In the individual laboratory sessions separated by at least 48 hours, participants ingested a beverage given in random order that contained a high alcohol dose (.8 g/kg alcohol) or a placebo (.0 g/kg; 1% volume of ethanol as taste mask). Another session was conducted with .4 g/kg alcohol, but this dose was subthreshold to produce subjective changes (16) and not included in this study. Doses for women were 85% of those of men to adjust for sex differences in total body water (32). To reduce alcohol expectancy, the Alternative Substance Paradigm (33) was used, with instructions that the beverage might include alcohol, a stimulant, a sedative, a placebo, or a combination of these substances. All beverages contained water, flavored drink mix, a sucralose-based sugar substitute, and the applicable dose of 190-proof ethanol. The beverage was divided into two equal portions in clear-lidded cups. Each portion was consumed within 5 minutes with a 5-minute rest interval between portions. The sessions commenced between 3:00 and 5:00 PM and proceeded for 4.5 to 5 hours in comfortable, living room–like laboratory testing rooms. Each
