DISRUPTING THE CONDITIONED-STIMULUS PREEXPOSURE EFFECT IN FLAVOR-AVERSION LEARNING - EFFECTS OF INTEROCEPTIVE DISTRACTOR MANIPULATIONS

Rats exposed to a flavor prior to a conditioning trial involving that stimulus learned a significantly diminished flavor aversion relative to nonpreexposed control Ss. Four experiments investigated the ability of the CS preexposure effect to be disrupted by the introduction of a distractor flavor stimulus between the preexposure and conditioning episodes. Exp I (39 male Sprague-Dawley rats) demonstrated that the preexposure effect could be reduced by a distractor presented immediately following the preexposure. In Exp II (55 male and female Sprague-Dawley rats), a novel distractor was more effective than a familiar distractor, even though both stimuli were sensorily equivalent. Exp III (39 male Sprague-Dawley rats) further analyzed the distractor effect and demonstrated that the magnitude of disruption was more pronounced with immediate than with delayed (3 hrs) distractor manipulations. Exp IV (8 male Holtzman rats) assessed the effects of the distractor in the absence of CS preexposure. Results are discussed in relation to general information theory. (42 ref) (PsycINFO Database Record (c) 2006 APA, all rights reserved). © 1979 American Psychological Association.