Assessing the stimulant and sedative effects of alcohol with explicit and implicit measures in a balanced placebo...

Alcohol consumption is characterized by bi-phasic stimulant and sedative effects. In previous studies, various tools were used to assess these effects, including expectancy questionnaires, implicit association tests, and self-report scales. The present study was aimed at clarifying the relationships between these measures.

Three different measures were used to directly or indirectly assess the stimulant and sedative effects of alcohol in 61 undergraduate students. The participants completed the Alcohol Expectancy Questionnaire (AEQ) and performed two unipolar Implicit Association Tasks to assess implicit associations between alcohol and the concepts of "stimulation" and "sedation." The levels of alcohol consumption also were recorded by means of the Alcohol Use Disorders Identification Test. An alcohol (0.4 g/kg) or placebo challenge was then administered using a balanced placebo design. After alcohol/placebo administration, the participants completed the Biphasic Alcohol Effects Scale (BAES).

Alcohol consumption significantly correlated with AEQ alcohol explicit expectancies of arousal and relaxation, whereas no significant correlations were obtained with the implicit associations. There were positive correlations between AEQ and BAES subscales, especially for the arousal subscale of the AEQ. Self-reported sedation recorded with the BAES was significantly affected by what the participants believed that they had drunk but not by the actual consumption of alcohol.

These findings indicate that alcohol explicit expectancies of arousal measured with the AEQ best predict current alcohol consumption. Regarding explicit measures of alcohol-induced stimulation and sedation, BAES sub-scales seem to be more affected by alcohol drinking expectations than by actual alcohol consumption.