This study assays memory and mood on the full range of the ascending and descending limbs of the blood alcohol curve. We monitored the effects of alcohol as people start to drink as they continue to drink, when they reach a peak blood alcohol level (about .10 g/100 ml), and during alcohol elimination. Acute tolerance to memory impairment and affective changes are being examined. Reduced performance is observed even though blood alcohol levels have returned to zero levels.