Constrained Choice: Children's and Adults' Attribution of Choice to a Humanoid Robot.

Young children, like adults, understand that human agents can flexibly choose different actions in different contexts, and they evaluate these agents based on such choices. However, little is known about children's tendencies to attribute the capacity to choose to robots, despite increased contact with robotic agents. In this paper, we compare 5- to 7-year-old children's and adults' attributions of free choice to a robot and to a human child by using a series of tasks measuring agency attribution, action prediction, and choice attribution. In morally neutral scenarios, children ascribed similar levels of free choice to the robot and the human, while adults were more likely to ascribe free choice to the human. For morally relevant scenarios, however, both age groups considered the robot's actions to be more constrained than the human's actions. These findings demonstrate that children and adults hold a nuanced understanding of free choice that is sensitive to both the agent type and constraints within a given scenario.

Individual differences in gesture interpretation predict children's propensity to pick a gesturer as a good informant.

To learn from others, children rely on cues (e.g., familiarity, confidence) to infer who around them will provide useful information. We extended this research to ask whether children will use an informant's inclination to gesture as a marker of whether or not the informant is a good person to learn from. Children (N = 459, ages 4-12 years) watched short videos in which actresses made statements accompanied by meaningful iconic gestures, beat gestures (which act as prosodic markers with speech), or no gestures. After each trial, children were asked "Who do you think would be a good teacher?" (good teacher [experimental] condition) or "Who do you think would be a good friend?" (good friend [control] condition). Results show that children do believe that someone who produces iconic gesture would make a good teacher compared with someone who does not, but this is only later in childhood and only if children have the propensity to see gesture as meaningful. The same effects were not found in the good friend condition, indicating that children's responses are not just about liking an adult who gestures more. These findings have implications for how children attend to and learn from instructional gesture.

The application of noninvasive, restraint-free eye-tracking methods for use with nonhuman primates.

Over the past 50 years there has been a strong interest in applying eye-tracking techniques to study a myriad of questions related to human and nonhuman primate psychological processes. Eye movements and fixations can provide qualitative and quantitative insights into cognitive processes of nonverbal populations such as nonhuman primates, clarifying the evolutionary, physiological, and representational underpinnings of human cognition. While early attempts at nonhuman primate eye tracking were relatively crude, later, more sophisticated and sensitive techniques required invasive protocols and the use of restraint. In the past decade, technology has advanced to a point where noninvasive eye-tracking techniques, developed for use with human participants, can be applied for use with nonhuman primates in a restraint-free manner. Here we review the corpus of recent studies (N=32) that take such an approach. Despite the growing interest in eye-tracking research, there is still little consensus on "best practices," both in terms of deploying test protocols or reporting methods and results. Therefore, we look to advances made in the field of developmental psychology, as well as our own collective experiences using eye trackers with nonhuman primates, to highlight key elements that researchers should consider when designing noninvasive restraint-free eye-tracking research protocols for use with nonhuman primates. Beyond promoting best practices for research protocols, we also outline an ideal approach for reporting such research and highlight future directions for the field.

Problem solving flexibility across early development.

Cognitive flexibility allows individuals to adapt to novel situations. However, this ability appears to develop slowly over the first few years of life, mediated by task complexity and opacity. We used a physically simple novel task, previously tested with nonhuman primates, to explore the development of flexible problem solving in 2-, 3-, and 4-year-old children from a developmental and comparative perspective. The task goal was to remove barriers (straws) from a clear tube to release a ball. The location of the ball, and therefore the number of straws necessary to retrieve it, varied across two test phases (four of five straws and two of five straws, respectively). In Test Phase 1, all children retrieved the ball in Trial 1 and 83.61% used the most efficient method (removing only straws below the ball). Across Phase 1 trials, 4-year-olds were significantly more efficient than 2-year-olds, and solve latency decreased for all age groups. Test Phase 2 altered the location of the ball, allowing us to explore whether children could flexibly adopt a more efficient solution when their original (now inefficient) solution remained available. In Phase 2, significantly more 4-year-olds than 2-year-olds were efficient; the older children showed greater competency with the task and were more flexible to changing task demands than the younger children. Interestingly, no age group was as flexible in Phase 2 as previously tested nonhuman primates, potentially related to their relatively reduced task exploration in Phase 1. Therefore, this causally clear task revealed changes in cognitive flexibility across both early childhood and species.

Learning From Others: The Effects of Agency on Event Memory in Young Children.

Little is known about the influence of social context on children's event memory. Across four studies, we examined whether learning that could occur in the absence of a person was more robust when a person was present. Three-year-old children (N = 125) viewed sequential events that either included or excluded an acting agent. In Experiment 1, children who viewed an agent recalled more than children who did not. Experiments 2a and 2b utilized an eye tracker to demonstrate this effect was not due to differences in attention. Experiment 3 used a combined behavioral and event-related potential paradigm to show that condition effects were present in memory-related components. These converging results indicate a particular role for social knowledge in supporting memory for events.

A competitive drive? Same-sex attentional preferences in capuchins.

In primates, faces provide information about several characteristics of social significance, including age, physical health, and biological sex. However, despite a growing literature on face processing and visual attention in a number of primate species, preferences for same- or opposite-sex faces have not yet been examined. In the current study, we explore the role of conspecific sex on visual attention in two groups of capuchin monkeys. Subjects were shown a series of image pairs on a Tobii Pro TX300 eye tracker, each depicting an unfamiliar male and an unfamiliar female face. Given the behavioral evidence of mate choice in both sexes, we hypothesized that capuchins would preferentially attend to images of unfamiliar conspecifics of the opposite sex. Our alternative hypothesis was that capuchins would preferentially attend to same-sex individuals to assess potential competitors. Our results provide support for our alternative hypothesis. When comparing attention to each stimuli type across sexes, females spent significantly larger percentages of time than males looking at female photos, whereas males spent significantly larger percentages of time than females looking at male photos. Within each sex, females looked for significantly larger percentages of time to female versus male images. Males also looked for larger percentages of time to same-sex images, though not significantly. To our knowledge, these data are the first to demonstrate significant sex-biased attentional preferences in adult primates of any species, and suggest that, for capuchins, potential competitors garner more attention than potential mates. In addition, our findings have implications for studies of visual attention and face processing across the primate order, and suggest that researchers need to control for these demographic factors in their experimental designs.

Through their eyes: The influence of social models on attention and memory in capuchin monkeys (Sapajus apella).

The ability to learn socially is of critical importance across a wide variety of species, as it allows knowledge to be passed quickly among individuals without the need of time-consuming trial-and-error learning. Among primates, social learning research has been particularly focused on foraging tasks, including transmission dynamics and the demonstration characteristics that appear to support social learning. Less work has focused on the attentional salience of the information being viewed, especially in New World monkeys. We used a noninvasive eye-tracking paradigm previously used in human infants and great apes to examine the salience of social modeling for memory in capuchin monkeys. Like human infants and apes, capuchins were significantly more likely to remember an event that included a social model as opposed to a nonsocial model. This article provides some of the first evidence that capuchin memory is altered by the presence of a social model and presents a novel method for assessing cognitive capabilities in this species. Whether this "social memory bias" is shared across the primate order, or is present only in taxa that regularly rely on social information, is an important avenue for future research. (PsycINFO Database Record

Children's expectations about conventional and moral behaviors of ingroup and outgroup members.

Although children demonstrate robust social preferences for ingroup members early in ontogeny, it is not yet clear whether these preferences are based on children generally liking people who are more familiar or on children holding specific biased beliefs about people in their ingroup as compared with people in their outgroup. Here, we investigated the origins of humans' propensity to link ingroup members with positive behaviors and outgroup members with negative behaviors by asking whether linguistic group membership influences children's expectations of how people will act. Our findings indicate that the effect of group membership on children's expectations about other people's actions varies across both domain (moral and conventional) and age. Whereas all children in our study (3- to 11-year-olds) expected ingroup members to be more likely to conform to social conventions and expected outgroup members to be more likely to break conventional rules, only older children (7- to 11-year-olds) used social group membership to form expectations about which people would be more likely to act morally versus immorally. Thus, younger children do not automatically form biased character judgments based on group membership, although they do understand that social group membership is particularly relevant for reasoning about which people will be more likely to act in line with social norms.

Social Models Enhance Apes' Memory for Novel Events.

Nonhuman primates are more likely to learn from the actions of a social model than a non-social "ghost display", however the mechanism underlying this effect is still unknown. One possibility is that live models are more engaging, drawing increased attention to social stimuli. However, recent research with humans has suggested that live models fundamentally alter memory, not low-level attention. In the current study, we developed a novel eye-tracking paradigm to disentangle the influence of social context on attention and memory in apes. Tested in two conditions, zoo-housed apes (2 gorillas, 5 chimpanzees) were familiarized to videos of a human hand (social condition) and mechanical claw (non-social condition) constructing a three-block tower. During the memory test, subjects viewed side-by-side pictures of the previously-constructed block tower and a novel block tower. In accordance with looking-time paradigms, increased looking time to the novel block tower was used to measure event memory. Apes evidenced memory for the event featuring a social model, though not for the non-social condition. This effect was not dependent on attention differences to the videos. These findings provide the first evidence that, like humans, social stimuli increase nonhuman primates' event memory, which may aid in information transmission via social learning.

Infants' and young children's imitation of linguistic in-group and out-group informants.

Although children can use social categories to intelligently select informants, children's preference for in-group informants has not been consistently demonstrated across age and context. This research clarifies the extent to which children use social categories to guide learning by presenting participants with a live or video-recorded action demonstration by a linguistic in-group and/or out-group model. Participants' (N = 104) propensity to imitate these actions was assessed. Nineteen-month-olds did not selectively imitate the actions of the in-group model in live contexts, though in-group preferences were found after watching the demonstration on video. Three-year-olds selectively imitated the actions demonstrated by the in-group member regardless of context. These results indicate that in-group preferences have a more nuanced effect on social learning than previous research has indicated.

Neighborhood linguistic diversity predicts infants' social learning.

Infants' direct interactions with caregivers have been shown to powerfully influence social and cognitive development. In contrast, little is known about the cognitive influence of social contexts beyond the infant's immediate interactions with others, for example, the communities in which infants live. The current study addressed this issue by asking whether neighborhood linguistic diversity predicts infants' propensity to learn from diverse social partners. Data were taken from a series of experiments in which 19-month-old infants from monolingual, English-speaking homes were tested in paradigms that assessed their tendency to imitate the actions of an adult who spoke either English or Spanish. Infants who lived in more linguistically diverse neighborhoods imitated more of the Spanish speaker's actions. This relation was observed in two separate datasets and found to be independent from variation in infants' general imitative abilities, age, median family income and population density. These results provide novel evidence suggesting that infants' social learning is predicted by the diversity of the communities in which they live.