Bilateral decrease in ventrolateral prefrontal cortex activation during motor response inhibition in mania.
Mania has been frequently associated with impaired inhibitory control. The present study aimed to identify brain functional abnormalities specifically related to motor response inhibition in mania by using event-related fMRI in combination with a Go/NoGo task designed to control for extraneous cognitive processes involved in task performance. Sixteen manic patients and 16 healthy subjects, group-matched for age and sex, were imaged while performing a warned equiprobable Go/NoGo task during event-related fMRI. Between-group differences in brain activation associated with motor response inhibition were assessed using analyses of covariance. Although no significant between-group differences in task performance accuracy were observed, patients showed significantly longer response times on Go trials. After controlling for covariates, the only brain region that differentiated the two groups during motor response inhibition was the ventrolateral prefrontal cortex (VLPFC), where activation was significantly decreased in both the right and left hemispheres in manic patients. Our data suggest that response inhibition in mania is associated with a lack of engagement of the bilateral VLPFC, which is known to play a primary role in the suppression of irrelevant responses. This result might give clues to understanding the pathophysiology of disinhibition and impulsivity that characterize mania.
Mazzola-Pomietto
Pascale
P
Institut de Neurosciences Cognitives de la Méditerranée, UMR 6193, CNRS-Université de la Méditerranée, 13402 Marseille Cedex 20, France. pascale.mazzola-pomietto@univmed.fr
Kaladjian
Arthur
A
Azorin
Jean-Michel
JM
Anton
Jean-Luc
JL
Jeanningros
Régine
R
D000328:Adult; D001714:Bipolar Disorder / Q000503:physiopathology*; D016022:Case-Control Studies; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007266:Inhibition, Psychological; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D017397:Prefrontal Cortex / Q000503:physiopathology*; D011597:Psychomotor Performance; D011930:Reaction Time; D055815:Young Adult