Increasing Trial Number Produces Augmentation, Not Blocking, in Flavor-Aversion Conditioning
Blocking occurs when a pre-conditioned CS (A) is conditioned in compound with a new CS (X), resulting in X being blocked thus creating a weak aversion to X. However, augmentation utilizes the same design but instead of CS A blocking learning of CS X, it actually strengthens the aversion of X. The same design, A+/ AX+, has .produced completely opposite results using basic classical conditioning. Certain parameters contribute to production of either blocking or augmentation. One parameter that has been studied is whether the compound in phase 2 has to be presented sequentially (together) or serially (one after the other). Secondly, number of trials has produced different results in basic Pavlovian conditioning. Using flavor aversion learning, two experiments using rat subjects explored flavor-aversion conditioning with the A +I AX+ design, manipulating trial number in either phase 1 or phase 2. In Experiment 1, the number of A+ trials was manipulated in phase 1 producing augmented taste aversion when odor preconditioning preceded taste + odor compound conditioning. Groups that received 2 or 4 A+ trials showed augmentation. In Experiment 2, the number of AX+ trials was manipulated in phase 2 producing augmented taste aversion when odor preconditioning preceded taste + odor compound conditioning. Groups that received 2 A+ trials, as well as either 1 or 3 AX+ trials showed augmentation. Results suggest that manipulating variables in either phase produces augmentation, not blocking.