Effect of anticipatory stress on placebo alcohol consumption in a bar laboratory.

BACKGROUND: Only one laboratory study has examined the relation between stress and alcohol use in an ecologically valid drinking context. In that prior study, drinking was measured after the stressful situation. OBJECTIVE: To examine the effect of an anticipatory stressor, and trait social anxiety on "alcohol" consumption in a bar laboratory. METHODS: College students aged 18 and older (N = 127) in same-sex groups of two or three participants took part in a study that ostensibly examined alcohol's effect on language fluency. Using a between-subjects design, participants were randomly assigned to a stress or control condition. Participants in the stress condition anticipated giving a stressful speech for the fluency procedure, whereas those in the control group anticipated a nonstressful activity. Before the alleged fluency task, groups could order and consume mixed drinks ad lib in a bar laboratory. No beverages actually contained alcohol, but we used a validated procedure to ensure that participants included in these analyses were deceived. Primary analyses were performed with a hierarchical linear model (HLM) due to a substantial group/modeling effect. RESULTS: Counter to expectations, participants in the control group consumed more placebo alcohol than those in the stress condition. This main effect was moderated by past 3 months' drinks per week, such that the effect was attenuated (or reversed) among heavy drinkers. No main or interaction effects were observed for trait social anxiety. CONCLUSIONS: Some stressors (i.e., those invoking performance anxiety) may decrease consumption. People with higher levels of alcohol involvement might be especially motivated to drink for tension reduction purposes.

A new paradigm for credibly administering placebo alcohol to underage drinkers.

BACKGROUND: The primary goal of this study was to establish a paradigm for credibly administering placebo alcohol to underage drinkers. We also sought to create a new, valid procedure for establishing placebo alcohol believability. METHOD: Participants were 138 American college students (66.7% female) predominantly (90.0%) under the legal drinking age. Groups of 2-3 participants and one same-sex confederate consumed mixed drinks, purportedly containing alcohol, ad-lib in a naturalistic bar-laboratory for 20 min. All beverages, however, were non-alcoholic but we used visual, olfactory, and taste cues to maximize placebo credibility. Also, the confederate made two scripted statements designed to increase the perception of drinking real alcohol. After the drinking portion, participants responded to survey items related to alcohol consumption and intoxication. Next, they were individually debriefed, with open-ended responses used to make a determination of whether the participant was deceived with respect to placebo alcohol. RESULTS: All participants estimated consuming some amount of alcohol. However, using a more conservative criteria for estimating alcohol believability based on the debrief, 89.1% of participants were classified as deceived. Deceived participants were much more likely to estimate having a positive blood alcohol content and to say that their current level of intoxication was typical given the amount of alcohol consumed than non-deceived participants. DISCUSSION: Credibly administering placebo alcohol to underage drinkers is possible. This approach carries great potential for future laboratory work. In addition, the methodology used here to classify participants as deceived or not deceived appears valid based on self-reported BAC estimation and intoxication levels.

Facing temptation in the bar: counteracting the effects of self-control failure on young adults' ad libitum alcohol intake.

BACKGROUND AND AIMS: The self-control strength model suggests that exertion of self-control leads to poorer subsequent self-control performance. Failure of self-control has been suggested as an important underlying mechanism of excessive drinking. This study tested the effects of self-control failure on ad libitum drinking, and the potential moderating role of glucose and self-awareness on this relationship. DESIGN: The current research examined in two experiments whether the effects of self-control failure were different for males and females, and whether glucose (experiment 1) and self-awareness (experiment 2) would counteract the effects of self-control failure. A between-participants design with four conditions was employed in each experiment. SETTING: A semi-naturalistic drinking setting in the form of a laboratory bar. PARTICIPANTS: Undergraduate students recruited at Radboud University Nijmegen, the Netherlands (experiment 1: n = 106; experiment 2: n = 108). MEASUREMENTS: The total amount of alcohol consumed during an experimental break (observational data) and questionnaire data on drinking patterns. FINDINGS: Self-control failure led to increased levels of drinking in males (P < 0.05), whereas females drank less after being depleted (P < 0.01). Self-awareness, but not glucose, was found to counteract the effects of self-control failure among males (P < 0.05). CONCLUSIONS: Self-control failure leads to increased drinking of alcohol in males and decreased levels of drinking alcohol in females. However, increasing self-awareness appears to be a promising strategy in facing the temptation to drink when cognitive resources to inhibit intake are low.