Indices of subjective response are generally obtained through self-report, a behavior we cannot obtain directly from rodents. Nor are there obvious behavioral sequelae of feeling “high” in humans that could be examined in rodents. If “feeling effects” in humans is modeled by behaviors reflecting “reward” in rodents (e.g., selection of the drug-associated environment in a conditioned place preference test, operant responding for alcohol during extinction), there are numerous assays for rodents, but none is considered completely satisfactory in its current incarnation [see Stephens et al, this issue (Stephens et al. 2010)]. Animals can clearly recognize the subjective effects of alcohol, as it is an effective stimulus for drug discrimination studies (Barry, III 1991). However, such studies are directed at demonstrating discrimination between drugged and non-drugged states, or between the effects of one drug versus another, and not between drug state and the state following delivery of another reward.
