Alcohol expectancies and behavioral and emotional responses to placebo versus alcohol administration.

Forty normal drinking males were recruited for a study of "responses to alcohol." Following the completion of an alcohol use questionnaire that included measures of expectancies of alcohol effects, subjects were randomly assigned to either receive the actual 0.6 g/kg dose of ethanol to bring their peak blood alcohol concentration (BAC) to near 0.075 g/dl or to receive a placebo dose. Neither the subject nor the tester was aware of the condition to which the subject has been assigned. Prior to dosing and at repeated 1/2-hr intervals following dosing, subjects were tested on a battery of motor coordination, perceptual speed, reaction time, and mood measures. Significant alcohol effects were found for several measures, but the only significant interaction of individual differences in expectancies of alcohol effects with alcohol dosing occurred for self-perceived intoxication. Subjects who expected more disinhibition after alcohol dosing and who were administered alcohol reported more intoxication than those expecting less disinhibition, while no expectancy effect was found for subjects administered the placebo.