Evidence for deficit in tasks of ventral, but not dorsal, prefrontal executive function as an endophenotypic marker for bipolar disorder.
BACKGROUND
Trait functional abnormalities in BD patients have only been reported in the ventral prefrontal cortex (VPFC). We examined whether deficits in VPFC-related inhibitory processes, but not dorsal prefrontal (DPFC) based executive functions, represent an endophenotypic marker for bipolar disorder I (BDI).


METHODS
We used the Wisconsin Card Sorting Test (WCST), commonly associated with DPFC function, and the Hayling Sentence Completion Task (HSCT) which engages the VPFC. Performance on these tests of 43 healthy participants was compared to that of 10 remitted BDI patients and 15 of their unaffected offspring.


RESULTS
Compared to healthy participants, patients and their offspring made more errors in the HSCT but offspring achieved more categories and made fewer perseverative errors in the WCST.


CONCLUSIONS
Impaired response inhibition, predominantly a VPFC related function, may reflect familial predisposition to BDI while deficits in rule attainment, a DPFC based function, may be associated only with the clinical phenotype.
Frangou
Sophia
S
Section of Neurobiology of Psychosis, Institute of Psychiatry, London, United Kingdom. s.frangou@iop.kcl.ac.uk
Haldane
Morgan
M
Roddy
Darren
D
Kumari
Veena
V
D000328:Adult; D001714:Bipolar Disorder / Q000175:diagnosis / Q000235:genetics* / Q000503:physiopathology*; D001931:Brain Mapping; D002648:Child; D016241:Child of Impaired Parents / Q000523:psychology*; D003072:Cognition Disorders / Q000175:diagnosis / Q000235:genetics / Q000503:physiopathology; D005260:Female; D005819:Genetic Markers; D020022:Genetic Predisposition to Disease; D006801:Humans; D007266:Inhibition, Psychological; D008297:Male; D008875:Middle Aged; D009433:Neural Inhibition / Q000502:physiology; D009483:Neuropsychological Tests / Q000706:statistics & numerical data*; D010641:Phenotype; D017397:Prefrontal Cortex / Q000503:physiopathology*
D005819:Genetic Markers