Harold Babb

Escape conditioning and goal punishment: Effects of acquisition trials, initial punishment trials, and CS extent

Abstract In the first of three experiments in which albino rats were given spaced shockescape trials in a straight runway, groups of 6 animals were given 6 or 24 trials followed by extinction, with or without goal-box punishment. Punishment facilitated behavior after 24 trials but did not significantly affect it after 6. Both punishment and 24 trials led to more “abrupt” extinction. In the second experiment, 6 groups of 6 animals received 6, 12, or 24 trials followed by 54 extinction trials with or without goal punishment on the first 18. All punished groups ran self-punitively, and acquisition trials effects were apparent during and after punishment. In the third experiment, buzzer extent, or duration, was manipulated, and longer extents produced stronger self-punitive effects. The results of all three experiments were interpreted in the context of presumed directive effects of aversive and conditioned aversive stimuli.

Effects of percentage of goal-punished extinction trials on self-punitive behavior

Following 20 shock-escape acquisition trials in a straight runway, 36 female albino rats were given.5-sec shock after entering the goalbox on 0%, 20%, 40%, 60%, 80%, or 100% of extinction trials. Relative to the 0% controls, all punished groups ran significantly faster during extinction but did not differ significantly among themselves. The results confirm earlier studies demonstrating self-punitive behavior using the goal-shock procedure and are consistent with other research in which intermittent punishment has been applied in the alley. Nevertheless, the results do not seem to be supportive of theoretical points of view that stress the critical importance of maintaining the eliciting stimuli and the reinforcing conditions that were present during acquisition.

Facilitation by Goal Punishment After Escape Conditioning: CS Intensity Effects

The intensity of a buzzer conditioned stimulus (CS) was manipulated during shock-escape conditioning and extinction of albino rats in a straight runway, using a guillotine-door procedure. After 20 acquisition trials, the rats were placed on extinction, but half were given regular extinction trials and half were subjected to shock punishment in the goal box at the termination of each run. The CS conditions of no buzzer, 71-dB buzzer, and 83- dB buzzer had no significant effects during acquisition, and they did not differentiate punished groups during extinction. Nevertheless, the higher intensity buzzer produced faster running on the part of nonpunished animals during extinction than did the no buzzer condition. In contrast to certain theoretical positions, punishment facilitated running under all CS conditions. The results were interpreted as a function of the differential presence of conditioned aversive stimulation with reference to the rat’s presence in different parts of the apparatus.

Goal vs. alley punishment after escape training: Massed trials and startbox conditions

Two different starting procedures, drop box vs. guillotine door, were used in giving 36 male rats 20 massed shock-escape trials in a straight runway. On subsequent trials, the animals encountered no shock at all, shock punishment in the middle 2 ft of the 4-ft alley, or shock for.5 sec immediately after entering the goalbox. The guillotine-door procedure produced faster running in extinction, alley punishment facilitated responding, and goal punishment sup- pressed responding. Results were interpreted in terms of stimulus-directive effects, as modified by massing vs. spacing trials.

Self-punitive behavior: Effects of number of massed acquisition trials and percentage of goal-shocked extinction trials

Using a massed trials procedure, rats were given 6, 12, or 24 shock escape acquisition trials in a runway, followed by extinction in which they received no further shock anywhere in the alley, or shock in the goalbox on 0%, 10%, or 100% of extinction trials. Results indicate that number of acquisition trials had no effect on run or start speeds during extinction. Percentage of shocked extinction trials did, however, affect extinction performance measures. In comparison with nonshocked controls, animals shocked on 10% of trials showed facilitation of extinction response measures. Extinction response measures for animals not shocked or shocked on 100% of trials were similar. The results further clarify what variables affect goal-shock-induced facilitation of extinction performance, and are discussed in the context of current theoretical interpretations of self-punitive behavior.

Transfer suppression of a hunger-motivated response as a function of the number of prior escape or avoidance trials

Several prior studies have demonstrated suppression of an appetitively motivated response (relative to controls) acquired on the basis of prior aversive motivation. These studies used a small number of escape-acquisition trials prior to transferring a runway response across drive-reinforcement conditions. The present study was an attempt to determine if an avoidance procedure, as well as an escape procedure, in the aversive phase, would produce suppression in transferring to hunger-motivated responding. It also constituted an effort to determine the influence of extended aversive training on the degree of suppression. Four experimental groups of rats were used in a 2 by 2 factorial study (aversive condition: escape or avoidance by number of aversive trials: 15 or 45). Each group was subsequently food deprived and transferred to hunger-motivated responding in the same runway. The experimental groups started and rail at about the same suppressed speeds, relative to a hunger-motivated control group given no prior aversive training. These results replicate the basic suppression effect and extend it to animals given prolonged aversive training. Further, the effect is demonstrable with prior avoidance as well as with prior escape training. Possible explanations of suppression are presented.

Goal aversiveness after escape training with short and long intertrial intervals

Different intertriai intervals (ITIs) may influence the aversiveness of the goal area in aversive training with one-way procedures. That possibility was explored. Albino rats were given 20 shock-escape runway trials with short or long ITIs followed by 5 extinction test trials with goalbox measures for latency to eat, climb out, and move onto a wood floor. Different measures produced different outcomes. “Time to eat” did not differentiate groups. Massed-trials animals were quicker to “move over” initially but slowed down over trials. Spaced and massed procedures did not produce initial differences on “climb out,” but spaced-trials animals speeded up over trials and massed-trials animals slowed down. Results suggested that differences in ITIs did not generate major differences in levels of aversion in the “safe” area. ITI effects on performance may be due to differential effects on the conditioning process.

Response compatibility in transfer from aversive to appetitive training

In transfer from shock escape to appetitively motivated training in a straight runway, 64 male hooded rats were given various pretreatments, or none, prior to transfer. With appropriate controls, running was motivated by high-intensity noise (120 dB) or shock (1 mA), by low-intensity shock (.2 mA), or by a second-order aversive excitatory stimulus prior to the elimination of those stimulus conditions and the initiation of food reinforcement. In general, all of the pretreatments produced extended suppression in the transfer condition. Controls for latent inhibition indicated none was present. High-intensity shock reduced eating on initial food reinforcement trials, but the other aversive conditions did not. The results were interpreted as possible consequences of stimulus-directive effects.