Smaller left Heschl's gyrus volume in patients with schizotypal personality disorder.
OBJECTIVE
Individuals with schizophrenia spectrum disorders evince similar genetic, neurotransmitter, neuropsychological, electrophysiological, and structural abnormalities. Magnetic resonance imaging (MRI) studies have shown smaller gray matter volume in patients with schizotypal personality disorder than in matched comparison subjects in the left superior temporal gyrus, an area important for language processing. In a further exploration, the authors studied two components of the superior temporal gyrus: Heschl's gyrus and the planum temporale.


METHODS
MRI scans were acquired from 21 male, neuroleptic-naive subjects recruited from the community who met DSM-IV criteria for schizotypal personality disorder and 22 male comparison subjects similar in age. Eighteen of the 21 subjects with schizotypal personality disorder had additional comorbid, nonpsychotic diagnoses. The superior temporal gyrus was manually delineated on coronal images with subsequent identification of Heschl's gyrus and the planum temporale. Exploratory correlations between region of interest volumes and neuropsychological measures were also performed.


RESULTS
Left Heschl's gyrus gray matter volume was 21% smaller in the schizotypal personality disorder subjects than in the comparison subjects, a difference that was not associated with the presence of comorbid axis I disorders. There were no between-group volume differences in right Heschl's gyrus or in the right or left planum temporale. Exploratory analyses also showed a correlation between poor logical memory and smaller left Heschl's gyrus volume.


CONCLUSIONS
Smaller left Heschl's gyrus gray matter volume in subjects with schizotypal personality disorder may help to explain the previously reported abnormality in the left superior temporal gyrus and may be a vulnerability marker for schizophrenia spectrum disorders.
Harvard Medical School, Clinical Neuroscience Division, Department of Psychiatry, VA Boston HealthCare System, Brockton, MA 02401, USA.
Chandlee C
CC
Dickey
Robert W
RW
McCarley
Martina M
MM
Voglmaier
Melissa
M
Frumin
Margaret A
MA
Niznikiewicz
Yoshio
Y
Hirayasu
Stephanie
S
Fraone
Larry J
LJ
Seidman
Martha E
ME
Shenton
D000328:Adult; D001303:Auditory Cortex / Q000033:anatomy & histology* / Q000503:physiopathology; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D007360:Intelligence; D008279:Magnetic Resonance Imaging / Q000706:statistics & numerical data; D008297:Male; D009483:Neuropsychological Tests; D012569:Schizotypal Personality Disorder / Q000175:diagnosis* / Q000503:physiopathology; D012720:Severity of Illness Index; D012959:Socioeconomic Factors; D013702:Temporal Lobe / Q000033:anatomy & histology* / Q000503:physiopathology; D014706:Verbal Learning