Effects of acute alcohol consumption on alcohol-related cognitive biases in light and heavy drinkers are task-dependent.

We investigated (1) the effects of alcohol on cognitive biases for alcohol-related cues, (2) the effects of drinking status on alcohol-related cognitive biases and (3) the similarity of any effects of alcohol across two measures of alcohol cognitive bias. Healthy, heavy and light social alcohol users (n = 72) were examined in a single-blind placebo-controlled design. Participants received 0.00 g/kg, 0.13 g/kg or 0.40 g/kg of alcohol in a between-subjects design and then completed both a modified Stroop task and a visual probe task. Modified Stroop data indicated a main effect of cue type, which was qualified by drinking status, with heavier drinkers slower to respond to alcohol-related cues. Visual probe data, in contrast, indicated a significant interaction effect between validity (valid: alcohol-related, invalid: neutral) and drink condition. Participants receiving a moderate dose of alcohol (0.40 g/kg) were faster to respond to alcohol-related stimuli compared with participants receiving a low dose of alcohol or placebo. These data indicate that the cognitive processes assayed by the visual probe and Stroop tasks may not be mediated by a common underlying mechanism.