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

In Pavlovian conditioning, the strength of a conditioned response is a function of the probability of reinforcement. However, manipulations of probability are often confounded with changes in the rate of reinforcement. Two between-group experiments in mice evaluated the effect of the probability of reinforcement, while controlling the rate of reinforcement, on appetitive conditioning and extinction. Experiment 1 equated the reinforcement rate by manipulating the number of reinforcements received in each reinforced trial in a critical group (one vs. two consecutive rewards). The results of this experiment showed that probability influenced the rate of responses in acquisition, even when controlling the reinforcement rate. Experiment 2 further assessed the role of probability on behavior while controlling the rate of reinforcement during the conditioned stimulus (CS) using a split-trial design, in which the total CS time was held constant but presented in different numbers of discrete trials (e.g., 50% reinforcement with two 12 s CS's vs. 100% reinforcement with a 24 s average CS duration). This experiment confirmed that probability influenced response rates, and both the probability and rate of reinforcement affected the proportion of trials with responses. Together, these results suggest that the probability of reinforcement, while having little effect on the speed at which responses emerged, affects responding even when the rate of reinforcement is held constant. The results challenge formal learning theories to account for the effects of both the probability and rate of reinforcement. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

The ABA renewal effect occurs when behavior is trained in one context (A), extinguished in a second context (B), and the test occurs in the training context (A). Two mechanisms that explain ABA renewal are context summation at the test and contextual modulation of extinction learning, with the former being unlikely if both contexts have a similar associative history. In two experiments, we used within-subjects designs in which participants learned to avoid a loud noise (unconditioned stimulus) signaled by discrete visual stimuli (conditioned stimuli [CSs]), by pressing the space bar on the computer keyboard. The training was conducted in two contexts, with a different pair of CSs (CS+ and CS-) trained in each context. During extinction, CS+ and CS- stimuli were presented in the alternative context from that of training, and participants were allowed to freely respond, but no loud noise was presented. Finally, all CSs were tested in both contexts, resulting in a within-subjects ABA versus ABB comparison. Across experiments, participants increased avoidance responses during training and decreased them during extinction, although Experiment 2 revealed less extinction. During the test, responding was higher when CS+ were tested in the training context (ABA) versus the extinction context (ABB), revealing the renewal of instrumental avoidance. Experiment 2 also measured expectancy after the avoidance test and revealed a remarkable similarity between avoidance responses and expectancy ratings. This study shows the renewal of instrumental avoidance in humans, and the results suggest the operation of a modulatory role for the context in renewal, similar to the occasion setting of extinction learning by the context. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Our theory of positively reinforced free-operant behavior (Perez & Dickinson, 2020) assumes that responding is controlled by two systems. One system is sensitive to the correlation between response and reinforcement rates and controls goal-directed behavior, whereas a habitual system learns by reward prediction error. We present an extension of this theory to the aversive domain that explains why free-operant avoidance responding increases with both the experienced rate of negative reinforcement and the difference between this rate and that programmed by the avoidance schedule. The theory also assumes that the habitual component is reinforced by the acquisition of aversive inhibitory properties by the feedback stimuli generated by responding, which then act as safety signals that reinforce habit performance. Our analysis suggests that the distinction between habitual and goal-directed control of rewarded behavior can also be applied to the aversive domain. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Latent inhibition is said to occur when learning about the relationship between a cue and an outcome proceeds more readily when the cue is novel relative to when the cue has been rendered familiar through mere preexposure. Previous studies suggest that latent inhibition, while evident in 4- to 5-year-old children, is attenuated or even absent in older children. There are, however, acknowledged shortcomings associated with previous demonstrations of this effect, which we attempted to overcome using a letter prediction task that has been employed in recent studies of latent inhibition in adults. One hundred and seventy-five 4- to 14-year-old children and 175 young adults completed a letter prediction task, with a latent inhibition manipulation embedded within it. Using developmental trajectory analysis we found, contrary to other studies, an increase in the magnitude of latent inhibition as children age, with the effect becoming significant when children were around 6.7 years of age. Model comparison revealed that a linear function best described the relationship between latent inhibition and age. We discuss these findings in the context of theories of learning and attention, and consider the role of concurrent task type as a factor that determines the developmental trajectory of latent inhibition. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Four experiments examined human ratings of causal effectiveness, and ability to detect causal relationships, in a nonverbal paradigm. Participants responded on a concurrent random interval, extinction schedule. In the presence of one stimulus, responses produced an outcome (triangle flash); in the presence of the other stimulus, they did not. Following making a judgment of causal effectiveness, two further stimuli were presented simultaneously with one another, and participants had to select one depending on which of the previous two stimuli were associated with effective responses. In all experiments, immediate outcomes were associated with higher causal ratings and better causal detection than outcomes delayed by 3 s. A signal inserted between response and outcome improved ratings and detection (Experiments 2 and 4), even when it was contiguous with the response but not the outcome (Experiments 2 and 3). Stimuli associated with both components (marking cues) did not impact judgments or detection (Experiment 3). Stimuli signaling the availability of an outcome if a response was made (signaled reinforcement) did not improve causal judgments, but did improve detection of stimuli associated with the outcome (Experiment 4). Responses during the delay interfered with detection of the actual relationship when delays were unsignaled (Experiments 1-4), but not with fully or briefly signaled delays (Experiments 2-4), or with signaled reinforcement (Experiment 4). The results suggest a delay stimulus serves to signal the response has been successful and demark the delay period by serving a discriminative function. These findings mirror those seen in nonhuman conditioning. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Elemental models of associative learning typically employ a common prediction-error term. Following a conditioning trial, they predict that the change in the strength of an association between a cue and an outcome is dependent upon how well the outcome was predicted. When multiple cues are present, they each contribute to that prediction. The same rule applies both to increases in associative strength during excitatory conditioning and the loss of associative strength during extinction. In five experiments using an allergy prediction task, we tested the involvement of a common error term in the extinction of causal learning. Two target cues were each paired with an outcome prior to undergoing extinction in compound either with a second excitatory cue or with a cue that had previously undergone extinction in isolation. At test, there was no difference in the causal ratings of the two target cues. Manipulations designed to bias participants toward elemental processing of cue compounds, to promote the acquisition of inhibitory associations, or to reduce generalization decrement between training and test were each without effect. These results are not consistent with common error term models of associative learning. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Neophobia and neophilia can be lifesaving as they can facilitate foraging while avoiding predation or intoxication. We investigated the extent to which Goffin's cockatoos (Cacatua goffiniana) exhibit ecollogically relevant and quantifiable neophobic responses toward specific object properties. Twelve cockatoos were presented with 12 novel objects grouped into four distinct categories with unique features: size, color, reflective capacity, and shape. The cockatoos were tested by measuring their latency to approach a high-quality food reward for both novel and control scenarios. Age and sex did not affect the latency to approach food in the presence of a novel object in this species. Additionally, we found no significant differences between the objects of the reflective and color categories. This result is likely due to the plasticity of neophobic behavior related to the benefits and costs of approaching novel stimuli. The cockatoos were significantly slower to approach food in the presence of objects larger than their body size than objects of a similar or smaller size, a phenomenon possibly explained by the increased risk of approaching unknown objects large enough to be a potential predator. They were also significantly more hesitant to approach food in the presence of elongated objects, a phenomenon potentially explained by an ecologically relevant avoidance of snakes. The extent of this neophobia was statistically similar at a group level, indicating that avoidance of elongated and large objects could be an adaptive response aiding survival under natural circumstances and that snakes may impose strong selective pressures on this species. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Taste aversion learning has sometimes been considered a specialized form of learning. In several other conditioning preparations, after a conditioned stimulus (CS) is conditioned and extinguished, reexposure to the unconditioned stimulus (US) by itself can reinstate the extinguished conditioned response. Reinstatement has been widely studied in fear and appetitive Pavlovian conditioning, as well as operant conditioning, but its status in taste aversion learning is more controversial. Six taste-aversion experiments with rats therefore sought to discover conditions that might encourage it there. The results often yielded little to no evidence of reinstatement, and we also found no evidence of concurrent recovery, a related phenomenon in which responding to a CS that has been conditioned and extinguished is restored if a second CS is separately conditioned. However, a key result was that reinstatement occurred when the conditioning procedure involved multiple closely spaced conditioning trials that could have allowed the animal to learn that a US presentation signaled or set the occasion for another trial with a US. Such a mechanism is precluded in many taste aversion experiments because they often use very few conditioning trials. Overall, the results suggest that taste aversion learning is experimentally unique, though not necessarily biologically or evolutionarily unique. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Rescorla (2000, 2001) interpreted his compound test results to show that both common and individual error terms regulate associative change such that the element of a conditioned compound with the greater prediction error undergoes greater associative change than the one with the smaller prediction error. However, it has recently been suggested that uncertainty, not prediction error, is the primary determinant of associative change in people (Spicer et al., 2020, 2022). The current experiments use the compound test in a continuous outcome allergist task to assess the role of uncertainty in associative change, using two different manipulations of uncertainty: outcome uncertainty (where participants are uncertain of the level of the outcome on a particular trial) and causal uncertainty (where participants are uncertain of the contribution of the cue to the level of the outcome). We replicate Rescorla's compound test results in the case of both associative gains (Experiment 1) and associative losses (Experiment 3) and then provide evidence for greater change to more uncertain cues in the case of associative gains (Experiments 2 and 4), but not associative losses (Experiments 3 and 5). We discuss the findings in terms of the notion of theory protection advanced by Spicer et al., and other ways of thinking about the compound test procedure, such as that proposed by Holmes et al. (2019). (PsycInfo Database Record (c) 2024 APA, all rights reserved).

According to the cycle/trial (C/T) rule, the rate of associative learning is a function of the ratio between the overall rate of U.S. presentation (C) and its rate in the presence of the conditioned stimulus (CS; [T]). This rule is well supported in studies with nonhumans. The present study was conducted to test whether it also applies to human contingency learning. In Experiment 1, participants were exposed to rapid streams of trials. Sensitivity to the cue-outcome contingency varied with both intertrial interval (ITI, which captures C) and cue duration, but the C/T rule was not respected, notably because the effect of ITI was much larger than the effect of cue duration. Experiment 2 showed that mere suppression of verbal strategies did not alter the magnitude of the ITI effect. Experiment 3 replicated Experiment 1 but with cue duration and ITI varied between 1,000 and 3,000 ms instead of between 100 and 1,000 ms. Performance was insensitive to both cue duration and ITI. This was not the consequence of Experiment 3 only varying the cue duration to ITI ratio by a factor of 3; in Experiment 4 where the cue duration was 100 ms, a 300-ms ITI was sufficient to observe an ITI effect. The lack of an ITI effect with a 1,000-ms cue and an ITI varying between 1,000 and 3,000 ms was replicated in Experiment 5. These results are discussed in light of how processes underlying associative learning might break down when events occur very rapidly. (PsycInfo Database Record (c) 2024 APA, all rights reserved).