Establishment of conditioned taste aversions with a 24-hour CS-US interval

Abstract

Two experiments were conducted investigating the effects of a 24-h CS-US interval in taste aversion learning. In the first experiment, male albino rats were allowed to consume a nonpreferred CS (HCL-flavored water) and injected, intraperitoneally, 24 h later with an illness-inducing drug (cyclophosphamide). After two such pairings, the animals exhibited an aversion to the flavored water. In Experiment II, female rats were exposed to the same US 24 h following consumption of a preferred CS (saccharin-flavored water). However, after only one such pairing, experimental Ss avoided the flavored water and preferred normal tap water in a two-bottle choice situation, while saline-injected controls preferred the saccharin-flavored water to the plain tap water. Due to the controversial nature of conditioning with such long delays of reinforcement, a systematic replication of Experiment II was conducted with male rats, and again an aversion was established to the saccharin-flavored water. © 1973, Psychonomic Society, Inc.. All rights reserved.