Schizoaffective disorder: evidence for reversed cerebral asymmetry.
BACKGROUND
Schizoaffective disorder is one of the most severe of the affective psychoses, but its pathophysiology is poorly understood. Because cerebral lateralization may be disturbed in psychotic disorders generally, studies examining cerebral asymmetry may improve understanding of the neurobiology specific to schizoaffective disorder. This study examines cerebral lateralization in this patient population using magnetic source localization.


METHODS
We studied 16 subjects with schizoaffective disorder and 16 controls. Magnetic source localization was used to identify the location of the 20 msec latency somatosensory evoked field component (M20).


RESULTS
In control subjects, the source location was further anterior in the right hemisphere. The subjects with schizoaffective disorder were reverse lateralized.


CONCLUSIONS
The findings of a reversed asymmetry of the M20 in patients with schizoaffective disorder suggest an anatomical shift in the placement of the post central gyrus in this disorder, compatible with a disorder of cerebral lateralization. Whether this finding converges or diverges with measurement of the M20 in other psychotic disorders will require further investigation.
Reite
M
M
Department of Psychiatry, University of Colorado Health Sciences Center, Denver 80262, USA.
Teale
P
P
Rojas
D C
DC
Sheeder
J
J
Arciniegas
D
D
D000328:Adult; D001921:Brain / Q000002:abnormalities*; D005073:Evoked Potentials, Somatosensory; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D015225:Magnetoencephalography / Q000379:methods; D008297:Male; D011618:Psychotic Disorders / Q000175:diagnosis / Q000209:etiology*; D012984:Software