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

Four experiments manipulated the context in which taste-aversion conditioning occurred when the reinforcer was devalued after instrumental learning. In all experiments, rats learned to lever press in an operant conditioning chamber and then had an aversion to the food-pellet reinforcer conditioned by pairing it with lithium chloride (LiCl) in either that context or a different context. Lever pressing was then tested in extinction to assess its status as a goal-directed action. In Experiment 1, aversion conditioning in the operant conditioning chamber suppressed lever-pressing during the test, but aversion conditioning in the home cage did not. Exposure to the averted pellet in the operant conditioning chamber after conditioning in the home cage did not change this effect (Experiment 2). The same pattern was observed when the different context was a second operant-style chamber (counterbalanced), exposure to the contexts was controlled, and pellets were presented in them in the same manner (Experiment 3). The greater effect of aversion conditioning in the instrumental context was not merely due to potentiated contextual conditioning (Experiment 4). Importantly, consumption tests revealed that the aversion conditioned in the different context had transferred to the test context. Thus, when reinforcer devaluation occurred in a different context, the rats lever pressed in extinction for a reinforcer they would otherwise reject. The results suggest that animals encode contextual information about the reinforcer during instrumental learning and suggest caution in making inferences about action versus habit learning when the reinforcer is devalued in a different context. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

The rat is a common animal model used to uncover the neural underpinnings of decision making and their disruption in psychiatric illness. Here, we ask if rats can perform a decision-making task that assesses self-control by delayed gratification in the context of diminishing returns. In this task, rats could choose to press one of two levers. One lever was associated with a fixed delay (FD) schedule that delivered reward after a fixed time delay (10 s). The other lever was associated with a progressive delay (PD) schedule; the delay increased by a fixed amount of time (1 s) after each PD lever press. Rats were tested under two conditions: a reset condition where rats could reset the PD schedule back to its initial 0-s delay by pressing the FD lever and a no-reset condition in which resetting the PD schedule was unavailable. We found that rats adapted behavior within reset sessions by delaying gratification to obtain more reward in the long run. That is, they selected the FD lever with the longer delay to reset the PD delay back to zero prior to the equality point, thus achieving more reward over the course of the session. These results are consistent with other species, demonstrating that rats can also maximize the net rate of reward by selecting an option that is not immediately beneficial. Moreover, use of this task in rodents might provide insights into how the brain governs normal and abnormal behavior, as well as treatments that can improve self-control. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Given a choice, pigeons prefer an initial-link stimulus that is followed by reliable signals that food will be delivered (S+) or not (S-) after a delay, over an alternative initial-link stimulus that is followed by unreliable signals of food, even when the former yields a lower overall probability of food. This suboptimal preference has been attributed to the combination of a biased attraction to the S+ and ignoring the S-. We evaluated the inhibitory properties of the S- in three experiments to investigate its role in suboptimal choice. In Experiment 1, pigeons were trained in an autoshaping procedure with the four terminal link stimuli of the suboptimal choice task; S+ was continuously reinforced, S3 and S4 were each partially reinforced on a 50% schedule, and S- was never reinforced. Summation tests showed that S- acquired inhibitory properties during training. Experiment 2 replicated the summation tests after training on the full suboptimal choice procedure and found that S- inhibition was not attributable to external inhibition. In Experiment 3, pigeons were trained on the suboptimal choice procedure and the development of inhibition was assessed throughout training. An analysis of individual differences across birds revealed that the response rates to S- were negatively correlated with the strength of suboptimal preference, both within subject as each bird acquired suboptimal preference, and across subjects once all birds had reached asymptotic levels of suboptimal preference. Thus, rather than ignoring the S-, we found evidence that birds attended to S- as an inhibitory stimulus. Future models explaining performance in the suboptimal choice task should consider inhibition to the S- as a factor in suboptimal choice. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

We used a midsession reversal task to investigate how temporal and situational cues may combine to determine choice in frequently changing environments. Pigeons learned a simultaneous discrimination with 2 stimuli: S1 and S2. Choices of S1 were reinforced only during the first trials, and choices of S2 were reinforced only during the last trials of the session, that is, the reinforcement contingencies reversed once during the session. To weaken the temporal cue (time into the session) that signaled the reversal trial, we varied the location of reversal trial randomly across sessions; to weaken the situational cue (the outcome of the previous trials that might support a win-stay/loose shift strategy), we varied the payoff probabilities associated with S1 and S2. Performance was consistent neither with the exclusive use of a timing strategy, nor with the exclusive use of a situational, win-stay/lose-shift strategy. Instead, choice seemed to be under joint control of both cues. The relative influence of these cues was dynamic: When payoff was higher for S1 than S2, behavior was less time-controlled than when the payoff was higher for S2 that S1, or when they were equal. We advance a descriptive mixture model of joint control for the midsession reversal task. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Research on same-different categorization has shown that mastery of tasks of this kind can be strongly affected by the number of items in the training arrays-for both humans and nonhuman animals. Evidence for two-item same-different categorization in pigeons is decidedly mixed: although some investigations have succeeded, others have failed. To date, no research has documented successful conditional same-different categorization using just two items, nor has research explored how pigeons' responses in this paradigm might be influenced by perceptual characteristics of the training stimuli. Through a series of methodological modifications, we provide the first successful documentation that pigeons can perform two-item conditional same-different categorization to a high degree of accuracy; further, they can do so without the support of item repetition. We also show for the first time that the perceptual disparity between the items in pairs of different stimuli plays a key part in pigeons' same-different categorization performance. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

It has been suggested that schedule-induced behaviors allow organisms to adapt better to temporal regularities of the environment. The main goal of the present study was to observe the effect of schedule-induced drinking (SID) on the performance in fixed-interval (FI) schedules. Rats were exposed to a FI 15-, 30-, or 60-s food reinforcement schedule, and only half of them had access to water in the experimental chamber. Rats with access to water developed SID, which occurred in the first part of the interval, regardless of the FI value, and was followed by an increase in lever pressing rate. There were no substantial differences in the quantitative measures of timing between groups that had or did not have access to water, except for the rats in the FI 15-s group with access to water, who showed longer postreinforcement pauses, possibly attributable to competition between SID and lever pressing. SID did not manifest the scalar property, contrary to lever pressing, but it is proposed that behaviors are displayed serially until the last behavior before the target operant response becomes a discriminative stimulus for that behavior. It is not assumed that the purpose of schedule-induced behaviors is to aid timing, but the development of behavioral patterns might determine the performance of organisms on temporal tasks. Additionally, in some cases competition between responses might exert more control on when the operant behavior occurs than timing. Timing seems to consist in the temporal organization of available behaviors that leads to a specific behavior occurring at a specified time, a single characteristic that typically had come to indicate accurate timing. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

This special issue originally placed a Call for Papers that emphasized the importance of "Conceptual and Methodological" advances in the field of Comparative Cognition. Represented here is a collection of 14 papers that helps to display some of the diversity of ideas and approaches within this flourishing research area. The first paper in this issue, by Gazes and Lazareva (2021), discusses transitive inference learning from the perspectives of: identifying the problems of contextual variables in studying different species; whether associative processes can or cannot fully account for the behavior and, if not, what alternative representational mechanisms might be at work; and, finally, how ecological considerations may support comparative research by suggesting novel theoretical and empirical questions. The next paper, by Loy et al. (2021) investigates questions related to the complexity of learning in invertebrate species, single-celled organisms, and plants. The paper by Rawlings et al. (2021) reviews the literature on cumulative cultural evolution, primarily in nonhuman primate species, and critically evaluates the importance of identifying the essential conceptual and methodological issues in what many have deemed to be a uniquely human form of behavior. The paper by Goto and Watanabe (2021) explores whether the mouse visual system is sensitive to Gestalt principles, using operant discrimination learning tasks similar to those used previously to document Gestalt processing in chimpanzees and humans. Qadri and Cook (2021) use the innovative approach of "adaptive genetic algorithms" to assess the relative importance of different features of a stimulus in controlling organisms' discrimination learning performance. Wittek et al. (2021) introduce a novel method for studying the importance of visual accumulation processes in pigeons when information is presented to a single hemisphere at a time. The paper by Cowie et al. (2021) focuses on a misallocation model of two-step sequence learning in young children and explores from a behavioranalytic viewpoint the implications of assuming that reinforcement might be misattributed to a misremembered response at the beginning of the behavioral sequence. The paper by López-Tolsa and Pellón (2021) explores whether the opportunity to display schedule-induced drinking as an early response within a behavioral sequence might alter the accuracy of temporal control in different-length fixed-interval schedule tasks with rats. Crystal (2021) reviews the literature examining episodic memory in nonhuman species and considers a variety of criteria and methods thought to be crucial for establishing empirical evidence for episodic memory in nonhumans, in general, and rats, in particular. Vila et al. (2021) discuss the use a novel 'hide-and-seek' task in preschool age children to study episodic-like memory; their work illustrates how memory dynamics can change over time in a manner not very unlike what has been demons

Short assessments of spatial working memory (SWM) in dogs are becoming popular evaluations of canine aging and individual differences. In a typical SWM task, an experimenter hides a reward inside of a bucket at a specific stimulus position while the dog watches. Then, following a varying delay interval, the dog is released to choose a bucket. The longest delay at which the dog can successfully choose the bucket containing the reward is considered to reflect the dog's SWM duration. Although past studies were informative, the tasks often lacked a valid measure of SWM due to dogs' ability to use nonmnemonic strategies, such as body orientation or sustained attention, to successfully solve these tasks without relying on working memory mechanisms. Therefore, we designed the first study to assess the internal validity of these tasks by directly comparing dogs' performance on two experimental conditions. We found that dogs performed worse in a control condition in which nonmnemonic strategies were eliminated compared with a typical SWM task condition. In addition, our results indicate a strong relationship between the percentage of delay time that a dog spends orienting its head or body to the correct bucket and performance in a typical SWM task. These findings were the first to show a difference in SWM performance when dogs' use of nonmnemonic strategies was controlled and stress the importance of considering the internal validity of these tasks if used to examine SWM in future work. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

An innovative adaptive discrimination procedure examined how two bird species, pigeons and starlings, recognize and discriminate two-dimensional (2D) visual shapes. Prior results suggest a comparative divergence between mammals and birds in their relative reliance on vertices versus line segments to mediate discrimination. To address this potentially important difference, four pigeons and five starlings were tested with a square versus triangle discrimination in two experiments. An adaptive genetic algorithm guided the selection and organization of the training and test stimuli. Both species showed considerable flexibility in accurately selecting triangles despite wide variation in stimulus appearance and location. Most critically, Experiment 2 revealed that both bird species relied more on the figures' vertices during successful discrimination than their connecting line segments. This reliance was revealed by both traditional accuracy differences using contour-deleted displays and genetic algorithm-based shifts in "gene values" caused by the birds' selection. These results, in contrast to previous findings, indicate that mammals and birds likely converge in their reliance on vertices as a highly critical feature in visual shape discrimination. (PsycInfo Database Record (c) 2021 APA, all rights reserved).