scholarly journals White matter variability, cognition, and disorders: a systematic review.

2021 ◽  
Author(s):  
Stephanie J. Forkel ◽  
Patrick Friedrich ◽  
Michel Thiebaut de Schotten ◽  
Henrietta Howells
Keyword(s):  
Systematic Review ◽  
White Matter ◽  
Clinical Symptoms ◽  
Individual Variability ◽  
Cerebral White Matter ◽  
Brain Anatomy ◽  
Loss Of Function ◽  
Cross Sectional ◽  
Functional Laterality ◽  
Functional Organisation

Abstract Inter-individual differences can inform treatment procedures and - if accounted for - have the potential to significantly improve patient outcomes. However, when studying brain anatomy, these inter-individual variations are commonly unaccounted for, despite reports of differences in gross anatomical features, cross-sectional and connectional anatomy. Brain connections are essential to facilitate functional organisation and, when severed, cause impairments or complete loss of function. Hence the study of cerebral white matter may be an ideal compromise to capture inter-individual variability in structure and function. We reviewed the wealth of studies that associate functions and clinical symptoms with individual tracts using diffusion tractography. Our systematic review indicates that tractography has proven to be a sensitive method in neurology, psychiatry and healthy populations to identify variability and its functional correlates. However, the literature may be biased, as we determined that the most commonly studied tracts are not necessarily those with the highest sensitivity to cognitive functions and pathologies. Additionally, the side of the studied tract is often unreported, thus neglecting functional laterality and hemispheric asymmetries. Finally, we demonstrate that tracts, as we define them, are not usually correlated with only one, but rather multiple cognitive domains or pathologies. While our systematic review identified some methodological caveats, it also suggests that tract-function correlations might be a promising biomarker for precision medicine. It characterises variations in brain anatomy, differences in functional organisation, and predicting resilience or recovery in patients.

scholarly journals White matter variability, cognition, and disorders: a systematic review

2020 ◽  
Author(s):  
Stephanie J. Forkel ◽  
Patrick Friedrich ◽  
Michel Thiebaut de Schotten ◽  
Henrietta Howells
Keyword(s):  
Systematic Review ◽  
White Matter ◽  
Clinical Symptoms ◽  
Individual Variability ◽  
Cerebral White Matter ◽  
Brain Anatomy ◽  
Loss Of Function ◽  
Functional Impairments ◽  
Cross Sectional ◽  
Functional Organisation

AbstractInter-individual differences can inform treatment procedures and - if accounted for - can significantly improve patient outcomes. However, when studying brain anatomy, these inter- individual variations are largely unaccounted for, despite reports of differences in gross anatomical features, cross-sectional and connectional anatomy. Brain connections are essential to mediate brain functional organisation and, when severed, cause functional impairments or complete loss of function. Hence the study of cerebral white matter may be an ideal compromise to capture inter-individual variability in structure and function. Here we reviewed the wealth of studies that associate functions and clinical symptoms with individual tracts using diffusion tractography. Our systematic review indicates that tractography has proven to be a sensitive method in neurology, psychiatry and healthy populations to identify variability and its functional correlates. However, the literature may be biased, as we identified that the most commonly reported tracts are not necessarily those with the highest sensitivity to cognitive functions and pathologies. Finally, we demonstrate that tracts, as we define them, are not usually correlated with only one, but rather multiple cognitive domains or pathologies. While our systematic review identified some methodological caveats, it also suggests that tract-function correlations might be a promising biomarker for precision medicine as it characterises variations in brain anatomy, differences in functional organisation and predict resilience or recovery in patients.

scholarly journals White matter variability, cognition, and disorders: a systematic review

2021 ◽  
Author(s):  
Stephanie J. Forkel ◽  
Patrick Friedrich ◽  
Michel Thiebaut de Schotten ◽  
Henrietta Howells
Keyword(s):  
Systematic Review ◽  
White Matter ◽  
Cognitive Functions ◽  
Functional Organization ◽  
Clinical Symptoms ◽  
Cerebral White Matter ◽  
Brain Anatomy ◽  
Loss Of Function ◽  
Cross Sectional ◽  
Functional Laterality

AbstractInter-individual differences can inform treatment procedures and—if accounted for—have the potential to significantly improve patient outcomes. However, when studying brain anatomy, these inter-individual variations are commonly unaccounted for, despite reports of differences in gross anatomical features, cross-sectional, and connectional anatomy. Brain connections are essential to facilitate functional organization and, when severed, cause impairments or complete loss of function. Hence, the study of cerebral white matter may be an ideal compromise to capture inter-individual variability in structure and function. We reviewed the wealth of studies that associate cognitive functions and clinical symptoms with individual tracts using diffusion tractography. Our systematic review indicates that tractography has proven to be a sensitive method in neurology, psychiatry, and healthy populations to identify variability and its functional correlates. However, the literature may be biased, as the most commonly studied tracts are not necessarily those with the highest sensitivity to cognitive functions and pathologies. Additionally, the hemisphere of the studied tract is often unreported, thus neglecting functional laterality and asymmetries. Finally, we demonstrate that tracts, as we define them, are not correlated with one, but multiple cognitive domains or pathologies. While our systematic review identified some methodological caveats, it also suggests that tract–function correlations might still be a promising tool in identifying biomarkers for precision medicine. They can characterize variations in brain anatomy, differences in functional organization, and predicts resilience and recovery in patients.

scholarly journals Characteristics of the corpus callosum in chronic schizophrenia treated with clozapine or risperidone and those never-treated

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Bo Tao ◽  
Yuan Xiao ◽  
Hengyi Cao ◽  
Wenjing Zhang ◽  
Chengmin Yang ◽  
...  
Keyword(s):  
White Matter ◽  
Corpus Callosum ◽  
Clinical Symptoms ◽  
Diffusion Tensor ◽  
Structural Characteristics ◽  
Chronic Schizophrenia ◽  
Cross Sectional Study ◽  
Antipsychotic Treatment ◽  
Cross Sectional

Abstract Background The corpus callosum (CC) deficits have been well documented in chronic schizophrenia. However, the long-term impacts of antipsychotic monotherapies on callosal anatomy remain unclear. This cross-sectional study sought to explore micro- and macro-structural characteristics of the CC in never-treated patients and those with long-term mono-antipsychotic treatment. Methods The study included 23 clozapine-treated schizophrenia patients (CT-SCZ), 19 risperidone-treated schizophrenia patients (RT-SCZ), 23 never-treated schizophrenia patients (NT-SCZ), and 35 healthy controls (HCs). High resolution structural images and diffusion tensor imaging (DTI) data for each participant were obtained via a 3.0 T MR scanner. FreeSurfer was used to examine the volumes and fractional anisotropy (FA) values of the CC for each participant. Results There were significant deficits in the total and sub-regional CC volume and white matter integrity in NT-SCZ in comparison with healthy subjects. Compared with NT-SCZ, both CT-SCZ and RT-SCZ showed significantly increased FA values in the anterior CC region, while only RT-SCZ showed significantly increased volume in the mid-anterior CC region. Moreover, the volume of the mid-anterior CC region was significantly smaller in CT-SCZ compared to HCs. No correlations of clinical symptoms with callosal metrics were observed in schizophrenia patients. Conclusions Our findings provide insight into micro- and macro-structural characteristics of the CC in chronic schizophrenia patients with or without antipsychotics. These results suggest that the pathology itself is responsible for cerebral abnormalities in schizophrenia and that chronic exposure to antipsychotics may have an impact on white matter structure of schizophrenia patients, especially in those with risperidone treatment.

scholarly journals Cerebral white matter free water

Neurology ◽  
2019 ◽  
Vol 92 (19) ◽  
pp. e2221-e2231 ◽  
Author(s):  
Pauline Maillard ◽  
Evan Fletcher ◽  
Baljeet Singh ◽  
Oliver Martinez ◽  
David K. Johnson ◽  
...  
Keyword(s):  
White Matter ◽  
Proportional Hazards ◽  
Functional Performance ◽  
Diffusion Tensor ◽  
Mean Diffusivity ◽  
Free Water ◽  
Cox Proportional Hazards ◽  
Cerebral White Matter ◽  
Clinical Dementia Rating ◽  
Cross Sectional

ObjectiveTo determine whether free water (FW) content, initially developed to correct metrics derived from diffusion tensor imaging and recently found to be strongly associated with vascular risk factors, may constitute a sensitive biomarker of white matter (WM) microstructural differences associated with cognitive performance but remains unknown.MethodsFive hundred thirty-six cognitively diverse individuals, aged 77 ± 8 years, received yearly comprehensive clinical evaluations and a baseline MRI examination of whom 224 underwent follow-up MRI. WM microstructural measures, including FW, fractional anisotropy, and mean diffusivity corrected for FW and WM hyperintensity burden were computed within WM voxels of each individual. Baseline and change in MRI metrics were then used as independent variables to explain baseline and change in episodic memory (EM), executive function (EF), and Clinical Dementia Rating (CDR) scores using linear, logistic, and Cox proportional-hazards regressions.ResultsHigher baseline FW and WM hyperintensity were associated with lower baseline EM and EF, higher baseline CDR, accelerated EF and EM decline, and higher probability to transition to a more severe CDR stage (p values <0.01). Annual change in FW was also found to be associated with concomitant change in cognitive and functional performance (p values <0.01).ConclusionsThis study finds cross-sectional and longitudinal associations between FW content and trajectory of cognitive and functional performance in a large sample of cognitively diverse individuals. It supports the need to investigate the pathophysiologic process that manifests increased FW, potentially leading to more severe WM territory injury and promoting cognitive and functional decline.

Implications of data-driven analyses for personalized therapy in psychosis: a systematic review of cluster- and trajectory-based modelling studies

2019 ◽  
Author(s):  
Tesfa Dejenie Habtewold ◽  
Lyan H. Rodijk ◽  
Edith J. Liemburg ◽  
Grigory Sidorenkov ◽  
H. Marike Boezen ◽  
...  
Keyword(s):  
Systematic Review ◽  
Longitudinal Studies ◽  
Cognitive Deficits ◽  
Negative Symptoms ◽  
Clinical Symptoms ◽  
Data Driven ◽  
Schizophrenia Spectrum Disorders ◽  
Cross Sectional ◽  
Modelling Studies ◽  
Positive And Negative Symptoms

AbstractIntroductionTo tackle the phenotypic heterogeneity of schizophrenia, data-driven methods are often applied to identify subtypes of its (sub)clinical symptoms though there is no systematic review.AimsTo summarize the evidence from cluster- and trajectory-based studies of positive, negative and cognitive symptoms in patients with schizophrenia spectrum disorders, their siblings and healthy people. Additionally, we aimed to highlight knowledge gaps and point out future directions to optimize the translatability of cluster- and trajectory-based studies.MethodsA systematic review was performed through searching PsycINFO, PubMed, PsycTESTS, PsycARTICLES, SCOPUS, EMBASE, and Web of Science electronic databases. Both cross-sectional and longitudinal studies published from 2008 to 2019, which reported at least two statistically derived clusters or trajectories were included. Two reviewers independently screened and extracted the data.ResultsOf 2,285 studies retrieved, 50 studies (17 longitudinal and 33 cross-sectional) conducted in 30 countries were selected for review. Longitudinal studies discovered two to five trajectories of positive and negative symptoms in patient, and four to five trajectories of cognitive deficits in patient and sibling. In cross-sectional studies, three clusters of positive and negative symptoms in patient, four clusters of positive and negative schizotypy in sibling, and three to five clusters of cognitive deficits in patient and sibling were identified. These studies also reported multidimensional predictors of clusters and trajectories.ConclusionsOur findings indicate that (sub)clinical symptoms of schizophrenia are more heterogeneous than currently recognized. Identified clusters and trajectories can be used as a basis for personalized psychiatry.

Gerstmann Meets Geschwind

2011 ◽  
Vol 17 (6) ◽  
pp. 633-644 ◽  
Author(s):  
Andreas Kleinschmidt ◽  
Elena Rusconi
Keyword(s):  
White Matter ◽  
Clinical Symptoms ◽  
Cerebral White Matter ◽  
Focal Lesion ◽  
Cortical Lesions ◽  
White Matter Damage ◽  
Fiber Tract ◽  
Fiber Tracts ◽  
Behavioral Neurology ◽  
Clinical Phenomenology

That disconnection causes clinical symptoms is a very influential concept in behavioral neurology. Criteria for subcortical disconnection usually are symptoms that are distinct from those following cortical lesions and damage to a single, long-range fiber tract. Yet, a recent study combining functional magnetic resonance imaging and fiber tracking concluded that a focal lesion in left parietal white matter provides the only tenable explanation for pure Gerstmann’s syndrome, an enigmatic tetrad of acalculia, agraphia, finger agnosia, and left-right disorientation. Such a lesion would affect not only a single fiber tract but crossing or “kissing” of different fiber tracts and hence disconnect separate cortical networks. As fiber crossing is prominent in the cerebral white matter, the authors propose an extension to the subcortical disconnection framework that opens the door to ascribing a more diversified clinical phenomenology to white matter damage and ensuing disconnection than has been the case so far.

scholarly journals White matter correlates of hemi-face dominance in happy and sad expression

2017 ◽  
Author(s):  
Stefano Ioannucci ◽  
Nathalie George ◽  
Patrick Friedrich ◽  
Leonardo Cerliani ◽  
Michel Thiebaut de Schotten
Keyword(s):  
White Matter ◽  
Emotional Expression ◽  
Individual Variability ◽  
Cerebral White Matter ◽  
List Type ◽  
Brain Hemispheres ◽  
Neural Underpinnings ◽  
Human Participants ◽  
Relationship Of ◽  
The Relationship

AbstractThe neural underpinnings of human emotional expression are thought to be unevenly distributed among the two brain hemispheres. However, little is known on the anatomy supporting this claim, particularly in the cerebral white matter. Here, we explored the relationship between hemi-face dominance in emotional expression and cerebral white matter asymmetries in 33 healthy participants. Measures of emotional expression were derived from pictures of the participant’s faces in a ‘happy smiling’ and a ‘sad frowning’ conditions. Chimeric faces were constructed by mirroring right and left hemi-faces, as done in previous studies, resulting in a left mirrored and right mirrored chimeric face per picture. To gain measures of hemi-face dominance per participant, a jury of 20 additional participants rated which chimeric face shows higher intensity of emotional expressivity, by marking a 155mm line between the two versions. Measures of the asymmetry of the uncinate, the cingulum and the three branches of superior longitudinal fasciculi were derived from diffusion weighted imaging tractography dissections. Group effect analyses indicated that the degree of asymmetry in emotional expression was not as prominent as reported in the literature and showed a large inter-individual variability. The degree of asymmetry in emotional expression was, however, significantly associated with the asymmetries in connective properties of the fronto-temporal and fronto-parietal tracts, specifically the uncinate fasciculus and the first branch of the superior longitudinal fasciculus. Therefore, this result raises novel hypotheses on the relationship of specific white matter tracts and emotional expression, especially their role in mood disorders.Ethical statementNone of the authors have a conflict of interestData collection from human participants was approved by the Comité de Protection des Personnes “CPP Ile de France V”All participants provided written informed consentFunding from ERC (grant agreement No. 818521) and “Agence Nationale de la Recherche” [grants numbers ANR-13-JSV4-0001-01 an ANR-10-IAIHU-06]

scholarly journals White Matter Abnormalities in Patients With Typhoon-Related Posttraumatic Stress Disorder

2021 ◽  
Vol 15 ◽  
Author(s):  
Hui Juan Chen ◽  
Rongfeng Qi ◽  
Jun Ke ◽  
Jie Qiu ◽  
Qiang Xu ◽  
...  
Keyword(s):  
Posttraumatic Stress Disorder ◽  
White Matter ◽  
Posttraumatic Stress ◽  
Stress Disorder ◽  
Clinical Symptoms ◽  
Diffusion Tensor ◽  
Traumatic Event ◽  
Mean Diffusivity ◽  
Cerebral White Matter ◽  
White Matter Abnormalities

Patients with posttraumatic stress disorder (PTSD) might have white matter abnormalities. However, less is known about white matter changes after exposing a specific traumatic event. The purpose of this study was to explore the abnormalities of diffusion in cerebral white matter and its relationship with the clinical symptoms in patients with PTSD by using diffusion tensor imaging (DTI). Diffusion-weighted imaging of the cerebrum was performed in typhoon survivors with (n = 27) and without PTSD (n = 33) and healthy controls (HCs) (n = 30). Differences in fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were calculated among groups using voxel-based analysis of the DTI data. Correlations between diffusion indices and clinical symptoms in patients with PTSD were also assessed. Both patients with PTSD and trauma-exposed control (TEC) group showed increased FA in the anterior limb of the internal capsule, forceps of the corpus callosum, and corona radiata relative to the HC group. Additionally, there was a negative correlation between FA values in the white matter and the clinical symptoms. Trauma exposure may result in disruption of cerebral white matter in individuals with or without PTSD, particularly in the frontal fibers. Aberrant white matter alterations may be associated with the severity of PTSD symptoms.

scholarly journals Relationship between carotid arterial properties and cerebral white matter hyperintensities

Neurology ◽  
2017 ◽  
Vol 88 (21) ◽  
pp. 2036-2042 ◽  
Author(s):  
Tatjana Rundek ◽  
David Della-Morte ◽  
Hannah Gardener ◽  
Chuanhui Dong ◽  
Matthew S. Markert ◽  
...  
Keyword(s):  
White Matter ◽  
Carotid Artery ◽  
Arterial Compliance ◽  
Cross Sectional Study ◽  
Stiffness Index ◽  
White Matter Hyperintensity ◽  
Cerebral White Matter ◽  
Large Artery ◽  
Cross Sectional ◽  
The Difference

Objective:Since arterial stiffness is a functional measure of arterial compliance and may be an important marker of cerebrovascular disease, we examined the association of carotid artery stiffness with white matter hyperintensity volume (WMHV) in a cross-sectional study of 1,166 stroke-free participants.Methods:Carotid beta stiffness index (STIFF) was assessed by M-mode ultrasound of the common carotid artery and calculated as the ratio of natural log of the difference between systolic and diastolic blood pressure over STRAIN, a ratio of the difference between carotid systolic and diastolic diameter (DD) divided by DD. WMHV was measured by fluid-attenuated inversion recovery MRI. The associations of STIFF, DD, and STRAIN with WMHV were examined using linear regression after adjusting for sociodemographic, lifestyle, and vascular risk factors.Results:In a fully adjusted model, larger carotid DD was significantly associated with greater log-WMHV (β = 0.09, p = 0.001). STIFF and STRAIN were not significantly associated with WMHV. In adjusted analyses stratified by race–ethnicity, STRAIN (β = −1.78, p = 0.002) and DD (β = 0.11, p = 0.001) were both associated with greater log-WMHV among Hispanic participants, but not among black or white participants.Conclusions:Large carotid artery diameters are associated with greater burden of white matter hyperintensity (WMH) in this multiethnic population. The association between increased diameters, decreased STRAIN, and greater WMH burden is more pronounced among Hispanics. These associations suggest a potential important pathophysiologic role of extracranial large artery remodeling in the burden of WMH.

scholarly journals White-matter lesions drive deep gray-matter atrophy in early multiple sclerosis: support from structural MRI

2013 ◽  
Vol 19 (11) ◽  
pp. 1485-1492 ◽  
Author(s):  
Mark Mühlau ◽  
Dorothea Buck ◽  
Annette Förschler ◽  
Christine C Boucard ◽  
Milan Arsic ◽  
...  
Keyword(s):  
White Matter ◽  
Gray Matter ◽  
Spatial Relationship ◽  
White Matter Lesions ◽  
Structural Mri ◽  
Cerebral White Matter ◽  
Cross Sectional ◽  
Axonal Pathology ◽  
Probability Maps ◽  
Deep Gray Matter

Background: In MS, the relationship between lesions within cerebral white matter (WM) and atrophy within deep gray matter (GM) is unclear. Objective: To investigate the spatial relationship between WM lesions and deep GM atrophy. Methods: We performed a cross-sectional structural magnetic resonance imaging (MRI) study (3 Tesla) in 249 patients with clinically-isolated syndrome or relapsing–remitting MS (Expanded Disability Status Scale score: median, 1.0; range, 0–4) and in 49 healthy controls. Preprocessing of T1-weighted and fluid-attenuated T2-weighted images resulted in normalized GM images and WM lesion probability maps. We performed two voxel-wise analyses: 1. We localized GM atrophy and confirmed that it is most pronounced within deep GM; 2. We searched for a spatial relationship between WM lesions and deep GM atrophy; to this end we analyzed WM lesion probability maps by voxel-wise multiple regression, including four variables derived from maxima of regional deep GM atrophy (caudate and pulvinar, each left and right). Results: Atrophy of each deep GM region was explained by ipsilateral WM lesion probability, in the area most densely connected to the respective deep GM region. Conclusion: We demonstrated that WM lesions and deep GM atrophy are spatially related. Our results are best compatible with the hypothesis that WM lesions contribute to deep GM atrophy through axonal pathology.

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