Atypical hemispheric specialization for language in right-handed schizophrenia patients.
BACKGROUND
The literature suggests that schizophrenia could be related to a failure in the setting up of left hemisphere dominance for language. We sought to determine hemispheric specialization for language in schizophrenic patients, using functional magnetic resonance imaging.


METHODS
Twenty-one right-handed patients with DSM-IV schizophrenia and 21 right-handed control subjects matched by age, gender, and level of education were recruited. Fractional blood oxygen level dependent (BOLD) signal variations in anatomic regions of interest were compared between groups. Functional asymmetry indices (FAIs) were calculated in a region (LANG) resulting from the merging of activated regions showing a Group x Hemisphere interaction. The FAI difference between each patient and their matched control subject was computed.


RESULTS
We found lower BOLD signal changes in patients as compared with their control subjects in a network comprising areas of the left middle temporal gyrus, the left angular gyrus, and the pars triangularis of the left inferior frontal gyrus, merged to constitute LANG. The intra-pair differences of FAIs in this area showed that 76% of the patients exhibited less leftward functional asymmetry than their matched control subjects, including six patients with a rightward asymmetry.


CONCLUSIONS
These results demonstrated the existence of an anomaly in left hemisphere specialization for language in schizophrenic subjects.
Dollfus
Sonia
S
Groupe d'Imagerie Neurofonctionnelle, Unité Mixte de Recherche 6194 Centre National de la Recherche Scientifique/Commissariat à l'Engergie Atomique/Universités de Caen and Paris 5, Centre Cyceron, Caen Cedex, France. dollfus-s@chu-caen.fr
Razafimandimby
Annick
A
Delamillieure
Pascal
P
Brazo
Perrine
P
Joliot
Marc
M
Mazoyer
Bernard
B
Tzourio-Mazoyer
Nathalie
N
D000328:Adult; D000704:Analysis of Variance; D001931:Brain Mapping; D016022:Case-Control Studies; D032882:Comprehension / Q000502:physiology; D004292:Dominance, Cerebral; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D007802:Language; D007807:Language Tests / Q000706:statistics & numerical data; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D010100:Oxygen / Q000097:blood; D012559:Schizophrenia / Q000503:physiopathology*
D010100:Oxygen