ABSTRACT
In a series of studies, we have documented the influence of contextual stimuli on the conditioning and extinction of taste-aversions in rats. Our general conclusion is that a contextual compound stimulus consisting of bottles, compartments and an odor element exerts strong control over postconditioning intake of the aversive substance (saccharin). The relative salience of the contextual elements has been demonstrated to be in the order of bottles > compartments > odor, and tongue-tactile bottle stimuli are likely to be the most salient. In a recent comment, Holder (1988) has raised several objections to our conclusions. His main point is that our methodology harbors a serious artifact in that the manipulations of bottle cues have been confounded by the possible influence of a “plastic” taste, emanating from the drinking bottles. In recent experiments we have shown (1) that bottle cues control both the postconditioning intake of saccharin and extinction of the saccharin aversion, and (2) that inhibitory learning of drinking spout characteristics is possible, in spite of the fact that “plastic” taste cues were controlled for. We also have data from a number of studies in which aversions to spout characteristics were produced although all the animals drank water from plastic or glass bottles. Thus, the empirical findings demonstrate that although Holder’s criticism may indeed prove to be valid if lacks substance.
