The impact of prolonging extinction on the ABC "super renewal" of instrumental responses in rats.

Two free operant conditioning experiments with rats examined the impact of conducting a large amount of extinction training on situations that enhance the ABC renewal effect (ABC super renewal). In Experiment 1, ABC renewal was strengthened by conducting acquisition in multiple contexts. All rats were trained to press a lever for food. One group was trained in one context, while the other two groups were trained in three contexts. Then, all rats received extinction in context B. For two groups this phase lasted 4 sessions, whereas it lasted 36 sessions for the other group. In Experiment 2, ABC renewal was strengthened by using a large number of acquisition sessions. Rats were trained to perform an operant response to obtain food in context A. One group received a moderate amount of training, while the rest of the rats received a larger number of acquisition sessions. Responses underwent extinction in context B. Two groups received 4 sessions, while 36 extinction sessions were used for the remaining group. In both experiments, rats were tested in context B (extinction context) and C (renewal context). Greater ABC renewal occurred both when acquisition training was conducted in multiple contexts (Experiment 1) and by increasing the amount of acquisition training (Experiment 2). Nevertheless, we found that conducting a large number of extinction sessions reduced ABC super renewal in Experiment 1 only.

Analysis of Habituation Learning in Mealworm Pupae (Tenebrio molitor).

The decline of response as a consequence of repeated stimulation is known as habituation. The goal of the present experiments was extending the knowledge about habituation of abdominal contractions in the pupa of Tenebrio molitor. Both experiments consisted of two phases. During Phase 1, all groups were exposed to a continuous stimulus (light in Experiment 1 and vibration in Experiment 2). At the beginning of this phase, pupae showed a high number of abdominal contractions. However, during the last minute of Phase 1, the number of abdominal contractions was lower. In the next phase, the pupae were divided in different groups to test for response recovery. We found an increase in the abdominal contractions when subjects were exposed to a different stimulus, be it within the same or in a distinct sensory modality. In addition, we also reported response recovery when the pupae were re-exposed to the original stimuli after a resting period. Results indicate that the increase in responding cannot be explained by either sensory adaptation or fatigue. The findings are consistent with the perspective that suggests that habituation plays a major role in the survival of the species, even in non-feeding developmental stages.

Conducting extinction in multiple contexts attenuates relapse of operant behavior in humans.

In one experiment with human participants, we investigated the effects of using multiple contexts during extinction on the renewal of operant responses. Undergraduate students played a videogame in which they learned to shoot at enemies in Context A. Then, all participants experienced an extinction training. For half of the participants, extinction trials were conducted in a single context, whereas the other half received extinction in three different contexts. Finally, all participants were tested in Context A. We observed that conducting extinction in multiple contexts attenuated ABA renewal. The present results suggest that conducting extinction in multiple contexts can be used as a behavioral technique to reduce operant renewal.

The state of transfer of stimulus control after extinction in human instrumental conditioning: A key factor in therapy strategies based in nonhuman animal research.

Previous research has shown that instrumental training can encourage the formation of binary associations between the representations of the elements present at the time of learning, that is, between the discriminative stimulus and the instrumental response (the S-R association), between the stimulus and outcome (the S-O association), and between the response and outcome (the R-O association). Studies with rats have used transfer procedures to explore the effects of discriminative extinction (i.e., extinction that is carried out in the presence of the discriminative stimuli) on these three binary associations. Thus, a reduction in the response rate of the extinguished response (R) can be detected in situations involving a different discriminative stimulus that was associated with the same outcome, and to unextinguished responses controlled by the discriminative stimulus (S) and associated with the outcome (O). These transfer effects suggest that R-O and S-O associations remain active after extinction in nonhuman animals. We carried out an experiment to explore these postextinction transfer effects in humans using a within-subject design. Contrary to nonhuman reports, the S-O association was affected by discriminative extinction, suggesting differences in the associative structure of instrumental conditioning in human and nonhuman animals that should be considered by those therapeutic strategies based in nonhuman animal research aimed to reduce unhealthy instrumental behaviours in human beings. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Preimaginal conditioning affects oviposition choices in the silkworm moth (Bombyx mori).

Nowadays we can find a number of experiments that have showed the importance of learning in several situations related with survival of many animal species. For instance, knowledge acquired in the early stages of life could be crucial on the choice of egg-laying site. In this study we explored the influence of Pavlovian conditioning of silkworm larvae on their oviposition behaviour as adult female moths. For this, the larvae learning have to survive the metamorphosis and be shown in oviposition choice. In acquisition phase, a larvae group experienced an odour (conditioned stimulus) paired with mulberry leaves (unconditioned stimulus), another one experienced the odour and the mulberry leaves in an unpaired way and the last one experienced the odour alone during this phase. The results show that when these larvae became moths, only the first group preferred to lay their eggs near the odour when it was present during the test, so that associations learned during the larval stage seem to influence oviposition behaviour during adulthood.

The reoccurrence of voluntary behavior in humans is reduced by retrieval cues from extinction.

Changes in the temporal as well as the physical context produces the reappearance of extinguished behaviors. Furthermore, combining both kinds of contextual stimuli often causes greater levels of recovery. The current experiment explored the impact of extinction reminders on spontaneous recovery, renewal, and a combination of both effects using an instrumental learning task with humans. All participants learned to shoot at enemies in a videogame. Then, throughout extinction, the instrumental response was eliminated. We found a return of the extinguished behavior by introducing a retention interval of 48 h, by changing the physical background and by testing participants in a spatiotemporal context different from the extinction context. However, we also found that the presentation of a stimulus directly associated with extinction attenuates all three forms of operant reoccurrence. These results are consistent with the perspective that emphasizes that context plays a key role in response-recovery phenomena. Moreover, our findings may be promissory for therapeutic strategies involving relapse treatment.

The Reinstatement Effect in Human Predictive Learning: Contextual Modulation and the Impact of Extinction Reminders.

One of the most relevant phenomena both from a theoretical and clinical perspective is extinction. In particular, several researchers are interested in the response recovery effects from extinction. Reinstatement is an effect that has been proposed as a laboratory model to study relapse from extinction-based therapeutic treatments. We designed two experiments with humans to evaluate the reinstatement effect in a predictive learning task. In both experiments, participants learned a specific relationship between two cues (X and Y) and two outcomes (O1 and O2) during the first phase. Throughout extinction, both cues were presented without outcomes. After an exposure to the original outcomes, reinstatement of the first-learned information was observed during testing in both experiments. However, we found that the reinstatement effect was contextual modulated (Experiment 1; ηp2 = .78, 90% CI [.48, .86], p < .0001). Furthermore, in Experiment 2 we showed a reduction of reinstatement when an extinction reminder was used ηp2 = .45, 90% CI [.07, .65], p = .012. Theoretical implications are discussed, and some potential uses are mentioned.

The role of learning in the oviposition behavior of the silkworm moth (Bombyx mori).

One of the most relevant behaviors in the life of some insects is oviposition, because reproductive fitness largely depends on the choice of egg-laying site. We report one experiment that explored the influence of Pavlovian conditioning on oviposition choices of the silkworm. Our results show that moths that jointly experienced an odor (conditioned stimulus) and mulberry leaves (the preferred oviposition place for the moths) preferred to lay their eggs near the odor when it was present, whereas moths in which the odor and the mulberry leaves never appeared together showed no preference. This result provides evidence of the important role that a psychological process such as Pavlovian conditioning has for the survival of this species.

Spacing extinction sessions as a behavioral technique for preventing relapse in an animal model of voluntary actions.

Instrumental extinction has been proposed as a model for understanding the suppression of problematic voluntary actions. Consequently, it has been suggested that response recovery after extinction could model relapse. Four experiments with rats used a free operant procedure to explore the impact of spacing extinction sessions on spontaneous recovery, renewal, reinstatement, and rapid reacquisition of extinguished lever-pressing. Initially, in all experiments, hungry rats were trained to perform two responses (R1 and R2) for food. Then, all responses underwent extinction. For R1, rats experienced a longer intersession interval (72 h) than for R2 (24 h). During the final restoration test, it was observed that using spaced extinction sessions reduced spontaneous recovery, renewal, and reinstatement. However, implementing a longer intersession interval throughout extinction exposure did not slow the rate of reacquisition of operant responses. The present findings suggest that in most cases extinction is more enduring when the extinction sessions are spaced. Since expanding the intersession interval during extinction might be interpreted as conducting extinction in multiple temporal contexts, the overall pattern of results was explained based on contextual modulation.

Reinstatement of instrumental actions in humans: Possible mechanisms and their implications to prevent it.

The study of post-extinction recovery effects in humans has received significant attention. For instance, research on reinstatement has increased in the last decade. However, most of the studies focus on the return of fear responses. In the present experiments, we used a videogame task to explore the reinstatement of operant behavior in human participants. In Experiment 1, after participants learned to shoot at enemies, they received an extinction procedure that eliminated the shooting behavior. However, the mere reintroduction of the outcome reinstated the original response. Experiment 2 showed that the reinstatement of instrumental behavior is contextually modulated. Finally, in Experiment 3 we found that presenting a reminder for extinction attenuated the response recovery effect. The overall pattern of results suggests that reinstatement of voluntary actions in humans could be explained by an interference memory framework. In addition, the present data suggest that therapies that use brief reminders of therapeutic intervention could help prevent the reinstatement of unhealthy instrumental behaviors.

Roles of context in acquisition of human instrumental learning: Implications for the understanding of the mechanisms underlying context-switch effects.

Four experiments in human instrumental learning explored the associations involving the context that develop after three trials of training on simple discriminations. Experiments 1 and 4 found a deleterious effect of switching the learning context that cannot be explained by the context-outcome binary associations commonly used to explain context-switch effects after short training in human predictive learning and in animal Pavlovian conditioning. Evidence for context-outcome (Experiment 2), context-discriminative stimulus (Experiment 3), and context-instrumental response (Experiment 4) binary associations was found within the same training paradigm, suggesting that contexts became associated with all the elements of the situation, regardless of whether those associations played a role in a specific context-switch effect detected on performance.

Reducing spontaneous recovery and reinstatement of operant performance through extinction-cues.

It has been argued that the response recovery effects share a common mechanism. A possible way to test it is evaluating whether the techniques that impaired renewal would impair the other recovery effects as well. Two experiments with rats used a free operant procedure to explore whether an extinction-cue could prevent the spontaneous recovery and reinstatement of an extinguished lever-pressing. Both experiments consisted of four phases: Acquisition, Extinction and Test 1 and Test 2. First, all rats were trained to perform one instrumental response (R1) for food in context A, and a different instrumental response (R2) for food in context B. Then, responses were extinguished within the same context: R1 in context A and R2 in context B. Throughout this phase all rats received brief presentations of a tone (extinction-cue). In both experiments animals were tested twice. The first test was conducted immediately after the last extinction session. In this test, rats received the extinction-cue for both responses. During the second test, rats experienced the tone only for R1. In Experiment 1 rats were tested after 5days, while for Experiment 2 test 2 took place after a single session of re-exposure to the food. Both experiments showed a recovery effect (spontaneous recovery in Experiment 1 and reinstatement in Experiment 2) for both responses. However, a cue featured in extinction attenuated recovery of R1 in both experiments when presented on the test. The findings suggest that spontaneous recovery, reinstatement and renewal might share a common mechanism. In addition, the present data shows that using an extinction-cue could help to reduces relapsing of voluntary behaviors.

Associative relationships in human predictive learning.

Two experiments were conducted to explore the associations involved in human predictive learning. Experiment 1 found that post-training devaluation of one of the outcomes by instructing participants that one of the attackers was indestructible, led to a significant decrease in participants' predictive responses to the cue that was initially followed by the devalued outcome, suggesting that cue-outcome associations play a major role in human simple predictive learning. In Experiment 2, immediately after receiving cue-outcome predictive judgment training, participants were instructed to destroy the attackers by using the same responses previously used to give predictive judgments, but they were not informed as to which response should be used on each attacker. During a test in which both attackers were present at the same time, when the cue was present, participants preferentially chose the instrumental response alternative that was previously used as a predictive judgment about the relationship between the present cue and its outcome. In the absence of cues, participants equally chose either response alternative. This transfer of control shows that participants also establish judgment-outcome associations during predictive training.