Do sex differences affect prefrontal cortex associated cognition in schizophrenia?
Cognitive deficits in schizophrenia, especially those related to prefrontal cortex (PFC) functions, influence functional outcome. There is evidence for sex differences in cognition in schizophrenia, but the results in the literature are still controversial.


OBJECTIVE
This study evaluated different modalities of working memory (WM) and executive control (EC), functions that are both associated with the PFC, between sexes in schizophrenic patients and controls.


METHODS
We used a battery of neuropsychological tests for assessing auditory, spatial, and visual-matching WM and used a dual task for assessing EC. The study included 50 inpatients (25 female) partially remitted and taking atypical neuroleptics, as well as 40 controls (20 female) matched for age and education.


RESULTS
Significant sex differences were found in the dual task; female patients detected fewer correct trials than male patients and controls did. Moreover, female patients performed significantly worse in the single visual subtest of the dual task. For the controls, no sex differences were found. Males showed higher positive symptoms than females, but no other differences in psychopathology, disease characteristics, or extrapyramidal symptoms were found between sexes.


CONCLUSIONS
The present study shows an absence of sex differences in WM in healthy subjects and in patients with schizophrenia. However, in the dual task and in the single visual subtest, female patients performed worse than males. This finding suggests that in contrast to males, nonacute female inpatients show an underlying attentional deficit that may contribute to impairment in higher-order functions such as EC.
Roesch-Ely
Daniela
D
Department of General Adult Psychiatry, University of Heidelberg, Heidelberg, Germany. daniela_roesch@med.uni-heidelberg.de
Hornberger
Eva
E
Weiland
Stephan
S
Hornstein
Christiane
C
Parzer
Peter
P
Thomas
Christine
C
Weisbrod
Matthias
M
D000328:Adult; D001288:Attention / Q000502:physiology; D003072:Cognition Disorders / Q000175:diagnosis / Q000503:physiopathology* / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term; D009146:Music; D009483:Neuropsychological Tests / Q000706:statistics & numerical data*; D009949:Orientation / Q000502:physiology; D010364:Pattern Recognition, Visual / Q000502:physiology; D010897:Pitch Discrimination / Q000502:physiology; D017397:Prefrontal Cortex / Q000503:physiopathology*; D011340:Problem Solving / Q000502:physiology; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data; D011594:Psychometrics; D011597:Psychomotor Performance / Q000502:physiology; D011618:Psychotic Disorders / Q000175:diagnosis / Q000503:physiopathology* / Q000523:psychology; D012559:Schizophrenia / Q000175:diagnosis / Q000503:physiopathology*; D012565:Schizophrenic Psychology; D012737:Sex Factors