Effects of component training and subsequent sequencing of stimuli on shuttlebox avoidance responding of rats

Abstract

The serial presentation of two different CSs, with each stimulus having an 8-sec duration (S1 8/S28 ) , consistently has resulted in most of the shuttlebox avoidance responses being recorded to the S2 component. Experiment 1 attempted to attenuate this serial CS, delayedresponse effect by conditioning the separate components of a serial CS prior to ordering them sequentially. Ten component-training trials were administered, with subjects receiving CS-US pairing to Sl only, S2 only, or to both Sl and S2 presented on separate trials. Two CS durations (8 or 16 sec) during this phase also were compared. Subjects were then given 100 avoidance test trials using the standard serial procedure. The 10 best avoidance responders in each group were selected for analysis. Shorter avoidance latencies were obtained only for subjects receiving component conditioning to S1. CS duration was not a factor in establishing the shorter latencies. Component conditioning to S2 resulted in increasing the total avoidances. Experiment 2 increased the number of component-training trials and the generality of the findings by using a different strain of rats and by extending the testing phase of the study so that all subjects could be included in the analysis. Comparable results were obtained. The theoretical implications of these data were discussed.In the quest to enhance our knowledge of the laws of S-R connections as they apply to complex environments, various attempts have been made to determine the functional role of individual components comprising a stimulus compound. One strategy sought to enhance the associative strength of individual components by conditioning them separately prior to combining them into a compound (Kamin, 1969;Wagner, 1971). Another approach attempted to provide a careful analysis of response topographies during training to determine whether differential responding to components could be detected (Brahlek, 1968;Levis, 1970). The intent of the present research was to determine the effects of a component-training procedure on modifying the topography of avoidance responding elicited by stimuli ordered in a serial sequence.Interest in this problem was stimulated by previous research which analyzed the effects of a Reprint requests should be sent to Donald J. Levis,