Jessica A. Sommerville

Shared representations between self and other: a social cognitive neuroscience view

The abilities to identify with others and to distinguish between self and other play a pivotal role in intersubjective transactions. Here, we marshall evidence from developmental science, social psychology and neuroscience (including clinical neuropsychology) that support the view of a common representation network (both at the computational and neural levels) between self and other. However, sharedness does not mean identicality, otherwise representations of self and others would completely overlap, and lead to confusion. We argue that self-awareness and agency are integral components for navigating within these shared representations. We suggest that within this shared neural network the inferior parietal cortex and the prefrontal cortex in the right hemisphere play a special role in interpersonal awareness.

Weaving the fabric of social interaction: Articulating developmental psychology and cognitive neuroscience in the domain of motor cognition

In this article, we bring together recent findings from developmental science and cognitive neuroscience to argue that perception-action coupling constitutes the fundamental mechanism of motor cognition. A variety of empirical evidence suggests that observed and executed actions are coded in a common cognitive and neural framework, enabling individuals to construct shared representations of self and other actions. We review work to suggest that such shared representations support action anticipation, organization, and imitation. These processes, along with additional computational mechanisms for determining a sense of agency and behavioral regulation, form the fabric of social interaction. In addition, humans possess the capacity to move beyond these basic aspects of action analysis to interpret behavior at a deeper level, an ability that may be outside the scope of the mirror system. Understanding the nature of shared representations from the vantage point of developmental and cognitive science and neuroscience has the potential to inform a range of motor and social processes. This perspective also elucidates intriguing new directions and research questions and generates specific hypotheses regarding the impact of early disorders (e.g., developmental movement disorders) on subsequent action processing.

Cognitive control factors in speech perception at 11 months

The development of speech perception during the 1st year reflects increasing attunement to native language features, but the mechanisms underlying this development are not completely understood. One previous study linked reductions in nonnative speech discrimination to performance on nonlinguistic tasks, whereas other studies have shown associations between speech perception and vocabulary growth. The present study examined relationships among these abilities in 11-month-old infants using a conditioned head-turn test of native and nonnative speech sound discrimination, nonlinguistic object-retrieval tasks requiring attention and inhibitory control, and the MacArthur-Bates Communicative Development Inventory (L. Fenson et al., 1993). Native speech discrimination was positively linked to receptive vocabulary size but not to the cognitive control tasks, whereas nonnative speech discrimination was negatively linked to cognitive control scores but not to vocabulary size. Speech discrimination, vocabulary size, and cognitive control scores were not associated with more general cognitive measures. These results suggest specific relationships between domain-general inhibitory control processes and the ability to ignore variation in speech that is irrelevant to the native language and between the development of native language speech perception and vocabulary.

Age-related changes in children's use of external representations.

This study explored childrens use of external representations. Experiment 1 focused on representations of self: Self-recognition was assessed by a mark test as a function of age (3 vs. 4 years), delay (5 s vs. 3 min), and media (photographs vs. drawings). Four-year-olds outperformed 3-year-olds; children performed better with photographs than drawings; and there was no effect of delay. In Experiment 2, 3- and 4-year-olds used a delayed video image to locate a sticker on themselves (self task) or a stuffed animal (other task). The 2 tasks were positively correlated with age and vocabulary partialed out. Experiment 3 used a search task to assess whether children have particular difficulty using external representations that conflict with their expectations: 3- and 4-year-olds were informed of an objects location verbally or through video: on half of the trials, this information conflicted with childrens initial belief. Three-year-olds performed worse than 4-year-olds on conflict trials, indicating that assessments of self and other understanding may reflect childrens ability to reason about conflicting external representations.

Theory of Mind Through the Ages: Older and Middle-Aged Adults Exhibit More Errors Than Do Younger Adults on a Continuous False Belief Task

Theory of mind (ToM), or the ability to understand mental states, is a fundamental aspect of social cognition. Previous research has documented marked advances in ToM in preschoolers, and declines in ToM in older-aged adults. In the present study, younger (n = 37), middle-aged (n = 20), and older (n = 37) adults completed a continuous false belief task measuring ToM. Middle-aged and older adults exhibited more false belief bias than did younger adults, irrespective of language ability, executive function, processing speed, and memory. The authors conclude that ToM declines from younger to older adulthood, independent of age-related changes to domain-general cognitive functioning.

“I pick you”: the impact of fairness and race on infants’ selection of social partners

By 15 months of age infants are sensitive to violations of fairness norms as assessed via their enhanced visual attention to unfair versus fair outcomes in violation-of-expectation paradigms. The current study investigated whether 15-month-old infants select social partners on the basis of prior fair versus unfair behavior, and whether infants integrate social selections on the basis of fairness with the race of the distributors and recipients involved in the exchange. Experiment 1 demonstrated that after witnessing one adult distribute toys to two recipients fairly (2:2 distribution), and another adult distribute toys to two recipients unfairly (1:3 distribution), Caucasian infants selected fair over unfair distributors when both distributors were Caucasian; however, this preference was not present when the fair actor was Asian and the unfair actor was Caucasian. In Experiment 2, when fairness, the race of the distributor, and the race of the recipients were fully crossed, Caucasian infants’ social selections varied as a function of the race of the recipient advantaged by the unfair distributor. Specifically, infants were more likely to select the fair distributor when the unfair recipient advantaged the Asian (versus the Caucasian) recipient. These findings provide evidence that infants select social partners on the basis of prior fair behavior and that infants also take into account the race of distributors and recipients when making their social selections.

Assessing the role of memory in preschoolers' performance on episodic foresight tasks

A total of 48 preschoolers (ages 3, 4, and 5) received four tasks modelled after prior work designed to assess the development of “episodic foresight”. For each task, children encountered a problem in one room and, after a brief delay, were given the opportunity in a second room to select an item to solve the problem. Importantly, after selecting an item, children were queried about their memory for the problem. Age-related changes were found both in childrens ability to select the correct item and their ability to remember the problem. However, when we controlled for childrens memory for the problem, there were no longer significant age-related changes on the item choice measure. These findings suggest that age-related changes in childrens performance on these tasks are driven by improvements in childrens memory versus improvements in childrens future-oriented thinking or “foresight” per se. Our results have important implications for how best to structure tasks to measure childrens episodic foresight, and also for the relative role of memory in this task and in episodic foresight more broadly.

The importance of discovery in children's causal learning from interventions

Four-year-olds were more accurate at learning causal structures from their own actions when they were allowed to act first and then observe an experimenter act, as opposed to observing first and then acting on the environment. Children who discovered the causal efficacy of events (as opposed to confirming the efficacy of events that they observed another discover) were also more accurate than children who only observed the experimenter act on the environment; accuracy in the confirmation and observation conditions was at similar levels. These data suggest that while children learn from acting on the environment, not all self-generated action produces equivalent causal learning.

The Role of Probability and Intentionality in Preschoolers' Causal Generalizations

Three experiments examined whether preschoolers recognize that the causal properties of objects generalize to new members of the same set given either deterministic or probabilistic data. Experiment 1 found that 3- and 4-year-olds were able to make such a generalization given deterministic data but were at chance when they observed probabilistic information. Five-year-olds reliably generalized in both situations. Experiment 2 found that 4-year-olds could make some probabilistic inferences, particularly when comparing sets that had no efficacy with sets in which some members had efficacy. Children had some difficulty discriminating between completely effective sets and stochastic ones. Experiment 3 examined whether 3- and 4-year-olds could reason about probabilistic data when provided with information about the experimenters beliefs about causal outcomes. Children who were more successful on standard false-belief measures were more likely to respond as if the data were deterministic. These data suggest that childrens probabilistic inferences develop into early elementary school, but preschoolers might have some understanding of probability when reasoning about causal generalization.

Shifting goals: effects of active and observational experience on infants' understanding of higher order goals

Action perception links have been argued to support the emergence of action understanding, but their role in infants’ perception of distal goals has not been fully investigated. The current experiments address this issue. During the development of means-end actions, infants shift their focus from the means of the action to the distal goal. In Experiment One, we evaluated whether this same shift in attention (from the means to the distal goal) when learning to produce multi-step actions is reflected in infants’ perception of others’ means-end actions. Eight-months-old infants underwent active training in means-end action production and their subsequent analysis of an observed means-end action was assessed in a visual habituation paradigm. Infants’ degree of success in the training paradigm was related to their subsequent interpretation of the observed action as directed at the means versus the distal goal. In Experiment Two, observational and control manipulations provided evidence that these effects depended on the infants’ active engagement in the means-end actions. These results suggest that the processes that give rise to means-end structure in infants’ motor behavior also support the emergence of means-end structure in their analysis of others’ goals.