THE TASTE OF ALCOHOL FOR RATS AS REVEALED BY AVERSION GENERALIZATION TESTS

In six experiments, naive rats were trained to avoid alcohol by pairing its presentation with lithium chloride-induced illness. Rats were then tested for aversion generalization by presenting various test solutions. Rats trained to avoid either 3, 6 or 9% (v/v) alcohol generalized the aversion to a sucrose + quinine hydrochloride solution. The five remaining binary combinations of sucrose, sodium chloride, hydrochloric acid and quinine hydrochloride failed to produce significant generalization in trained rats (Experiment 1). In further experiments, rats trained to avoid 6% alcohol showed significant aversion generalization to a variety of sucrose + other 'bitter' solutions (Experiment 2) and sucrose + acid solutions (Experiment 3). Varying the concentration of hydrochloric acid in a sucrose + acid mixture produced small but uniform degrees of aversion generalization (Experiment 4). Rats trained to avoid 6% alcohol did not generalize the aversion to sucrose alone, regardless of concentration (Experiment 5). Finally, in Experiment 6, rats trained to avoid 6% alcohol suppressed consumption over a range of alcohol concentrations. These results confirm that, for rats, the taste of alcohol has a complex set of characteristics; sweet taste in combination with other tastes appears to be the most similar as it is to these solutions that rats with alcohol aversions show the most generalized avoidance.