Ventral striatum gray matter density reduction in patients with schizophrenia and psychotic emotional dysregulation.
BACKGROUND
Substantial heterogeneity remains across studies investigating changes in gray matter in schizophrenia. Differences in methodology, heterogeneous symptom patterns and symptom trajectories may contribute to inconsistent findings. To address this problem, we recently proposed to group patients by symptom dimensions, which map on the language, the limbic and the motor systems. The aim of the present study was to investigate whether patients with prevalent symptoms of emotional dysregulation would show structural neuronal abnormalities in the limbic system.


METHODS
43 right-handed medicated patients with schizophrenia were assessed with the Bern Psychopathology Scale (BPS). The patients and a control group of 34 healthy individuals underwent structural imaging at a 3T MRI scanner. Whole brain voxel-based morphometry (VBM) was compared between patient subgroups with different severity of emotional dysregulation. Group comparisons (comparison between patients with severe emotional dysregulation, patients with mild emotional dysregulation, patients with no emotional dysregulation and healthy controls) were performed using a one way ANOVA and ANCOVA respectively.


RESULTS
Patients with severe emotional dysregulation had significantly decreased gray matter density in a large cluster including the right ventral striatum and the head of the caudate compared to patients without emotional dysregulation. Comparing patients with severe emotional dysregulation and healthy controls, several clusters of significant decreased GM density were detected in patients, including the right ventral striatum, head of the caudate, left hippocampus, bilateral thalamus, dorsolateral prefrontal and orbitofrontal cortex. The significant effect in the ventral striatum was lost when patients with and without emotional dysregulation were pooled and compared with controls.


CONCLUSIONS
Decreased gray matter density in a large cluster including the right ventral striatum was associated with severe symptoms of emotional dysregulation in patients with schizophrenia. The ventral striatum is an important part of the limbic system, and was indicated to be involved in the generation of incentive salience and psychotic symptoms. Only patients with severe emotional dysregulation had decreased gray matter in several brain structures associated with emotion and reward processing compared to healthy controls. The results support the hypothesis that grouping patients according to specific clinical symptoms matched to the limbic system allows identifying patient subgroups with structural abnormalities in the limbic network.
University Hospital of Psychiatry, Bern, Switzerland.
Katharina
K
Stegmayer
University Hospital of Psychiatry, Bern, Switzerland.
Helge
H
Horn
University Hospital of Psychiatry, Bern, Switzerland.
Andrea
A
Federspiel
University Hospital of Psychiatry, Bern, Switzerland.
Nadja
N
Razavi
University Hospital of Psychiatry, Bern, Switzerland.
Tobias
T
Bracht
University Hospital of Psychiatry, Bern, Switzerland.
Karin
K
Laimböck
University Hospital of Psychiatry, Bern, Switzerland.
Werner
W
Strik
University Hospital of Psychiatry, Bern, Switzerland.
Thomas
T
Dierks
Support Center of Advanced Neuroimaging (SCAN), University Institute of Diagnostic and Interventional Neuroradiology, Inselspital, Bern, Switzerland.
Roland
R
Wiest
University Hospital of Psychiatry, Bern, Switzerland.
Thomas J
TJ
Müller
University Hospital of Psychiatry, Bern, Switzerland.
Sebastian
S
Walther
D000328:Adult; D000704:Analysis of Variance; D016009:Chi-Square Distribution; D005260:Female; D066128:Gray Matter / Q000473:pathology*; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000473:pathology*; D012559:Schizophrenia / Q000473:pathology*; D013223:Statistics as Topic; D066328:Ventral Striatum / Q000473:pathology*
Brain circuits; Dimensions; Emotional dysregulation; Limbic system; Psychopathology