Functional lateralization of the sensorimotor cortex in patients with schizophrenia: effects of treatment with olanzapine.
BACKGROUND
Earlier cross-sectional studies with functional magnetic resonance imaging (fMRI) in treated patients with schizophrenia have reported abnormalities of cortical motor processing, including reduced lateralization of primary sensory motor cortex. The objective of the present longitudinal study was to evaluate whether such cortical abnormalities represent state or trait phenomena of the disorder.


METHODS
Seventeen acutely ill, previously untreated patients were studied after 4 weeks and after 8 weeks of olanzapine therapy. Seventeen matched healthy subjects served as control subjects. All subjects underwent two fMRI scans 4 weeks apart during a visually paced motor task using a simple periodic block design. Functional magnetic resonance imaging data were analyzed in Statistical Parametric Mapping (SPM99). Region of interest analyses were used to determine a laterality quotient (an index of lateralization) of motor cortical regions.


RESULTS
The fMRI data indicated that patients had reduced activation of the primary sensory motor cortex at 4 weeks but not at 8 weeks; however, the laterality quotient in the primary sensory motor cortex was reduced in patients at both time points.


CONCLUSIONS
These results suggest that some cortical abnormalities during motor processing represent state phenomena, whereas reduced functional lateralization of the primary sensory motor cortex represents an enduring trait of schizophrenia.
Psychiatric Neuroscience Group, Section on Mental Disorders, Department of Psychiatric and Neurological Sciences, University of Bari, Bari, Italy.
Alessandro
A
Bertolino
Giuseppe
G
Blasi
Grazia
G
Caforio
Valeria
V
Latorre
Mariapia
M
De Candia
Valeria
V
Rubino
Joseph H
JH
Callicott
Venkata S
VS
Mattay
Antonello
A
Bellomo
Tommaso
T
Scarabino
Daniel R
DR
Weinberger
Marcello
M
Nardini
D000293:Adolescent; D000328:Adult; D014150:Antipsychotic Agents / Q000494:pharmacology* / Q000627:therapeutic use; D001569:Benzodiazepines / Q000494:pharmacology* / Q000627:therapeutic use; D001931:Brain Mapping; D005260:Female; D007839:Functional Laterality / Q000187:drug effects*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009044:Motor Cortex / Q000098:blood supply / Q000187:drug effects* / Q000473:pathology; D000077152:Olanzapine; D012559:Schizophrenia / Q000188:drug therapy / Q000503:physiopathology*; D013003:Somatosensory Cortex / Q000098:blood supply / Q000187:drug effects* / Q000473:pathology; D013997:Time Factors
D014150:Antipsychotic Agents; D001569:Benzodiazepines; D000077152:Olanzapine