Augmentation, not blocking, in an A+/AX+ flavor-conditioning procedure

Abstract

An A+/AX+ Pavlovian conditioning design typically produces weakened or blocked conditioning to stimulus X. Two experiments were conducted in which rats first received an odor (A+) paired with an emetic US, and then received odor and taste (AX+) paired with the US. In both experiments, the preconditioned odor facilitated conditioning to the taste. In Experiment 1, a group that received two odor-illness pairings in A+ conditioning had a stronger taste aversion than a group that only had a single odor-illness pairing. Experiment 2 demonstrated that the strengthened taste aversion in the A+/AX+ condition was not due to stimulus generalization. The results represent a unique outcome in the flavor-aversion literature that is similar to potentiation. Wepropose that this facilitated conditioning to X in the A+/AX+ design be termed augmentation.

Within-compound associations mediate augmented flavor aversions

“…The first two investigations of augmentation demonstrated the ability of a preconditioned almond odor to augment responding to the bitter taste denatonium saccharide (Batsell & Batson, 1999;Batson & Batsell, 2000) whereas a later report showed that preconditioned denatonium could subsequently augment an almond odor aversion (Batsell, Paschall, Gleason, & Batson, 2001). In almost every respect, the results from these two investigations paralleled each other.…”

“…For example, in flavor-aversion learning, the pairing of a taste and an odor prior to an illness episode can result in a stronger taste aversion to the weak flavor cue; a phenomenon labeled potentiation (e.g., Rusiniak, Hankins, Garcia, & Brett, 1979). Likewise, when flavor CS A is preconditioned with an illness-producing US, and that preconditioned CS is next conditioned in compound with a new flavor cue (X), the subsequent aversion to X is not blocked, but instead, is augmented (e.g., Batson & Batsell, 2000). It is still unclear why the A+/AX+ conditioning paradigm can yield both competitive and synergistic outcomes, so identification of the mechanisms of the various phenomena may help resolve this question.…”

Trial number and compound stimuli temporal relationship as joint determinants of second-order conditioning and conditioned inhibition

“…That is, responding to a target cue can vary directly with reinforcement of its associate. Examples include potentiation (operationally identical to overshadowing; Rusiniak, Hankins, Garcia, & Brett, 1979), augmentation (operationally identical to blocking; Batson & Batsell, 2000), and second-order conditioning (operationally identical to conditioned inhibition). Moreover, posttraining extinction of the associate (A) can reduce response potential to X following potentiation, augmentation, and second-order conditioning treatments (e.g., Durlach & Rescorla, 1980).…”

A response rule for positive and negative stimulus interaction in associative learning and performance

“…Analogously, blocking (Kamin, 1968) consists of the weak response that is produced by a CS, X, when it is paired with the US in compound with a second CS, A, which was previously paired with the US on its own. In this case, based on its prior training with the US, CS A is said to block the acquisition or expression of conditioned responding by CS X. Interestingly, some studies have found a contrary effect, that is, a facilitative effect of presenting CS A on responding elicited by CS X, a result known as augmentation (e.g., Batson & Batsell, 2000).…”