Journal of Experimental Psychology-Animal Learning and Cognition最新文献

In a typical feature-positive discrimination, responding is reinforced (+) during the target stimulus (A) on trials with the feature stimulus (X), but not during target-alone trials (A-). When X and A are presented simultaneously, direct control by X is typically observed; however, when the stimuli are presented serially, X sets the occasion for responding to A. In the current dual-response procedures, one response (e.g., left lever press) was reinforced during feature-target trials (XA+) and a different response (e.g., right lever press) was reinforced during target-alone trials (A+). In Experiment 1, rats received either serial (X → A+) or simultaneous (X:A+) presentations of the feature-target compound along with target-alone trials (A+). Contrary to our predictions, the serial group failed to learn the discrimination and the simultaneous group demonstrated occasion setting. In Experiment 2, the salience of the feature was increased, which resulted in direct control by the feature in both groups. In Experiment 3, an additional serial group was included with a longer interval between the feature (X) and target (A). Despite the reduced temporal proximity of X to reinforcement, direct control was again observed in all groups. The current pattern of results in the simultaneous and serial groups is interpreted in relation to the enhanced salience of A relative to X, due to separate pairings of A-alone with reinforcement in the dual-response procedure. Consistent with previous findings, occasion setting was observed when A was most salient relative to X (Experiment 1, simultaneous group), but direct control was found when the salience of X was increased (Experiments 2-3). (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Three experiments with rats explored whether previously extinguished goal-directed and habitual responding recover with the same status using an ABA renewal preparation. In Experiments 1a and 1b, a lever-press response was minimally (four sessions) or extensively (16 sessions) trained in one context (Context A) and extinguished in another context (Context B). Then, outcome devaluation took place in either Context A or Context B in which a food pellet reinforcing the response was paired with lithium chloride (LiCl) for devalued groups and with saline for a control group. Finally, renewal of the extinguished response was tested in both Contexts A and B. We confirmed that both minimally and extensively trained responses renewed as goal-directed action regardless of the context in which devaluation took place. This finding was replicated in Experiment 2 even after more extended acquisition training (32 sessions). However, another group that received outcome devaluation before but not after extinction training showed habitual performance during extinction training as well as in a subsequent renewal test. Experiment 3 replicated these results and confirmed that renewal of goal direction for rats that received extinction training immediately prior to outcome devaluation was not an artifact of consecutive LiCl exposures over a short period of time in Experiments 1 and 2, using a more reliable devaluation protocol. Overall, the present results extend previous findings suggesting that actions and habits renew with the same status by returning to the original context after extinction. The most critical finding is the differential effects of pre- and postextinction devaluation on the expression of habitual behavior; extinction prior to devaluation may convert a habitual performance into a goal-directed action. This novel finding is discussed in relation to recent studies that identified several factors contributing to a transition from habitual to goal-directed control of instrumental behavior. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

In situations in which multiple predictors anticipate the presence or absence of an outcome, cues compete to anticipate the outcome, resulting in a loss of associative strength compared to control conditions without additional cues. Critically, there are multiple factors modulating the magnitude and direction of such competition, although in some scenarios the effect of these factors remains unexplored. We sought to assess whether the relative salience of the elements in a compound of cues modulates the magnitude of the overshadowing effect in human predictive learning. Two separable categories (i.e., colors and symbols) were used in a predictive learning task. In Experiment 1, different groups of participants were granted with different time of exposure to a compound of cues belonging to different categories (color and symbol) to evaluate potential differences in the magnitude of overshadowing. Furthermore, we used posttest questionnaires to assess whether participants used either only one or both categories during training, and assessed if this impacted the magnitude of overshadowing. In general, overshadowing was not modulated by the time of exposition, except in the case of very short time of exposition with prominent learning about the most salient category. In Experiment 2, the relative salience of a category was biased via prior experience either with a biconditional discrimination or attending only the relevant category (either color or symbol). The previously relevant category was less prone to overshadowing, but not the alternative one. Results are discussed in light of attentional and configural theories of associative learning. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Three experiments explored how training reinforcement schedules and context influence the elimination and recovery of human operant behavior. In Experiment 1, participants learned a discriminated operant response in Context A before the response was eliminated with extinction in Context B. They then received a final test in each context. Groups were trained with a discriminative stimulus that predicted a reinforced response on either every trial (continuous reinforcement [CRF]) or some of the trials (partial reinforcement [PRF]). Extinction was slower following PRF training (a partial reinforcement extinction effect [PREE]) and extinguished responding increased when tested in Context A ("ABA" renewal). Experiment 2 further confirmed the PREE was obtained equally whether extinction occurred in the training context (Context A) or a new context (Context B) which is consistent with trial-based accounts of the PREE. Experiment 3 used the same design as Experiment 1 to evaluate the influence of training reinforcement on response elimination with an omission contingency. Across the omission training phase in Context B, the decrease in responding occurred more slowly in the PRF-trained group in comparison to the CRF-trained group, perhaps the first demonstration of what might be termed a PRF omission effect. Again, ABA renewal was observed in Context A. Training reinforcement schedule therefore had a similar influence on response elimination with extinction and omission. Elimination and recovery of human instrumental behavior, with extinction or omission, are influenced by training reinforcement schedule and context. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Intermixed exposure to two similar stimuli, for example, AX and BX, improves subsequent discrimination between them compared to blocked exposure (the intermixed/blocked effect). Salience modulation models, developed mainly from research with nonhuman animals and exposure to widely spaced similar stimuli, explain this effect in terms of increased salience of the unique elements, A and B. Conversely, the results from experiments initially conducted with humans and exposure to close spaced similar stimuli have led to the suggestion that it is the development of well-unitized representations of unique elements that leads to better discrimination, leaving the unique elements with less effective salience. The experiments carried out here aim to replicate the intermixed/blocked effect in rats using an exposure procedure with rapid succession between stimuli and to assess the effective salience of unique elements. In Experiment 1, an aversion to a new flavor, Y, was conditioned and then an external inhibition test with AY was given. In Experiment 2, an aversion to A was conditioned and its extinction was measured on unreinforced trials. In Experiment 3, an aversion to AY was conditioned and the associated aversion to Y was measured. We found after rapid intermixed preexposure a reduction in generalization from the aversive Y element to the compound AY (Experiment 1) as well as a reduction in A's salience (Experiments 2 and 3) compared to the effects of blocked preexposure. The results are discussed in terms of the various mechanisms underlying perceptual learning, which appear to depend on the details of the task. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

We report here two large studies investigating the effects of an established transcranial direct current stimulation (tDCS) procedure on perceptual learning as indexed by the face inversion effect. Experiments 1a and 1b (n = 128) examined the harmful generalization from Thatcherized faces to normal faces by directly comparing the size of the inversion effect for normal faces when presented intermixed with Thatcherized faces (Experiment 1a) versus that obtained when normal faces were presented intermixed with checkerboards (Experiment 1b). The results from the sham/control tDCS groups provide the first direct evidence in the literature showing how Thatcherized faces generalize onto normal ones producing a reduced inversion effect compared to when normal faces are presented with stimuli (e.g., checkerboards) that do not generalize significantly to normal faces. In the anodal tDCS groups, this effect was reversed, with a larger inversion effect recorded for normal faces in Experiment 1a versus that found in Experiment 1b. Further analyses within each experiment confirmed that the anodal tDCS procedure can enhance the inversion effect for normal faces in circumstances where harmful generalization would otherwise be produced by the Thatcherized faces (Experiment 1a). We also demonstrated our standard reduction in the inversion effect for normal faces consequent on the application of tDCS when presented intermixed with stimuli that do not generalize onto them. We interpret our results in terms of simulations using the MKM model of perceptual and associative learning. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

In three experiments, rats were given experience of flavored solutions AX and BX, where A and B represent distinctive flavors and X a flavor common to both solutions. In one condition, AX and BX were presented on the same trial separated by a 5-min interval (intermixed preexposure). In another condition, each daily trial consisted of presentations of only AX or only BX (blocked preexposure). The properties acquired by stimulus X were then tested. Experiment 1 showed that after intermixed preexposure X was less able to interfere with a conditioned response established to a different flavor. Experiment 2 showed that X was less effective at overshadowing when trained in compound with another flavor. Simple conditioning, with X as the conditioned stimulus, was not sensitive to the form of preexposure (Experiment 3). These results indicate that the opportunity to compare similar stimuli that is provided by presenting them in close succession can change the properties of features they hold in common, making these features less effective when tested in compound with other stimuli. A loss of effectiveness by such features would contribute to the perceptual learning effect, the enhancement of subsequent discrimination, that is generated by prior exposure to closely spaced similar stimuli. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Four experiments explored the impact of focused-attention mindfulness training on human performance on free-operant schedules of reinforcement. In each experiment, human participants responded on a multiple random ratio (RR), random interval (RI) schedule. In all experiments, responding was higher on RR than RI schedules, despite equated rates of reinforcement. A 10-min focused-attention mindfulness intervention (focused attention) produced greater differentiation between schedules than relaxation training (Experiments 1, 2, and 4), or no intervention (Experiment 3). Focused-attention mindfulness improved learning when the schedules associated with components of the multiple schedule were reversed. This occurred irrespective of whether the focused-attention mindfulness was before (Experiment 2) or after (Experiments 3 and 4) initial training, or whether compared to relaxation (Experiments 2 and 4) or no intervention (Experiment 3). In Experiment 4, following multiple RR, RI training, focused-attention mindfulness increased sensitivity to contingency reversal and did not interfere with previous training in a group that did not receive a contingency reversal. In contrast, relaxation training did not facilitate reversal learning and interfered with previous learning. The results suggest that focused-attention mindfulness improves awareness of operative contingencies by focusing participants on the present, rather than reducing interference from previous learning. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Inhibitory stimuli are slow to acquire excitatory properties when paired with the outcome in a retardation test. However, this pattern is also seen after simple nonreinforced exposure: latent inhibition. It is commonly assumed that retardation would be stronger for a conditioned inhibitor than for a latent inhibitor, but there is surprisingly little empirical evidence comparing the two in either animals or humans. Thus, retardation after inhibitory training could in principle be attributable entirely to latent inhibition. We directly compared the speed of excitatory acquisition after conditioned inhibition and matched latent inhibition training in human causal learning. Conditioned inhibition training produced stronger transfer in a summation test, but the two conditions did not differ substantially in a retardation test. We offer two explanations for this dissociation. One is that learned predictiveness attenuated the latent inhibition that otherwise would have occurred during conditioned inhibition training, so that retardation in that condition was primarily due to inhibition. The second explanation is that inhibitory learning in these experiments was hierarchical in nature, similar to negative occasion-setting. By this account, the conditioned inhibitor was able to negatively modulate the test excitor in a summation test, but was no more retarded than a latent inhibitor in its ability to form a direct association with the outcome. (PsycInfo Database Record (c) 2023 APA, all rights reserved).