In social foraging situations, some group members actively engage in behaviors associated with searching for patch zones (produce), while others join previously discovered patch zones (scrounge). Pavlovian conditioning enables individuals to anticipate a biologically significant event or unconditioned stimulus, such as resource availability, when paired with another event, such as a blue light, also known as a conditioned stimulus (CS). Considering that individuals' prior experiences with habitat features may influence their preference for producer or scrounger responses, this study aims to assess the impact of resource-associated signals on the group produce index. Specifically, the study seeks to (a) outline a setup for goldfish () incorporating renewable patch zones, (b) evaluate the CS's effect on the proportion of producers, and (c) develop an agent-based model capturing the CS's effect on the proportion of producers. Eight goldfish were used, with half undergoing a delayed Pavlovian acquisition protocol. Pavlovian-trained and control fish were assessed under signal and nonsignal conditions. The findings reveal that the producer index in the signal condition was higher for the Pavlovian group than the control group. To simulate conditions to those observed in fish, we developed an agent-based model where Pavlovian agents oriented themselves toward the nearest patch zone when the CS was present. The results mirrored those observed in fish, indicating an advantage derived from preexposure to the CS. This study contributes to the investigation of individual disparities and the impact of learning within the framework of the producer-scrounger game. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Song sessions produced by humpback whales recorded off the coasts of Hawaii and Colombia show recurrent patterns of acoustic variation across consecutive songs. Analyses of intra-individual variations within continuous song sessions revealed that songs consistently cycled through stages of acoustic complexity. At time scales spanning tens of minutes, cyclical variations likely reflected the diving behavior of singers. Changes over shorter time frames suggest that singing humpback whales may also systematically modulate the acoustic complexity of individual sounds during song production, both by gradually morphing units and by varying the number of times they repeat sound patterns. Comparable cycles were evident across years and populations. Cyclical variations within song sessions can reveal how much time and energy singers spend producing tonal versus frequency-modulated/broadband elements. Tonal components are generally more difficult to localize spatially but easier to detect over long distances, suggesting that singing humpback whales may dynamically vary sound production in ways that affect both sound transmission and auditory spatial processing. (PsycInfo Database Record (c) 2025 APA, all rights reserved).

Decreasing responsiveness to repeated visual stimuli (i.e., the inability to sustain attention) in jumping spiders (Salticidae) parallels that found in humans. In humans, drugs affect vigilance, and previous work on salticids has shown that the "vigilance decrement" is unlikely to be sensory habituation and that caffeine ameliorates reductions in attention. We exposed to delta-9 tetrahydrocannabinol (THC) and methamphetamine before presenting them with a repeated visual stimulus. In the THC experiment, spiders were given a THC solution, water, or a vehicle solution, using a within-subjects design. The orienting response (i.e., "interest") of salticids on a track ball to face a fly stimulus presented peripherally on a monitor was scored, as well as "general movement" (e.g., walking, as a control for physical fatigue) and "no movement." The methamphetamine experiment was identical except that salticids were given methamphetamine solution or water. In both the THC and methamphetamine treatments, general movement dropped over time, while in control treatments, this was constant. Additionally, due to an initial stimulating effect of methamphetamine on interest, the response decrement was significantly steeper when spiders were administered methamphetamine compared with water. Our results suggest that the modulation of sustained attention, and possibly motivation, is likely in salticids. basic local alignment search tool genome queries on a closely related species and pharmacological radioligand experiments suggested that salticids do not possess cannabinoid receptors, but the presence of transient receptor potential proteins may help explain the small behavioral changes observed with THC. In contrast, how methamphetamine affects salticids remains unknown. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

The featured article by Sakurai and Tomonaga (2024) in this issue has set out to test to what extent dolphins can estimate relative differences between pairs of object numbers by echolocation. For this they used three consecutive experiments with multiple controls and compared their data statistically to existing data from visual experiments done on other species. Previous studies already indicate that dolphins can visually estimate relative numerosity (e.g., Jaakkola et al., 2005; Yaman et al., 2012). Therefore, the goal of the present study was to investigate the dolphin's capacity to apply Weber's law (quantity judgments are more accurate proportional to the quantities investigated) to two sets of object quantities under sonar evaluation. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Organisms are believed to attempt to maximize their net energy intake while foraging. The paradoxical choice task shows that they may instead prefer to obtain information rather than primary reward when the outcome is uncertain. That is, they prefer stimuli that consistently predict food or no food (informative option), to stimuli that inconsistently predict both food and no food in larger amounts (noninformative option). This task also seems to indicate that some species (like pigeons, and starlings, ) are more prone to choose the informative option, while other species (like rats, , and humans, ) tend to favor reward procurement through the noninformative option. There is empirical evidence for and against this view. However, an analysis of the literature suggests that species differences in paradoxical choice might be less pronounced than often believed. We argue that pigeons and rats are usually not tested under conditions that are motivationally equivalent for both species-in particular, the opportunities to track consistent stimulus-food pairings are less often met in the rat studies than in the pigeon studies. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Understanding conspecifics' age classes is crucial for animals, facilitating adaptive behavioral responses to their social environment. This may include gathering and integrating information through multiple modalities. Using a cross-modal preferential-looking paradigm, we investigated whether dogs possess a cross-modal mental representation of conspecific age classes. In Experiment 1, dogs were presented with images of an adult dog and a puppy projected side by side on a wall while a vocalization of either an adult dog or a puppy was played back simultaneously. To test the effect of relative body size between adult dog and puppy images, two size conditions (natural size and same size) were employed for visual stimuli. We examined dogs' looking behavior in response to cross-modally matched versus mismatched stimuli. We predicted that if dogs have cross-modal representations of age classes, they would exhibit prolonged attention toward matched images compared to mismatched ones. In Experiment 2, we administered the same paradigm within an eye-tracking experiment to further improve the measurement quality of dogs' looking times. However, dogs' looking times in either experiment did not demonstrate significant differences based on the match or mismatch between image and vocalization. Instead, we observed a size effect, indicating dogs' increased attention toward larger adult dog images compared to smaller puppy images. Consequently, we found no evidence of cross-modal representation of age class in dogs. Nonetheless, we found increased looking time and pupil size upon hearing puppy vocalizations compared to adult vocalizations in Experiment 2, suggesting that dogs exhibited heightened arousal when hearing puppy whining. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Dolphins are known to recognize their environment through echolocation. Previous studies have reported that they can discriminate the shape, size, thickness, and even material of objects through echolocation. However, little is known about the discrimination of quantities other than size and thickness (e.g., the number of objects). It is also unclear whether Weber's law (i.e., ratio dependency) holds for quantity discrimination through echolocation. In this study, we examined relative quantity judgments of visually occluded objects presented underwater by bottlenose dolphins. We found that they could discriminate pairs of same-sized objects ranging from one to eight, with performance improving as the difference ratio between the two numbers increased. In addition, their performance also improved as the magnitude of the number of objects involved increased. An additional test revealed that the accuracy of discrimination through echolocation was comparable to that of visual relative quantity judgments of the objects presented above water. On the other hand, under the condition that the overall size of each object (i.e., the sum of areas) was incongruent with the number of objects, performance was lower than when number and size were covarying. However, even within the incongruent condition, the effect of the number ratio was still observed, suggesting that the dolphins might have used various types of quantity information, such as number and size, flexibly to solve the task. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Associative learning models typically reflect statistical relationships between experienced events. Causal models can go beyond this information to specify the ways in which events are related. This meta-representational aspect of causal models allows them to reflect uncertainty about relationships between events: for example, if a light initially leads to sucrose but subsequently the light is experienced without sucrose, this might first support formation of a light-causes-sucrose model and subsequently lead to uncertainty over whether the model remained accurate. Prior studies of Pavlovian conditioning in rats manipulated sucrose-magazine access during extinction to produce uncertainty about reward presence or absence. Rats were sensitive to covering of the site of reward delivery, which was interpreted as evidence for a causal-model account reflecting uncertainty. However, associative accounts-based on the direct impact of the dipper mechanism used to deliver sucrose through secondary reinforcement or contextual renewal of responding-can also explain the results. In two new experiments, manipulation of the dipper mechanism through extinction and test phases resulted in behavior consistent with these associative accounts. However, demonstration of the importance of the sucrose dipper suggests that the reward delivery mechanism should be included in a causal model. Such a revised causal model also provides an account of the impact of manipulating the sucrose dipper. While these experiments do not conclusively decide between associative and causal models as explanations of rodent behavior, they do illustrate the value of incremental experimental study and the importance of methodological detail in addressing questions of comparative cognition. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Serial pattern learning describes behavior in which a subject anticipates not only the time and effort needed for the next reinforcer but also the pattern of time and effort to reinforcers after the first. Chandel et al. (2021) found that pigeons left a progressive (increasing ratio) schedule earlier than would have been optimal. They argued that the pigeons anticipated the harder-to-obtain reinforcers beyond the next one. In the present experiments, pigeons were trained on a progressive schedule for which each reinforcer was successively easier to obtain. However, the initial choice was between a fixed ratio schedule (FR23) for which a reinforcer was easier to obtain than the first reinforcer on the improving progressive schedule (32 pecks). Delayed discounting theory suggests that the pigeons would prefer the FR23 because more immediate reinforcers should be preferred, whereas serial pattern learning suggests that the progressive schedule might be preferred because easier-to-obtain reinforcers would follow the initially harder 32 pecks. In Experiment 1, a preference for the fixed ratio schedule was not found, however, in Experiment 2, when the two alternatives were equated for the number of reinforcers that could be obtained on each trial, a significant preference for the improving progressive schedule was found. The results of Experiment 2 were consistent with the serial pattern learning hypothesis. The pigeons did not choose the more immediate reinforcer associated with fixed ratio alternative. Rather, they showed a preference for the improving progressive schedule for which later reinforcers would be easier to obtain. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Detection dogs are required to learn and alert to multiple different odors during training and to generalize this learning to similar odors when working. They should be both sensitive to variation in the target odors and specific enough to avoid false alerts, but how readily they achieve this is likely to depend on the training method employed. The majority of agencies train by presenting single target odors in isolation, and adding additional odors consecutively, although recent research with rats suggests intermixing the target odors concurrently throughout training may be a more effective approach. This study therefore tested the relative efficacy of intermixed training in dogs. Using an odor-detection lineup, pet dogs were trained to detect two target odors, A and B. Those allocated to the "sequential" group were trained to criterion on odor A and then trained on odor B (or vice versa), the "compound" group were trained on a mixture of AB, and the "intermixed" group trained on A and B concurrently. Each dog was then tested on all combinations of the test stimuli (A, B, and AB), as well as combinations containing a novel interferent (AC, BC, and ABC). Results revealed that dogs trained by the intermixed method made significantly more correct (true positive) indications, and significantly fewer miss (false negative) indications than the other two methods, suggesting that intermixed training is more effective than currently used alternative training methods. Thus, for improved performance and generalization, we recommend detection dog training should use an intermixed method of training. (PsycInfo Database Record (c) 2025 APA, all rights reserved).

Utilizing Automated Cognitive Testing Systems (ACTS) with group-housed nonhuman primates offers a number of advantages over manual testing and computerized testing of singly housed subjects. To date, ACTS usage has been limited to great apes or African monkeys. Here, we detail what we have learned while implementing ACTS with socially housed squirrel monkeys and rhesus macaques and provide information about the training process. In addition, we examined the effects of age on learning acquisition. We found age differences in learning for both squirrel monkeys and rhesus monkeys. Older monkeys were not as proficient as younger monkeys on learning to use the touch screens (squirrel monkeys only), discrimination learning (rhesus monkeys only; note: squirrel monkeys were not trained to criterion on this task), and recognition learning (both species). Overall, ACTS provide a number of advantages for studying cognition in socially living nonhuman primates and can be used to further investigate cognitive decline whether related to natural aging processes or disease pathology. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Like many other species, dogs have a natural quantity judgment system to assist with decision making to maximize resources. Additionally, dogs are highly sensitive to, and influenced by, human-delivered ostensive (i.e., social) cues. Here, we assessed the influence of one such cue-a high, rising, positive "Oooh!" sound-on dogs' choice of differing quantities of pieces of food presented on two different plates. Subjects ( = 29) received 16 randomized trials of four conditions: 1 versus 1 paired with experimenter "Oooh!" while looking at the one plate, 1 versus 3, 3 versus 1 paired with experimenter "Oooh!," and 1 versus 1. As predicted, dogs chose the larger quantity more often in 1 versus 3 conditions. Contrary to one of our predictions, subjects chose the 1 versus 1+ "Oooh!" at chance levels. However, in support of another prediction, pairing the smaller reward with a positive intonation in 3 versus 1+ "Oooh!" significantly reduced dogs' choice of the larger reward. That is to say, without the presence of words, eye contact, or facial expressions, dogs followed a misguiding cue and chose a smaller reward that a stranger had deemed more valuable than a larger one. Local enhancement as well as a drive to increase social capital with the human are discussed as possible explanations. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Surface chemical cues from prey elicit elevated levels of tongue-flicking and striking behavior in many species of snakes and lizards. These responses are mediated by the vomeronasal system, and they may even occur in the absence of other sensory cues. How individuals of a species respond to prey chemical cues can reflect developmental, ecological, and evolutionary processes. Our focus in this study was ecologically based, and involved testing whether levels of chemosensory responding reflect the putative relative intake of prey types in nature. We tested 11 wild-caught adult gopher snakes () for their chemosensory responses, namely tongue flicking, in response to surface chemicals of natural prey items (rodent and bird) and to two control stimuli (distilled water and hexane). On average the snakes had significantly higher rates of tongue flicking toward prey cues than to control stimuli ( = .001). Responses to rodent and bird surface chemicals did not significantly differ from each other ( = .35). Tongue-flick responses to rodent surface chemicals were significantly higher than to both water and hexane (s < .01), while responses to bird surface chemicals were significantly higher than to water ( < .05) but not to hexane ( = .12). (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Contrafreeloading is defined as choosing to perform work to obtain a reward, despite the presence of an identical, freely available alternative. According to standard learning and optimal foraging theories, it should not exist. Thus, any evidence of such behavior is noteworthy. We briefly review the recently introduced play hypothesis, which proposes that contrafreeloading is more likely if the action involved is viewed as play rather than work (i.e., agreeable rather than aversive). One might consequently expect species that are relatively more playful to be more likely to engage in contrafreeloading. We evaluated this possibility by testing purportedly playful umbrella cockatoos ); we studied four residents of a bird sanctuary in upstate New York (Dudley, JJ, Poly, and Teddy Bear). The task involved choosing between shelled and deshelled almonds; the former choice constituting evidence of contrafreeloading. We documented contrafreeloading in a novel species and then compared our results with previously published data on the reportedly less playful Grey parrots (). Individually, a higher percentage of cockatoos engaged in contrafreeloading on more than half the trials than did the Greys, with statistically similar levels of individual variation, but the overall amount of contrafreeloading was not statistically significantly different between the species at a group level. We discuss possible reasons for these findings. Additionally, we examine similarities in the behavioral expression of play and contrafreeloading. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Maze studies have provided substantial information about nonhuman cognition, such as insights on navigational strategies, spatial memory, and choice discriminations. This knowledge can aid in how we understand the foraging strategies of many animals, particularly understudied and endangered species, such as the Guatemalan beaded lizard (). These actively foraging lizards rely on chemoreception to locate prey, but it is unknown to what extent they engage in olfaction and vomerolfaction to hunt and navigate their environment. We investigated how Guatemalan beaded lizards moved through a physical maze. When navigating an eight-arm radial maze with all arms baited, lizards tended to turn into the immediately adjacent arm in a single direction, similar to other reptiles that have been tested in radial arm mazes. In a T-maze, the lizards had to discriminate between arms that contained scent and no-scent from a distance. They were generally unable to choose the baited (correct) arm at levels greater than chance, indicating an inability for this discrimination. With the addition of a scent trail, however, all lizards chose the baited arm at levels significantly above chance, and this increased accuracy was correlated with increased latency to make the arm choice. The lizards also demonstrated a decreased rate of tongue flicking as proximity to reward increased. Guatemalan beaded lizards can efficiently navigate a radial arm maze and can successfully use vomerolfaction with substrate-borne cues to locate prey, but they appear to have minimal olfaction abilities when sensing from a distance. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Play behavior has been extensively studied across species, but its direct role in social relationships remains unclear. Here we use an "isolation versus separation" protocol to identify behaviors associated with relationship renewal in adolescent female rats. Members of a dyad that had been separated for 24 hr, without isolation from other peers, initially increased investigative behaviors relative to nonseparated peers; however, in contrast with social isolation, separation by itself did not increase rough-and-tumble play. The data suggest that increased play following isolation depends on general motivations, rather than a "peer-specific" drive to renew relationships with an individual. This is consistent with a role of play in more general social learning rather than reestablishing bonds or expectations. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Many parrot species exhibit a high degree of limb lateralization on both the individual and species levels. In particular, the members of the cockatoo family are left-footed for food-holding at proportions reminiscent of right-handedness in humans. Here, we examine the limb lateralization of the Goffin's cockatoo (), a tool-using and technically proficient species used as a model of parrot cognition. First, we investigated the postural origins theory, originally proposed in primates to explain handedness. According to this theory, the hand that was used by ancestral primates to cling to trees developed finer motor control. Using a series of problem-solving tasks, we tested the possibility that the parrot's postural foot, which is similarly used to grasp tree branches, could be more motorically skilled. Although we did not find support for this idea, we did discover that task type does affect foot use, as subjects switched from using their food-holding dominant foot to their other foot during reaching tasks. We also found that the cockatoos more flexibly switched and used both feet when faced with more challenging tasks. Secondly, we attempted a partial replication of a previous study with parrots derived from the enhanced cognition hypothesis, which claimed that more lateralized individuals were better problem solvers. However, we did not find this relationship to be significant in any of our tasks. We did confirm that individual Goffin's cockatoos are extremely limb lateralized for food-holding in addition to other tasks, which may play a role in their approaches to problem-solving. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Typical approaches to study self-control present subjects with a simultaneous choice between a larger-later (LL) reinforcer and a smaller-sooner (SS) reinforcer. In contrast, in patch-leaving tasks, subjects choose between staying at a patch for an SS (or LL) reinforcer and leaving for an LL (or SS) reinforcer. Previous studies show that blue jays, monkeys, humans, and rats prefer the SS reinforcer in binary-choice tasks, whereas the same subjects prefer the LL reinforcer in equivalent patch-leaving tasks. The current study systematically replicated this research using pigeons. Six pigeons responded in a binary-choice task and in two patch-leaving tasks in which staying led to an LL (Patch-L) or SS (Patch-S) reinforcer. Across conditions, the SS reinforcer delay varied from 5 to 55 s; the LL reinforcer delay was always 60 s. In binary-choice conditions, subjects preferred the SS reinforcer. In Patch-L and Patch-S conditions, subjects preferred the LL and SS reinforcer, respectively, reflecting a bias to stay at the patch. This bias persisted when the stay response was more effortful and when the delays to both reinforcers were equal. This may reflect a species-specific win-stay bias and the differential consequences of staying (which led to a stimulus signaling food) versus leaving (which led to a stimulus never associated with food). Thus, we propose a conditioned-reinforcement account of intertemporal choice in patch-leaving contexts. We suggest several avenues for further investigations of the mechanisms underlying intertemporal choice in different contexts and question the economic equivalence of the operant and patch-leaving procedures. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

The ephemeral reward task involves providing subjects with a choice between two distinctive stimuli, A and B, each containing an identical reward. If A is chosen, the reward associated with A is obtained and the trial is over. If B is chosen, the reward associated with B is obtained but A remains, and the reward associated with A can be obtained as well. Thus, the reward-maximizing solution is to choose B first. Although cleaner fish (wrasse) and parrots easily acquire the optimal response by choosing B, paradoxically, several nonhuman primate species, as well as rats and pigeons, do not. It appears that some species do not associate their choice and reward with the second reward. Surprisingly, research in an operant context with pigeons and rats suggests that inserting a delay between the choice and reward facilitates optimal choice. It is suggested that impulsivity may be, in part, responsible for the difficulty of the task. In an attempt to better understand this task, we trained human subjects on an operant version of this task, with and without a brief delay between choice and reward and found that many subjects failed to learn to choose optimally, independent of the delay. Furthermore, performance on this task was not correlated with a task thought to measure impulsivity, the Balloon Analog Risk Task or with the Abbreviated Impulsivity Survey. We concluded that, for humans, the task is confusing because there is no incorrect response, only good and better, and better is not easily discriminated. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

This article discusses the ephemeral reward task and how it is not always a clear and concise choice. This is demonstrated through some animal studies involving birds and primates. This article also shows that when compared to human studies, that there are positive correlations between the BART and optimal choice in the ephemeral reward task, meaning that those who took more risks also were more inclined to be optimal. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Comments on an article by Jay W. Schwartz , Kayleigh H. Pierson, and Alexander K. Reece (see record 2024-19488-001). In this issue, Schwartz et al. (2024) tackle the pitch rule in humans by testing to what extent we use pitch alone to judge emotional arousal across closely and distantly related animal species. The findings of Schwartz et al. open a number of intriguing possibilities for future research: Notably important additional steps would include to further investigate the accuracy of the pitch rule across closely and distantly related species. Upon this, in order to study the evolutionary ancestry of the pitch rule, it will be necessary to study its applicability across nonhumans. Particularly interesting would be the inclusion of subject species that have been found to eavesdrop on heterospecific alarm calls. Previous research (see Hoeschele, 2017 for a review) as well as present findings on human ratings of macaque versus cricket calls also suggest that we should additionally focus on sound features that compliment emotional arousal rating beyond pitch such as spectral information. (PsycInfo Database Record (c) 2024 APA, all rights reserved).