Residual fear of the conditioned stimulus as a function of response prevention after avoidance or classical defensive conditioning in the rat.

Abstract

Studies employing response prevention (RP) are reviewed. Considering assessment difficulties and conflicting findings, it is questionable whether RP actually reduces fear to a conditioned stimulus (CS). This study measured fear after RP via a conditioned emotional response (CER) paradigm. Hypotheses were that fear of an auditory CS (conditioned in an avoidance paradigm) is reduced during RP, and that fear conditioning would occur to aspects of the conditioning environment per se. Also evaluated was the effectiveness of RP when fear had been learned under two different conditions: (a) avoidance or (b) classical defensive conditioning. Seven groups of 10 experimentally naive female rats were run. Animals were initially trained to bar press for food pellets on a variable interval (VI) 2 schedule. Three groups were then avoidance trained in a two-way shuttle box to a criterion of 10 successive avoidances. Immediately following acquisition, one group received RP (blocking) in the shuttle box (Condition A-B). This consisted of placing a door between the two sides of the box and presenting the 85 dB (A) white noise CS for 15 20-sec periods with a variable 1-min interstimulus interval. One group did not receive RP (nonblocked) and was instead immediately returned to its home cage (Condition A-NBHC). The third group was treated as was A-B except the CS was not presented (Condition A-NBSB). Two other groups were trained in a classical defensive paradigm. These animals were matched to A-B animals in terms of number, order, and duration of CSs and USs. Following conditioning, one group received the same treatment as A-B (Condition CD-B), and the other received the same treatment as A-NBHC (Condition CD-NBHC). Two groups served as controls. A backward control (Condition BC-NBHC) was matched to A-NBHC in terms of number, order, and duration of CSs and USs. A sensitization control (Condition SC-NBHC) was matched to A-NBHC in terms of number, order, and duration of CS presentations. Immediately following conditioning trials, control animals received the same treatment as A-NBHC animals. After differential treatments all animals were immediately returned to the lever box in which they had learned to bar press, a VI 2 schedule was reinstated, and the CER was measured. A-B showed significant suppression initially but significantly less than A-NBHC, suggesting that although RP was effective in reducing fear to the CS, some fear remained. Controls showed essentially no suppression and did not differ. A-B did not differ from A-NBSB, suggesting that conditioning of fear did occur to the environment and that this fear was subsequently reduced in A-NBSB. A-B suppressed significantly more than CD-B, suggesting that RP was more effective when fear was learned in a classical as compared to an avoidance paradigm. Theoretical implications and generalizations to implosive therapy are discussed.

The effect of number and minimum duration of post-response-prevention escapes on the resistance to extinction of an avoidance response

“…Therefore, the difference in extinction responding when post-response-prevention escapes were provided was presumably due to the increased aversiveness of the CS resulting from Pavlovian conditioning for Group CS-US and to the decreased aversiveness of the CS resulting from Pavlovian extinction during response prevention for Group CS-only (cf. Bersh & Paynter, 1972;Monti & Smith, 1976). The fact that 10 unrestricted or 5 restricted escapes failed to increase extinction responding for CS-US animals indicates that the combination of further light-shock exposures and/or negative reinforcements was inadequate to enhance the effect of the already high level of CS aversiveness produced by Pavlovian conditioning during response prevention.…”

“…However, the basis for the effectiveness of avoidance-response-prevention procedures is controversial (Baum, 1970;Mineka, 1979). Although several theoretical accounts have been proposed, the effect of avoidance-response prevention in reducing the subsequent resistance to extinction of avoidance behavior is commonly ascribed to the development of competing behavior (Coulter et al, 1969;Linton, Riccio, Rohrbaugh, & Page, 1970;Page, 1955) and/or to a reduction in the aversiveness of the warning signal resulting from its presentation without shock during response prevention, that is, Pavlovian extinction (Bersh & Paynter, 1972;Corriveau & Smith, 1978;Monti & Smith, 1976). Empirical evidence favoring the competing response theories has largely been…”

Repeated exposure of naïve and peripheral nerve-injured mice to a snake as an experimental model of post-traumatic stress disorder and its co-morbidity with neuropathic pain

“…Additionally, in PTSD, the emotional response pattern appears to show some degree of generalisation to different stimuli strongly associated with the traumatic experience or even with mild stressor stimuli not primarily associated with the trauma, and exacerbated responsiveness displayed by PTSD patients persists to the traumatic event itself (Monti and Smith, 1976;Morey et al, 2015;Osborne et al, 1975). Accordingly, snake exposure reduced time spent in the open-arm of the EPM test, an environment not associated to the previous aversive place, the enriched polygonal arena for snakes, where psychologically traumatic emotions were experienced by prey in the presence of the wild snake.…”

A comparison of response prevention and massed-trials extinction in deconditioning avoidance

“…As in Baum and Oler (1968) apparatus cues served as the CS (see also Corriveau & Smith, 1978;Monti & Smith, 1976). Since withdrawal of the ledge consequently slightly altered the CS complex in response prevention, a second Response Prevention vs. Massed Trials 201 response prevention group (RP-2) was run as a comparison, in which the ledge was not withdrawn, but was made inaccessibls by the insertion of a perspex slide.…”