Acute alcohol decreases performance of an instrumental response to avoid aversive consequences in social drinkers

Abstract

Background

Recent studies demonstrated that alcohol impairs inhibitory control of behavioural responses.

Aims

We questioned whether alcohol via its disinhibiting effects would also impair the inhibition of an instrumental avoidance response in the presence of a safety signal.

Design

Thirty-six moderate social drinkers were randomly allocated to receiving either alcohol (0.8 g/kg) or placebo before performing an instrumental avoidance procedure. White noise of 102 db was used as aversive outcome presented at a variable interval schedule in S+ trials, while no noise was presented in S− trials. An instrumental response (repeated space bar presses to avoid the noise presented at a variable interval) abolished the noise. The Stop Signal task and the affective Go/No-Go task were administered as inhibitory control tasks.

Results

Alcohol did not change the avoidance response rate in the presence of S− (safety signal). However, participants under alcohol performed the avoidance response to a lower extent than placebo subjects in S+ trials. Alcohol impaired performance in the Stop Signal task and increased the number of commission errors in the affective Go/No-Go task. Conditioned attentional and emotional responses to the S+ as well as knowledge of stimulus–response outcome contingencies were not affected by alcohol.

Conclusions

Acute alcohol may decrease the motivation to avoid negative consequences and thus might contribute to risky behaviour and binge drinking.