Imagery and Pavlovian Heart Rate Decelerative Conditioning

Abstract

ABSTRACTThe present experiment was designed to investigate the role of US‐imagery in Pavlovian heart rate(HR) decelerative conditioning with a head‐up to head‐down body tilt as the unconditional stimulus (US). From imagery theories of Pavlovian conditioning (e.g., King, 1973), it was hypothesized that the nature (content) of the imagery instructions would affect the conditional response (CR). Two groups of 20 subjects were employed: an Experimental (CS‐US) group and a Control (US‐CS) group. Half the subjects in each group were instructed to imagine the tilt‐US whenever the CS was presented (Relevant Imagery condition); the remaining subjects were instructed to imagine a car‐ride whenever the CS was presented (Irrelevant Imagery condition). The HR CR was assessed on a second‐by‐second basis during CS‐alone lest trials.The results of the experiment supported the hypothesis: despite an identical CS‐US contingency, only the Experimental/Relevant Imagery group (as opposed to the Experimental/Irrelevant Imagery group) demonstrated a marked, monophasic decelerative CR to the CS relative to control groups. Differences in imagery ability, instructed‐imagery vividness ratings, and US‐awareness ratings could not account for the data. The significance and implications of these findings are discussed in relation to stimulus substitution (S‐R) and cognitive (S‐S) theories of conditioning.