Altered functional and anatomical connectivity in schizophrenia.
BACKGROUND
Schizophrenia is characterized by a lack of integration between thought, emotion, and behavior. A disruption in the connectivity between brain processes may underlie this schism. Functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) were used to evaluate functional and anatomical brain connectivity in schizophrenia.


METHODS
In all, 29 chronic schizophrenia patients (11 females, age: mean=41.3, SD=9.28) and 29 controls (11 females, age: mean=41.1, SD=10.6) were recruited. Schizophrenia patients were assessed for severity of negative and positive symptoms and general cognitive abilities of attention/concentration and memory. Participants underwent a resting-fMRI scan and a DTI scan. For fMRI data, a hybrid independent components analysis was used to extract the group default mode network (DMN) and accompanying time-courses. Voxel-wise whole-brain multiple regressions with corresponding DMN time-courses was conducted for each subject. A t-test was conducted on resulting DMN correlation maps to look between-group differences. For DTI data, voxel-wise statistical analysis of the fractional anisotropy data was carried out to look for between-group differences. Voxel-wise correlations were conducted to investigate the relationship between brain connectivity and behavioral measures.


RESULTS
Results revealed altered functional and anatomical connectivity in medial frontal and anterior cingulate gyri of schizophrenia patients. In addition, frontal connectivity in schizophrenia patients was positively associated with symptoms as well as with general cognitive ability measures.


CONCLUSIONS
The present study shows convergent fMRI and DTI findings that are consistent with the disconnection hypothesis in schizophrenia, particularly in medial frontal regions, while adding some insight of the relationship between brain disconnectivity and behavior.
Camchong
Jazmin
J
Department of Psychiatry, University of Minnesota, 717 Delaware Street SE, Suite 516, Minneapolis, MN 55414, USA. camch001@umn.edu
MacDonald
Angus W
AW
Bell
Christopher
C
Mueller
Bryon A
BA
Lim
Kelvin O
KO
D000328:Adult; D001921:Brain / Q000473:pathology* / Q000503:physiopathology*; D016022:Case-Control Studies; D003071:Cognition; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory; D008875:Middle Aged; D009434:Neural Pathways / Q000473:pathology* / Q000503:physiopathology*; D017397:Prefrontal Cortex / Q000473:pathology / Q000503:physiopathology; D012559:Schizophrenia / Q000473:pathology*; D012565:Schizophrenic Psychology