Ethanol Preloads Increase Ethanol Preference Under Concurrent Random-Ratio Schedules in Social Drinkers

Ethanol (ETOH) preference was measured following ETOH preload doses in normal social drinkers. Eleven Ss participated in a 5-session, double-blind choice study. In Session 1, Ss sampled an ETOH beverage (0.8 g/kg). In Sessions 2-5, they consumed a preload beverage containing placebo or ETOH (0.25 or 0.5 g/kg). One hour later, they responded on 2 concurrent randomratio (RR) schedules. One schedule was associated with ETOH as the reinforcer and the other with money. When the probability of earning money was low, Ss responded more on the ETOH schedule following both ETOH preloads compared with placebo. Consistent with the increased responding for ETOH, Ss reported increased desire for ETOH. These data demonstrate a priming effect of ETOH preloads in normal social drinkers. They also illustrate the use of concurrent RR schedules to quantify ETOH preference.