Functional magnetic resonance imaging study of cognitive control in the healthy relatives of schizophrenia patients.
BACKGROUND
The predisposition, or diathesis, to schizophrenia is highly heritable. The manner in which this genetic diathesis is manifest in the central nervous system is largely unknown, although healthy relatives of schizophrenia patients show executive processing deficits associated with prefrontal cortical impairments.


METHODS
The current study evaluated brain activity in 21 healthy relatives of schizophrenia patients and 20 demographically similar control subjects during correct trials on a stimulus-response incompatibility task. During the first part of each trial, participants represented and maintained the instruction for that trial; during the second part, participants used the instruction either to make an automatic response or to overcome this prepotent response.


RESULTS
Behaviorally, relatives were slower when overcoming the prepotent response. Analyses focused on the first part of the trial indicated that both groups showed activity in middle frontal (Brodmann areas 46 and 9) and anterior cingulate (Brodmann area 32) gyri. However, control subjects showed significantly greater activity in dorsal prefrontal cortex (Brodmann areas 9, 8, and 6) when preparing to overcome the prepotent response, whereas patients' relatives showed prefrontal activity later, when making the response.


CONCLUSIONS
Using an event-related design showed distinct prefrontal brain abnormalities associated with the genetic diathesis to schizophrenia.
MacDonald
Angus W
AW
Department of Psychology, University of Minnesota, Minneapolis, Minnesota 55455, USA. angus@umn.edu
Becker
Theresa M
TM
Carter
Cameron S
CS
D000328:Adult; D000704:Analysis of Variance; D001931:Brain Mapping; D016022:Case-Control Studies; D003071:Cognition / Q000502:physiology*; D003072:Cognition Disorders / Q000209:etiology / Q000235:genetics*; D003463:Cues; D005190:Family; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010100:Oxygen / Q000097:blood; D017397:Prefrontal Cortex / Q000098:blood supply* / Q000503:physiopathology; D012559:Schizophrenia / Q000150:complications
D010100:Oxygen