Effects of emotional context on impulse control.
High risk behaviors such as narcotic use or physical fighting can be caused by impulsive decision making in emotionally-charged situations. Improved neuroscientific understanding of how emotional context interacts with the control of impulsive behaviors may lead to advances in public policy and/or treatment approaches for high risk groups, including some high-risk adolescents or adults with poor impulse control. Inferior frontal gyrus (IFG) is an important contributor to response inhibition (behavioral impulse control). IFG also has a role in processing emotional stimuli and regulating emotional responses. The mechanism(s) whereby response inhibition processes interact with emotion processing in IFG are poorly understood. We used 4.7 T fMRI in 20 healthy young adults performing a rapid event-related emotional Go/NoGo task. This task combined the Go/NoGo task, which is a classic means of recruiting response inhibition processes, with emotionally neutral and aversive distractor images. In IFG, both response inhibition in an emotionally neutral context (neutral NoGo trials) and aversive emotional picture processing (aversive Go trials) evoked activation greater than the simple response baseline (neutral Go trials). These results are consistent with the literature. Activation for response inhibition in aversive contexts (aversive NoGo-neutral Go trials) was approximately the sum of response inhibition activation (neutral NoGo-neutral Go) and aversive emotional distractor activation (aversive Go-neutral Go). We conclude that response inhibition and aversive emotional stimulus processing activities combine additively (linearly) in IFG, rather than interfering with each other (sub-linearly) or mutually-enhancing each other (super-linearly). We also found previously undocumented interaction effects between response inhibition (NoGo vs. Go) and emotional context (aversive vs. neutral distractor pictures) in bilateral posterior middle temporal gyrus and angular gyrus, right frontal eye field, and other brain regions. These results may reflect the interaction of attention processes driven by emotional stimuli with conflict resolution processes related to Go/NoGo performance.
Dept. of Psychiatry, University of Alberta, Canada. mbrown2@ualberta.ca
Matthew R G
MR
Brown
R Marc
RM
Lebel
Florin
F
Dolcos
Alan H
AH
Wilman
Peter H
PH
Silverstone
Hannah
H
Pazderka
Esther
E
Fujiwara
T Cameron
TC
Wild
Alan M
AM
Carroll
Oleksandr
O
Hodlevskyy
Lenka
L
Zedkova
Lonnie
L
Zwaigenbaum
Angus H
AH
Thompson
Andrew J
AJ
Greenshaw
Serdar M
SM
Dursun
D000293:Adolescent; D000328:Adult; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000503:physiopathology*; D002755:Choice Behavior; D004644:Emotions; D005260:Female; D006801:Humans; D007175:Impulsive Behavior / Q000503:physiopathology*; D007266:Inhibition, Psychological; D008297:Male; D009433:Neural Inhibition; D055815:Young Adult