ALCOHOL TOLERANCE IN SOCIAL DRINKERS - OPERANT AND CLASSICAL-CONDITIONING EFFECTS

Four groups of males (n = 6 each) were trained on a complex psychomotor task prior to attending 5 drinking sessions. They performed the task under the same dose (0.84 ml absolute alcohol/kg) on sessions 1-4. On session 5 they received a placebo. During these sessions, the 1st group (CR) received information and a monetary reward that was contingent on the display of nonimpaired performance under alcohol. The 2nd group (IO) only received information about performance. The 3rd group (NCR) received noncontingent information and reward, administered on a predetermined schedule. The 4th group (NR) received no information or reward for performance. These manipulations were predicted to influence the order groups with respect to the rate at which tolerance developed over sessions 1-4. The findings confirmed this hypothesis, showing the rate of CR > IO > NCR > NR. The placebo session tested for the classically conditioned compensatory response unattenuated by alcohol. The strength of the response, observed as facilitated performance, was predicted and found to relate to the rate at which tolerance had developed (i.e., CR > IO > NCR > NR). This evidence for operant and classical conditioning effects in alcohol tolerance was considered to suggest that a consideration of their joint effects may be required to understand the contribution of learning to drug tolerance.