Response inhibition under alcohol: effects of cognitive and motivational conflict.
OBJECTIVE
This experiment tested the effect of cognitive and motivational conflict on response inhibition under alcohol.


METHODS
Fifty-six male social drinkers were randomly assigned to one of eight groups (n = 8). Four pairs of groups received 0.62 g/kg of alcohol, or a placebo, and each pair performed a go/stop choice reaction time task under one of four conflict conditions. One condition (C) produced cognitive conflict by presenting "go" and "stop" signals in the task. Another condition (IR) added motivational conflict by administering an equal monetary reward for inhibiting responses to stop-signals, and for responding to go-signals. The remaining two conditions resolved the motivational conflict by administering the monetary reward only for inhibitions (I), or only for responses (R).


RESULTS
Compared with placebo, alcohol reduced inhibitions (i.e., impaired inhibitory control) under cognitive conflict (C; p = .041) and under motivational conflict (IR; p = .012). No significant effect of alcohol on inhibitions was observed in conditions where conflict was resolved (i.e., I and R).


CONCLUSIONS
The study shows that alcohol can reduce the ability to inhibit a response. However, impaired inhibitory control is not an inevitable outcome of the drug action, because it can be counteracted by the consequences of behavior in the situation.
Fillmore
M T
MT
Department of Psychology, University of Kentucky, Lexington 40506-0044, USA.
Vogel-Sprott
M
M
D000328:Adult; D000428:Alcohol Drinking / Q000523:psychology*; D001364:Awareness; D003220:Conflict, Psychological; D000431:Ethanol / Q000493:pharmacokinetics; D006801:Humans; D007266:Inhibition, Psychological; D008297:Male; D009042:Motivation; D011930:Reaction Time
D000431:Ethanol