The effect of alcohol cue exposure and acute intoxication on inhibitory control processes and ad libitum alcohol consumption

Rationale: Alcohol intoxication and alcohol cue-exposure impair ‘reactive’ inhibitory control and increase motivation to drink. However, inhibitory control is a multi-component process that also comprises signal detection and proactive control. It is unknown whether intoxication and cue-exposure selectively influence these sub- processes in heavy drinkers. Objectives: In two pre-registered studies, we investigated whether exposure to alcohol-related cues (study 1) and alcohol priming (study 2) impair each of these sub-processes of inhibitory control and increase motivation to drink. Methods: In study 1, 64 heavy drinkers completed a modified stop-signal task in an alcohol context (with embedded alcohol-cues) and a neutral context (with embedded neutral-cues) followed by a subjective measure of craving and a bogus taste test to measure ad-libitum alcohol consumption. In study 2, 36 heavy drinkers consumed an alcoholic beverage (0.6 g/kg bodyweight), an alcohol-placebo beverage, and water on a within-subjects basis, followed by the modified stop-signal task and a bogus taste test. Results: In study 1, alcohol cue-exposure did not impair inhibitory control sub-processes. Reactive control was unexpectedly better following alcohol cue-exposure (compared to neutral cue-exposure). However, craving and ad-libitum consumption increased as expected. In study 2, reactive control was significantly impaired following the alcohol and control primes, relative to the placebo, but there was no effect on proactive slowing or signal detection. As expected, intoxication increased motivation to drink and ad-libitum consumption (compared to placebo and control). Conclusions: Alcohol intoxication and cue-exposure increase motivation to drink in the absence of impairments in subcomponents of inhibitory control