Chimpanzees (Pan troglodytes) recognize spatial and object correspondences between a scale model and its referent

In the present study, the contributions of spatial and object features to chimpanzees' comprehension of scale models were examined. Seven chimpanzees that previously demonstrated the ability to use a scale model as an information source for the location of a hidden item were tested under conditions manipulating the feature correspondence and spatial-relational correspondence between objects in the model and an outdoor enclosure. In Experiment 1, subjects solved the task under two conditions in which one object cue (color or shape) was unavailable, but positional cues remained. Additionally, performance was above chance under a third condition in which both types of object cues, but not position cues, were available. In Experiment 2, 2 subjects solved the task under a condition in which shape and color object cues were simultaneously unavailable. The results suggest that, much like young children, chimpanzees are sensitive to both object and spatial-relational correspondences between a model and its referent.     

Attribution of dispositional states by 12-month-olds

The ability to interpret the behavior of other individuals is essential for effective social functioning. Many investigators now believe that even young infants can recognize that agents act toward goals. Here we report three experiments suggesting that 12-month-old infants not only can recognize goal-related action, but also can interpret future actions of an actor on the basis of previously witnessed behavior in another context. The possibility that this inference is made through the attribution of mental states is discussed.     

Sleep,resilience, and psychological distress in United States military Veterans

Sleep problems are prevalent among Veterans. Left untreated, such problems may elevate psychological distress and increase risk of subsequent mental health disorders. Psychological resilience may buffer against negative psychological outcomes, yet the relationship between sleep and resilience has not been studied. This study explored poor sleep, resilience, and psychological distress using questionnaires collected as part of the Study of Post-Deployment Mental Health. Participants (N = 1,118) had served in the US military since September 11, 2001, had one or more overseas deployments, and were free from a past-month DSM-defined mental health disorder. Hierarchical linear regression was used to examine the association between poor sleep quality (Pittsburgh Sleep Quality Index total score) and psychological distress (Global Symptom Index; Symptom Checklist-90-R), controlling for demographic and health characteristics. Moderation analyses tested for a potential buffering effect of resilience (Connor-Davidson Resilience Scale). Poor sleeping Veterans had worse physical and psychological health, lower resilience, and endorsed more lifetime traumatic events. Poor sleep was associated with greater psychological distress controlling for health and demographic characteristics. Both resilience factors—adaptability and self-efficacy—had significant buffering effects on the relationship between poor sleep and psychological distress, suggesting that resilience may protect against negative outcomes in poor sleepers. Additional research is warranted to better understand the relationships between sleep, resilience, and psychological distress. Such research may inform pertinent prevention efforts, including interventions that improve sleep, enhance resilience, and protect against incident mental health diagnoses.     

Conceptual constraints and mechanisms in children's selective learning

Although we can support Heyes’ call for more research on mechanisms, we disagree that the problem has been ignored as Heyes suggests. We also doubt that basic learning mechanisms are alone sufficient to account for the broad range of findings in the selective social learning literature. Although phylogenetically shared learning mechanisms must support selective social learning, we believe that they must also be guided by top‐down conceptual considerations that may be special to humans. Research to date has been focused on establishing the boundary conditions on selective social learning, with the goal of making generalizations that will constrain theorizing about the character of that special knowledge. This is critical to our understanding of both why and how selective social learning manifests in children.     

Do 5-month-old infants see humans as material objects?

Infants expect objects to be solid and cohesive, and to move on continuous paths through space. In this study, we examine whether infants understand that human beings are material objects, subject to these same principles. We report that 5-month-old infants apply the constraint of continuous motion to inanimate blocks, but not to people. This suggests that young infants have two separate modes of construal: one for inanimate objects and another for humans.     

Continuity in social cognition from infancy to childhood

Research examining the development of social cognition has largely been divided into two areas: infant perception of intentional agents, and preschoolers’ understanding of others’ mental states and beliefs (theory of mind). Many researchers have suggested that there is continuity in social cognitive development such that the abilities observed in infancy are related to later preschool ability, yet little empirical evidence exists for this claim. Here, we present preliminary evidence that capacities specific to the social domain contribute to performance in social cognition tasks both during infancy and in early childhood. Specifically, looking time patterns in an infant social cognition task correlated with preschool theory of mind; however, no such relationship was found for infants in a nonsocial cognition task.     

Scale-model comprehension by chimpanzees (Pan troglodytes)

The ability of chimpanzees (Pan troglodytes) to recognize the correspondence between a scale model and its real-world referent was examined. In Experiments 1 and 2, an adult female and a young adult male watched as an experimenter hid a miniature model food in 1 of 4 sites in a scale model. Then, the chimpanzees were given the opportunity to find the real food item that had been hidden in the analogous location in the real room. The female performed significantly above chance, whereas the male performed at chance level. Experiments 3 and 4 tested 5 adult and 2 adolescent chimpanzees in a similar paradigm, using a scale model of the chimpanzees' outdoor area. Results indicate that some adult chimpanzees were able to reliably demonstrate an understanding of the relationship between a scale model and the larger space it represented, whereas other subjects were constrained by inefficient and unsuccessful search patterns.     

Young children show a dissociation in looking and pointing behavior in falling events

Studies of social cognitive reasoning have demonstrated instances of children engaging in eye gaze patterns toward correct answers even when pointing or verbal responses are directed toward incorrect answers. Findings such as these have spawned seminal theories, yet no consensus has been reached regarding the characteristics of the knowledge guiding these responses. We tested 2-year-olds’ eye gaze and pointing behavior in an occluded falling event to examine these behaviors within the domain of physical reasoning. In the simplest variant of the task, all children showed correct gaze to the final location of a ball dropped down a curved tube, but only a subset of these children pointed to the correct location. (Others pointed reliably to a location directly below the release point.) With two tubes, all children directed the majority of looking and pointing responses to this erroneous location. The findings are considered in relation to existing models of representational change.     

The effect of response contingencies on scale model task performance by chimpanzees (Pan troglodytes)

The effects of modified procedures on chimpanzees' (Pan troglodytes) performance in a scale model comprehension task were examined. Seven chimpanzees that previously participated in a task in which they searched an enclosure for a hidden item after watching an experimenter hide a miniature item in the analogous location in a scale model were retested under procedures incorporating response costs. In Experiment 1, chimpanzees were trained under procedures that rewarded only item retrievals occurring on the 1st search attempt. During test trials, 6 chimpanzees performed above chance, including 4 that were previously unsuccessful under the original procedures (V. A. Kuhlmeier, S. T. Boysen, & K. L. Mukobi, 1999). Experiment 2 compared performance under the new and original procedures. Results indicated that for some chimpanzees, performance depended on procedures that decreased the use of competing search strategies and encouraged strategies based on information from the scale model.