Subjective estimates of shock probability following classical aversive conditioning with visual and gustatory conditioned stimuli

Abstract

In two recent studies (Evans and Busch, 1974; Busch and Evans, in press) designed to explore the relevance of “cue appropriateness” concepts to aversion therapy, it was found that taste was a less effective CS than color. The major limitations of these studies were that conditioning was inferred from subjective ratings (although cross-validated by an unobtrusive but equally inferential performance measure), and the taste stimuli were rated more negatively in the pre-test than the color stimuli, thus creating possible ceiling effects. Quite apart from limitations in these particular studies, almost all cue appropriateness research contains methodological flaws; obvious ones are the failure to equate stimuli in different sense modalities for subjective intensity, or salience, and the failure to equate the ISIs when visual and gustatory elements of ingestible substances are the cues of interest. One of our studies (Busch and Evans, in press) partially resolved the timing problem, but in studies of visually-oriented college students the salience problem remains acute. It therefore seemed worthwhile to investigate whether, in the paradigm used in our laboratory, subjects simply attend less to taste cues than to color cues. In order to determine cue salience, a measure other than the development of CRs must be used. If an organism comes to give a CR to a certain stimulus, that is prima facie evidence of attention to, or if one prefers it, reception of, that stimulus, although generalization studies show the elements of the stimulus actually controlling the CR may not necessarily be the ones expected by the experimenter. Animal conditioning studies have shown, however, that the failure of CRs to emerge does not inevitably mean that the stimulus was ignored and an appropriate CR may appear if performance-related variables are manipulated. Similarly, humans may or may not show a CR and yet be able to verbalize correctly the contingency experienced during the conditioning. Thus for human Ss a cognitive expectancy measure should be able to reveal cue salience independent of the actual elaboration of a CR. We therefore repeated the Evans and Busch (1974) procedure and measured, instead of attitudinal changes to the CS, the Ss' perception of the contingency they had experienced.