No abstract

Acute alcohol administration can lead to a loss of control over drinking. Several models argue that this ‘alcohol priming effect’ is mediated by the effect of alcohol on inhibitory control. Alternatively, beliefs about how alcohol affects behavioural regulation may also underlie alcohol priming and alcohol-induced inhibitory impairments. Here two studies examine the extent to which the alcohol priming effect and inhibitory impairments are moderated by beliefs regarding the effects of alcohol on the ability to control behaviour. In study 1, following a priming drink (placebo or .5g/kg of alcohol), participants were provided with bogus feedback regarding their performance on a measure of inhibitory control (stop-signal task; SST) suggesting that they had high or average self-control. However, the bogus feedback manipulation was not successful. In study 2, before a SST, participants were exposed to a neutral or experimental message suggesting acute doses of alcohol reduce the urge to drink and consumed a priming drink and this manipulation was successful. In both studies craving was assessed throughout and a bogus taste test which measured ad libitum drinking was completed. Results suggest no effect of beliefs on craving or ad lib consumption within either study. However, within study 2, participants exposed to the experimental message displayed evidence of alcohol-induced impairments of inhibitory control, while those exposed to the neutral message did not. These findings do not suggest beliefs about the effects of alcohol moderate the alcohol priming effect but do suggest beliefs may, in part, underlie the effect of alcohol on inhibitory control.

RationaleAcute ‘priming’ doses of alcohol reliably increase alcohol-seeking behaviour in social drinkers. However, the effects of the anticipated (rather than pharmacological) effects of alcohol, and their interaction with contextual alcohol cues, are not well understood.ObjectivesThis study aims to determine the extent to which an alcohol-placebo drink increases craving, subjective intoxication and beer consumption, while conjointly investigating the impact of contextual alcohol cues.MethodsOn a within-subject basis, 64 undergraduate social drinkers consumed both a placebo (which they believed to contain alcohol) and a control drink (which they knew did not contain alcohol) in different sessions. Participants completed the study procedures in a bar laboratory designed to look like a ‘pub’ or a standard psychology lab containing no alcohol-related cues. Craving (Desires for Alcohol Questionnaire) and subjective intoxication were measured pre- and post-drink, and a bogus taste test to measure ad-lib alcohol consumption was completed at the end of each session.ResultsCompared to the control drink, placebo significantly increased craving, ad-lib consumption and subjective intoxication, regardless of environmental context.ConclusionsIncreased craving and ad-lib alcohol consumption after consuming a priming dose of alcohol is at least partly attributable to the anticipated rather than the pharmacological effects of the priming dose.Electronic supplementary materialThe online version of this article (doi:10.1007/s00213-016-4518-0) contains supplementary material, which is available to authorized users.

Contemporary theories predict that Inhibitory Control (IC) can be improved when rewards are available for successfully inhibiting. In non-clinical samples empirical research has demonstrated some support, however ‘null’ findings have also been published. The aim of this meta-analysis was to clarify the magnitude of the effect of reward on IC, and identify potential moderators. Seventy-three articles (contributing k = 80 studies) were identified from Pubmed, PsychInfo and Scopus, published between 1997 – 2020, using a systematic search strategy. A random effects meta-analysis was performed on effect sizes generated from IC tasks which included rewarded and non-rewarded inhibition trials. Moderator analyses were conducted on clinical samples (vs ‘healthy controls’), task type (Go/No-Go vs Stop Signal vs Flanker vs Simon vs Stroop vs Anti-Saccade), reward type (monetary vs points vs other), and age (adults vs children). The prospect of reward for successful inhibition significantly improved IC (SMD=0.429 (95% CI= 0.288, 0.570), I2=96.7%), compared to no reward conditions/groups. This finding was robust against influential cases and outliers. The significant effect was present across all IC tasks. There was no evidence the effect was moderated by type of reward, age or clinical samples. Moderator analyses did not resolve considerable heterogeneity. Findings suggest that IC is a transient state that fluctuates in response to motivations driven by reward. Future research might examine the potential of improving inhibitory control through rewards as a behavioural intervention.