Date of Award

Winter 1980

Project Type


Program or Major


Degree Name

Doctor of Philosophy


Pavlovian conditioning has primarily employed motivationally neutral events as conditioned stimuli. Taste-aversion conditioning studies, on the other hand, use as conditioned stimuli flavored solutions with distinct motivational or response-determining properties. It is possible that many of the differences between taste-aversion conditioning and other forms of Pavlovian conditioning are related to this difference in the nature of the conditioned stimuli. This possibility was examined with regard to the nature of flavor salience in aversion conditioning. One flavor may appear more salient than another because of a difference in associability with illness, or because the more salient flavor supports a weaker, more easily disruptable consummatory response. If the second possibility is the case then the salience relations found in taste-aversion conditioning studies should correspond to the pattern of decrease in consummatory responding produced by a second, independent, rate-reducing operation. Salience relations may reflect nothing more than strength of consummatory responding for a given flavor.

In the first three experiments the correspondence between taste salience and response strength was examined. For a set of five flavors commonly employed in taste-aversion studies, consummatory response strength was assessed by measuring the decrease in consumption produced by either a water preload or hypothermic shock. In general the correspondence was strong. Stronger or less changeable responses were those typically found to be less salient in aversion-conditioning studies.

Taste salience is significantly reduced by a period of flavor preexposure. If salience is in fact determined by consummatory response strength, then flavor exposure should increase response strength. In the fourth experiment this was tested by comparing the resistance to change of consumption of a familiar or a novel casein solution. The familiar solution was shown to be associated with a far stronger consummatory response, consistent with the previous analysis.

In the final experiment bar pressing and licking were reinforced with coffee and vinegar solutions. Comparisons were then made of the pattern of suppression produced by taste-aversion conditioning, prewatering, and a conditioned suppression procedure. Agreement across the different response suppression procedures was obtained. Responding for vinegar was more suppressed than responding for coffee in all procedures and across all response measures. The correspondences in the measures of changeability suggest that flavor salience is best conceptualized in terms of the strength of consummatory responding. This interpretation, consistent with a general process approach, is shown to be able to integrate findings on flavor salience, flavor preexposure, neophobia, enhanced neophobia, extinction, and deprivation effects. It is concluded that taste-aversion conditioning may be profitably studied within the context of a general process approach.