Association between smaller left posterior superior temporal gyrus volume on magnetic resonance imaging and smaller left temporal P300 amplitude in first-episode schizophrenia.
BACKGROUND
In chronic schizophrenia, the P300 is broadly reduced and shows a localized left temporal deficit specifically associated with reduced gray matter volume of the left posterior superior temporal gyrus (STG). In first-episode patients, a similar left temporal P300 deficit is present in schizophrenia, but not in affective psychosis. The present study investigated whether the left temporal P300-left posterior STG volume association is selectively present in first-episode schizophrenia.


METHODS
P300 was recorded as first-episode subjects with schizophrenia (n = 15) or affective psychosis (n = 18) or control subjects (n = 18) silently counted infrequent target tones amid standard tones. High-resolution spoiled gradient-recalled acquisition magnetic resonance images provided quantitative measures of temporal lobe gray matter regions of interest.


RESULTS
Patients with first-episode schizophrenia displayed a reversed P300 temporal area asymmetry (smaller on the left), while magnetic resonance imaging showed smaller gray matter volumes of left posterior STG relative to control subjects and patients with affective psychosis (15.4% and 11.0%, respectively), smaller gray matter volumes of left planum temporale (21.0% relative to both), and a smaller total Heschl's gyrus volume (14.6% and 21.1%, respectively). Left posterior STG and the left planum temporale, but not other regions of interest, were specifically and positively correlated (r>0.5) with left temporal P300 voltage in patients with schizophrenia but not in patients with affective psychosis or in control subjects.


CONCLUSIONS
These results suggest that the left temporal P300 abnormality specifically associated with left posterior STG gray matter volume reduction is present at the first hospitalization for schizophrenia but is not present at the first hospitalization for affective psychosis.
McCarley
Robert W
RW
Deprtment of Psychiatry, Harvard medical School, Veterans Affairs Boston Healthcare System, 940 Belmont St, Brockton, MA 02301, USA. robert_mccarley@hms.harvard.edu
Salisbury
Dean F
DF
Hirayasu
Yoshio
Y
Yurgelun-Todd
Deborah A
DA
Tohen
Mauricio
M
Zarate
Carlos
C
Kikinis
Ron
R
Jolesz
Ferenc A
FA
Shenton
Martha E
ME
D000293:Adolescent; D000328:Adult; D002908:Chronic Disease; D003072:Cognition Disorders / Q000175:diagnosis / Q000209:etiology; D004569:Electroencephalography; D018913:Event-Related Potentials, P300 / Q000502:physiology*; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology*; D013702:Temporal Lobe / Q000002:abnormalities*