Katherine Nagell

Bio: Katherine Nagell is an academic researcher from Emory University. The author has contributed to research in topics: Gesture & Joint attention. The author has an hindex of 5, co-authored 5 publications receiving 3094 citations.

Social Cognition, joint attention and communicative Competence from 9 to 15 months of age

Abstract: At around 1 year of age, human infants display a number of new behaviors that seem to indicate a newly emerging understanding of other persons as intentional beings whose attention to outside objects may be shared, followed into, and directed in various ways. These behaviors have mostly been studied separately. In the current study, we investigated the most important of these behaviors together as they emerged in a single group of 24 infants between 9 and 15 months of age. At each of seven monthly visits, we measured joint attentional engagement, gaze and point following, imitation of two different kinds of actions on objects, imperative and declarative gestures, and comprehension and production of language. We also measured several nonsocial-cognitive skills as a point of comparison. We report two studies. The focus of the first study was the initial emergence of infants' social-cognitive skills and how these skills are related to one another developmentally. We found a reliable pattern of emergence: Infants progressed from sharing to following to directing others' attention and behavior. The nonsocial skills did not emerge predictably in this developmental sequence. Furthermore, correlational analyses showed that the ages of emergence of all pairs of the social-cognitive skills or their components were inter-related. The focus of the second study was the social interaction of infants and their mothers, especially with regard to their skills of joint attentional engagement (including mothers' use of language to follow into or direct infants' attention) and how these skills related to infants' early communicative competence. Our measures of communicative competence included not only language production, as in previous studies, but also language comprehension and gesture production. It was found that two measures--the amount of time infants spent in joint engagement with their mothers and the degree to which mothers used language that followed into their infant's focus of attention--predicted infants' earliest skills of gestural and linguistic communication. Results of the two studies are discussed in terms of their implications for theories of social-cognitive development, for theories of language development, and for theories of the process by means of which human children become fully participating members of the cultural activities and processes into which they are born.

Processes of social learning in the tool use of chimpanzees (Pan troglodytes) and human children (Homo sapiens).

Abstract: Common chimpanzees (Pan troglodytes) and 2-year-old human children (Homo sapiens) were presented with a rakelike tool and a desirable but out-of-reach object. One group of subjects observed a human demonstrator use the tool in one way, and another group observed a demonstrator use the tool in another way. Children in both cases did what the model did. Chimpanzee subjects, however, behaved identically in the 2 model conditions. Both groups performed better than subjects who saw no demonstration. This pattern of results suggest that the chimpanzees were paying attention to the general functional relations in the task and to the results obtained by the demonstrator but not to the actual methods of tool use demonstrated. Human children were focused on the demonstrator's actual methods of tool use (her behavior). The different social learning processes used by the 2 species have implications for their different forms of social organization.

The learning and use of gestural signals by young chimpanzees: A trans-generational study

Abstract: Observations of chimpanzee gestural communication are reported. The observations represent the third longitudinal time point of an ongoing study of the Yerkes Primate Center Field Station chimpanzee group. In contrast to observations at the first two time points, the current observations are of a new generation of infants and juveniles. There were two questions. The first concerned how young chimpanzees used their gestures, with special focus on the flexibility or intentionality displayed. It was found that youngsters quite often used the same gesture in different contexts, and different gestures in the same context. In addition, they sometimes used gestures in combinations in a single social encounter, these combinations did not convey intentions that could not be conveyed by the component gestures, however. It was also found that individuals adjusted their choice of signals depending on the attentional state of the recipient. The second question was how chimpanzees acquired their gestural signals. In general, it was found that there was little consistency in the use of gestures among individuals, especially for non-play gestures, with much individual variability both within and across generations. There were also a number of idiosyncratic gestures used by single individuals at each time point. It was concluded from these results that youngsters were not imitatively learning their communicatory gestures from conspecifics, but rather that they were individually conventionalizing them with each other. Implications of these findings for the understanding of chimpanzee communication and social learning are discussed.

The Ontogeny of Chimpanzee Gestural Signals: A Comparison Across Groups and Generations

Abstract: Observations of the gestural communication of two groups of captive chimpanzees are reported. For one group the observations represent a fourth longitudinal time point over a 12 year period; the other group was observed for the first time. There were two main questions. The first concerned how young chimpanzees use their gestures, with special foci on the flexibility displayed in signal use and on the sensitivity to audience displayed in signal choice. It was found that chimpanzees are very flexible in their signal use (different signals for same goal, same signal for different goals) and somewhat sensitive to audience (signal choice based on attentional state of recipient). The second question was how chimpanzees acquire their gestural signals. Comparisons between the two groups showed much individual variability both within and between groups. In addition, when each of the two contemporary groups was compared with the previous longitudinal time points for one of the groups, no differences in concordance were found. It was concluded that youngsters were not imitatively learning their communicatory gestures from conspecifics, but rather that they were individually ritualizing them with one another in social interaction. An experimental study in which two individuals were taught new gestures and returned to their groups — with no subsequent signs of imitation — corroborated this conclusion. Implications of the current findings for the understanding of chimpanzee communication and social learning are discussed.

Understanding and sharing intentions: The origins of cultural cognition

Abstract: We propose that the crucial difference between human cognition and that of other species is the ability to participate with others in collaborative activities with shared goals and intentions: shared intentionality. Participation in such activities requires not only especially powerful forms of intention reading and cultural learning, but also a unique motivation to share psychological states with oth- ers and unique forms of cognitive representation for doing so. The result of participating in these activities is species-unique forms of cultural cognition and evolution, enabling everything from the creation and use of linguistic symbols to the construction of social norms and individual beliefs to the establishment of social institutions. In support of this proposal we argue and present evidence that great apes (and some children with autism) understand the basics of intentional action, but they still do not participate in activities involving joint intentions and attention (shared intentionality). Human children's skills of shared intentionality develop gradually during the first 14 months of life as two ontogenetic pathways intertwine: (1) the general ape line of understanding others as animate, goal-directed, and intentional agents; and (2) a species-unique motivation to share emotions, experience, and activities with other persons. The develop- mental outcome is children's ability to construct dialogic cognitive representations, which enable them to participate in earnest in the collectivity that is human cognition.

Empathy: Its ultimate and proximate bases.

Abstract: There is disagreement in the literature about the exact nature of the phenomenon of empathy. There are emotional, cogni- tive, and conditioning views, applying in varying degrees across species. An adequate description of the ultimate and proximate mecha- nism can integrate these views. Proximately, the perception of an object's state activates the subject's corresponding representations, which in turn activate somatic and autonomic responses. This mechanism supports basic behaviors (e.g., alarm, social facilitation, vicar- iousness of emotions, mother-infant responsiveness, and the modeling of competitors and predators) that are crucial for the reproduc- tive success of animals living in groups. The Perception-Action Model (PAM), together with an understanding of how representations change with experience, can explain the major empirical effects in the literature (similarity, familiarity, past experience, explicit teach- ing, and salience). It can also predict a variety of empathy disorders. The interaction between the PAM and prefrontal functioning can also explain different levels of empathy across species and age groups. This view can advance our evolutionary understanding of empa- thy beyond inclusive fitness and reciprocal altruism and can explain different levels of empathy across individuals, species, stages of de- velopment, and situations.

Origins of Human Communication

Abstract: Winner, 2009 Eleanor Maccoby Book Award in Developmental Psychology, presented by the American Psychological Association. and Honorable Mention, Literature, Language & Linguistics category, 2008 PROSE Awards presented by the Professional/Scholarly Publishing Division of the Association of American Publishers. Human communication is grounded in fundamentally cooperative, even shared, intentions. In this original and provocative account of the evolutionary origins of human communication, Michael Tomasello connects the fundamentally cooperative structure of human communication (initially discovered by Paul Grice) to the especially cooperative structure of human (as opposed to other primate) social interaction. Tomasello argues that human cooperative communication rests on a psychological infrastructure of shared intentionality (joint attention, common ground), evolved originally for collaboration and culture more generally. The basic motives of the infrastructure are helping and sharing: humans communicate to request help, inform others of things helpfully, and share attitudes as a way of bonding within the cultural group. These cooperative motives each created different functional pressures for conventionalizing grammatical constructions. Requesting help in the immediate you-and-me and here-and-now, for example, required very little grammar, but informing and sharing required increasingly complex grammatical devices. Drawing on empirical research into gestural and vocal communication by great apes and human infants (much of it conducted by his own research team), Tomasello argues further that humans' cooperative communication emerged first in the natural gestures of pointing and pantomiming. Conventional communication, first gestural and then vocal, evolved only after humans already possessed these natural gestures and their shared intentionality infrastructure along with skills of cultural learning for creating and passing along jointly understood communicative conventions. Challenging the Chomskian view that linguistic knowledge is innate, Tomasello proposes instead that the most fundamental aspects of uniquely human communication are biological adaptations for cooperative social interaction in general and that the purely linguistic dimensions of human communication are cultural conventions and constructions created by and passed along within particular cultural groups. Jean Nicod Lectures A Bradford Book

Development and neurophysiology of mentalizing.

Abstract: The mentalizing (theory of mind) system of the brain is probably in operation from ca. 18 months of age, allowing implicit attribution of intentions and other mental states. Between the ages of 4 and 6 years explicit mentalizing becomes possible, and from this age children are able to explain the misleading reasons that have given rise to a false belief. Neuroimaging studies of mentalizing have so far only been carried out in adults. They reveal a system with three components consistently activated during both implicit and explicit mentalizing tasks: medial prefrontal cortex (MPFC), temporal poles and posterior superior temporal sulcus (STS). The functions of these components can be elucidated, to some extent, from their role in other tasks used in neuroimaging studies. Thus, the MPFC region is probably the basis of the decoupling mechanism that distinguishes mental state representations from physical state representations; the STS region is probably the basis of the detection of agency, and the temporal poles might be involved in access to social knowledge in the form of scripts. The activation of these components in concert appears to be critical to mentalizing.