Structural connectivity of the anterior cingulate in children with unilateral cerebral palsy due to white matter lesions

Abstract Schizophrenia (SZ) and bipolar disorder (BD) are often conceptualized as “disconnection syndromes,” with substantial evidence of abnormalities in deep white matter tracts, forming the substrates of long-range connectivity, seen in both disorders. However, the study of superficial white matter (SWM) U-shaped short-range tracts remained challenging until recently, although findings from postmortem studies suggest they are likely integral components of SZ and BD neuropathology. This diffusion weighted imaging (DWI) study aimed to investigate SWM microstructure in vivo in both SZ and BD for the first time. We performed whole brain tractography in 31 people with SZ, 32 people with BD and 54 controls using BrainVISA and Connectomist 2.0. Segmentation and labeling of SWM tracts were performed using a novel, comprehensive U-fiber atlas. Analysis of covariances yielded significant generalized fractional anisotropy (gFA) differences for 17 SWM bundles in frontal, parietal, and temporal cortices. Post hoc analyses showed gFA reductions in both patient groups as compared with controls in bundles connecting regions involved in language processing, mood regulation, working memory, and motor function (pars opercularis, insula, anterior cingulate, precentral gyrus). We also found increased gFA in SZ patients in areas overlapping the default mode network (inferior parietal, middle temporal, precuneus), supporting functional hyperconnectivity of this network evidenced in SZ. We thus illustrate that short U-fibers are vulnerable to the pathological processes in major psychiatric illnesses, encouraging improved understanding of their anatomy and function.

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Positive symptoms and white matter microstructure in never-medicated first episode schizophrenia

Psychological Medicine ◽

10.1017/s003329171000156x ◽

2010 ◽

Vol 41 (8) ◽

pp. 1709-1719 ◽

Cited By ~ 66

Author(s):

V. Cheung ◽

C. P. Y. Chiu ◽

C. W. Law ◽

C. Cheung ◽

C. L. M. Hui ◽

...

Keyword(s):

White Matter ◽

Negative Symptoms ◽

Diffusion Tensor ◽

Structural Connectivity ◽

Anterior Cingulate ◽

Middle Temporal Gyrus ◽

First Episode ◽

Positive Symptoms ◽

Cingulate Gyrus ◽

First Episode Schizophrenia

BackgroundWe investigated cerebral structural connectivity and its relationship to symptoms in never-medicated individuals with first-onset schizophrenia using diffusion tensor imaging (DTI).MethodWe recruited subjects with first episode DSM-IV schizophrenia who had never been exposed to antipsychotic medication (n=34) and age-matched healthy volunteers (n=32). All subjects received DTI and structural magnetic resonance imaging scans. Patients' symptoms were assessed on the Positive and Negative Syndrome Scale. Voxel-based analysis was performed to investigate brain regions where fractional anisotropy (FA) values significantly correlated with symptom scores.ResultsIn patients with first-episode schizophrenia, positive symptoms correlated positively with FA scores in white matter associated with the right frontal lobe, left anterior cingulate gyrus, left superior temporal gyrus, right middle temporal gyrus, right middle cingulate gyrus, and left cuneus. Importantly, FA in each of these regions was lower in patients than controls, but patients with more positive symptoms had FA values closer to controls. We found no significant correlations between FA and negative symptoms.ConclusionsThe newly-diagnosed, neuroleptic-naive patients had lower FA scores in the brain compared with controls. There was positive correlation between FA scores and positive symptoms scores in frontotemporal tracts, including left fronto-occipital fasciculus and left inferior longitudinal fasciculus. This implies that white matter dysintegrity is already present in the pre-treatment phase and that FA is likely to decrease after clinical treatment or symptom remission.

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Increased and decreased superficial white matter structural connectivity in schizophrenia and bipolar disorder

10.1101/473686 ◽

2018 ◽

Author(s):

Ellen Ji ◽

Pamela Guevara ◽

Miguel Guevara ◽

Antoine Grigis ◽

Nicole Labra ◽

...

Keyword(s):

Bipolar Disorder ◽

White Matter ◽

Language Processing ◽

Structural Connectivity ◽

Anterior Cingulate ◽

Precentral Gyrus ◽

Psychiatric Illnesses ◽

And Function ◽

Post Hoc

AbstractSchizophrenia (SZ) and bipolar disorder (BD) are often conceptualized as “disconnection syndromes”, with substantial evidence of abnormalities in deep white matter tracts, forming the substrates of long-range connectivity, seen in both disorders. However, the study of superficial white matter (SWM) U-shaped short-range tracts remained challenging until recently, although findings from post-mortem studies suggest they are likely integral components of SZ and BD neuropathology. This diffusion weighted imaging (DWI) study aimed to investigate SWM microstructure in vivo in both SZ and BD for the first time. We performed whole brain tractography in 31 people with SZ, 32 people with BD and 54 controls using BrainVISA and Connectomist 2.0. Segmentation and labelling of SWM tracts were performed using a novel, comprehensive U-fiber atlas. Analysis of covariances yielded significant generalized fractional anisotropy (gFA) differences for 17 SWM bundles in frontal, parietal and temporal cortices. Post hoc analyses showed gFA reductions in both patient groups as compared with controls in bundles connecting regions involved in language processing, mood regulation, working memory and motor function (pars opercularis, insula, anterior cingulate, precentral gyrus). We also found increased gFA in SZ patients in areas overlapping the default mode network (inferior parietal, middle temporal, precuneus), supporting functional hyperconnectivity of this network evidenced in SZ. We thus illustrate that short U-fibers are vulnerable to the pathological processes in major psychiatric illnesses, encouraging improved understanding of their anatomy and function.

Download Full-text