Expanding the response space in chronic schizophrenia: the relevance of left prefrontal cortex.
OBJECTIVE
This study probed the ability of people with chronic schizophrenia to control their behavior in time by requiring them to deliberately vary responses within the temporal domain (i.e., to avoid regular inter-response intervals).


METHODS
Thirteen schizophrenia patients performed single finger movements (at moments of their own choosing) in an event-related functional magnetic resonance imaging paradigm. Their performance was computed using the coefficient of variation of inter-response interval duration.


RESULTS
Task performance was positively correlated with activation of left lateral prefrontal cortex. Post hoc analyses revealed an inverse correlation between activation in this region and severity of attentional impairment.


CONCLUSIONS
These findings implicate left lateral prefrontal cortex in the modulation of the temporal response space in schizophrenia and imply greater attentional (executive) impairment among those who fail to modulate their behavior in time.
Ganesan
Venkatasubramanian
V
Academic Clinical Psychiatry, Division of Genomic Medicine, University of Sheffield, Longley Centre, Norwood Grange Drive, Sheffield S5 7JT, UK. g.v.s.manian@shef.ac.uk
Green
Russell D
RD
Hunter
Mike D
MD
Wilkinson
Iain D
ID
Spence
Sean A
SA
D000328:Adult; D001288:Attention / Q000502:physiology; D001479:Basal Ganglia / Q000503:physiopathology; D001931:Brain Mapping; D002908:Chronic Disease; D004292:Dominance, Cerebral / Q000502:physiology*; D005385:Fingers / Q000294:innervation*; D006801:Humans; D007089:Image Enhancement; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D009044:Motor Cortex / Q000503:physiopathology; D009434:Neural Pathways / Q000503:physiopathology; D010100:Oxygen / Q000097:blood*; D017397:Prefrontal Cortex / Q000503:physiopathology*; D011569:Psychiatric Status Rating Scales; D011930:Reaction Time / Q000502:physiology*; D012559:Schizophrenia / Q000503:physiopathology* / Q000628:therapy; D012565:Schizophrenic Psychology; D013223:Statistics as Topic; D013239:Stereotyped Behavior / Q000502:physiology*
D010100:Oxygen