Preliminary evaluation of a human laboratory model of impaired control over alcohol using intravenous alcohol self-administration.

Impaired control over alcohol is central to alcohol use disorder, but most research on impaired control is limited to self-report methods. This study applied intravenous alcohol self-administration to conduct a preliminary investigation of a novel human laboratory model of impaired control. Heavy episodic drinkers (ages 19-22 years) completed a two-hour intravenous alcohol self-administration session that involved an incentive to maintain breath alcohol concentration below 80 mg%. Impaired control was operationalized based on whether participants exceeded (impaired control positive; IC+) or adhered to (impaired control negative; IC-) the breath alcohol concentration limit, as well as the discrepancy between intended and actual peak breath alcohol concentration. Analyses of subjective processes revealed that IC+ participants tended to underestimate their peak breath alcohol concentration relative to IC- participants. Further, IC+ reported greater craving after an initial priming phase, and craving mediated the relationship between self-report impaired control and discrepancies between intended and actual breath alcohol concentration. IC+ participants also showed stronger within-person associations between state changes in stimulation and momentary alcohol self-administration throughout the session. Laboratory impaired control indices demonstrated convergent validity with an established self-report measure of impaired control. These findings provide preliminary validation of a novel human laboratory model of impaired control in a sample of young heavy episodic drinkers, and offer insight into the role of subjective responses (craving, stimulation) in impaired control.