Effects of acute alcohol consumption on emotion recognition in high and low trait aggressive drinkers

Abstract

Background: Research suggests that acute alcohol consumption impairs processing of emotional faces. As emotion processing plays a key role in effective social interaction, these impairments may be one mechanism by which alcohol changes social behaviour. This study investigated the effect of individual differences on this relationship by comparing emotion recognition performance after acute alcohol consumption in individuals with high and low trait aggression.

Methods: Regular non-dependent drinkers, either high or low in trait aggression participated in a double-blind placebo-controlled experiment (N = 88, 50% high trait aggressive). Participants attended two sessions. In one they consumed an alcoholic drink (0.4 g/kg) and in the other they consumed a matched placebo. They then completed two computer-based tasks: one measured global and emotion-specific recognition performance across six primary emotions (anger, sadness, happiness, disgust, fear, surprise), the other measured processing bias of two ambiguously expressive faces (happy-angry/happy-sad).

Results: There was evidence of poorer global emotion recognition after alcohol. In addition, there was evidence of poorer sensitivity to sadness and fear after alcohol. There was also evidence for a reduced bias towards happiness following alcohol and weak evidence for an increased bias towards sadness.

Conclusions: These findings suggest that alcohol impairs global emotion recognition. They also highlight a reduced ability to detect sadness and fearful facial expressions. As sadness and fear are cues of submission and distress (i.e. function to curtail aggression), failure to successfully detect these emotions when intoxicated may increase the likelihood of aggressive responding. This coupled with a reduced bias towards seeing happiness may collectively contribute to aggressive behaviour.

Keywords: Acute alcohol consumption; emotion perception bias and sensitivity; emotional facial expressions; trait aggression.

Figure 1.

(a) Full intensity examples of the six basic emotions used in the 6AFC task. Facial expressions are angry, sad, happy, disgust, fear, surprise from left to right. (b) Fifteen-image morph sequence for the angry emotion. Stimuli range from emotionally ambiguous to full emotion intensity.

Figure 2.

Fifteen-image morph sequence used in the happy–angry 2AFC task. The images range from the full intensity example of the happy emotion along a linear continuum to the full intensity example of the angry emotion.

Figure 3.

Scores are mean proportion total hit rate scores (6AFC) in high compared with low trait aggressive individuals following both alcoholic and placebo drinks. Error bars represent standard error.

Figure 4.

Scores are emotion balance-points following alcohol and placebo drinks in high and low trait aggressive drinkers. A greater score indicates a preference for happy faces, whilst lower scores indicates a preference for angry/sad faces. Error bars are standard error.