMC4220689 DOI: 10.3389/fneur.2014.00218] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 10/08/2014] [Indexed: 01/03/2023] Open
Abstract
Epileptic seizures of focal origin are classically considered to arise from a focal epileptogenic zone and then spread to other brain regions. This is a key concept for semiological electro-clinical correlations, localization of relevant structural lesions, and selection of patients for epilepsy surgery. Recent development in neuro-imaging and electro-physiology and combinations, thereof, have been validated as contributory tools for focus localization. In parallel, these techniques have revealed that widespread networks of brain regions, rather than a single epileptogenic region, are implicated in focal epileptic activity. Sophisticated multimodal imaging and analysis strategies of brain connectivity patterns have been developed to characterize the spatio-temporal relationships within these networks by combining the strength of both techniques to optimize spatial and temporal resolution with whole-brain coverage and directional connectivity. In this paper, we review the potential clinical contribution of these functional mapping techniques as well as invasive electrophysiology in human beings and animal models for characterizing network connectivity.
Collapse
Affiliation(s)
- Francesca Pittau
- EEG and Epilepsy Unit, Neurology Department, University Hospitals and Faculty of Medicine of Geneva , Geneva , Switzerland
| | - Pierre Mégevand
- Laboratory for Multimodal Human Brain Mapping, Hofstra North Shore LIJ School of Medicine , Manhasset, NY , USA
| | - Laurent Sheybani
- Functional Brain Mapping Laboratory, Department of Fundamental Neurosciences, University of Geneva , Geneva , Switzerland
| | - Eugenio Abela
- Support Center of Advanced Neuroimaging (SCAN), Institute for Diagnostic and Interventional Neuroradiology, University Hospital Inselspital , Bern , Switzerland
| | - Frédéric Grouiller
- Radiology Department, University Hospitals and Faculty of Medicine of Geneva , Geneva , Switzerland
| | - Laurent Spinelli
- EEG and Epilepsy Unit, Neurology Department, University Hospitals and Faculty of Medicine of Geneva , Geneva , Switzerland
| | - Christoph M Michel
- Functional Brain Mapping Laboratory, Department of Fundamental Neurosciences, University of Geneva , Geneva , Switzerland
| | - Margitta Seeck
- EEG and Epilepsy Unit, Neurology Department, University Hospitals and Faculty of Medicine of Geneva , Geneva , Switzerland
| | - Serge Vulliemoz
- EEG and Epilepsy Unit, Neurology Department, University Hospitals and Faculty of Medicine of Geneva , Geneva , Switzerland
| |
Collapse
|
39
|
Abstract
The brain is highly plastic after stroke or epilepsy; however, there is a paucity of brain plasticity investigation after traumatic brain injury (TBI). This mini review summarizes the most recent evidence of brain plasticity in human TBI patients from the perspective of advanced magnetic resonance imaging. Similar to other forms of acquired brain injury, TBI patients also demonstrated both structural reorganization as well as functional compensation by the recruitment of other brain regions. However, the large scale brain network alterations after TBI are still unknown, and the field is still short of proper means on how to guide the choice of TBI rehabilitation or treatment plan to promote brain plasticity. The authors also point out the new direction of brain plasticity investigation.
Collapse
Affiliation(s)
- Zhifeng Kou
- Department of Biomedical Engineering, Wayne State University, Detroit, MI, USA ; Department of Radiology, Wayne State University, Detroit, MI, USA
| | - Armin Iraji
- Department of Biomedical Engineering, Wayne State University, Detroit, MI, USA
| |
Collapse
|