Six-month-olds actively predict others’ goal-directed actions

Understanding a Third-Party Communicative Situation in Korean-Learning Infants

The present study tested 14-month-old monolingual infants (N = 64, 52% female, 75% Korean, and 25% American) in a looking-time task adapted from previous referent identification research. In three experiments, Korean-learning infants watched a speaker, who could only see one of two identical balls, ask a recipient, "gong jom jul-lae?" ("Will you give me Ø ball?" because Korean lacks an article system). They expected the recipient to reach for the ball visible to the speaker, but not the one hidden from her, only when the speaker was introduced separately to facilitate perspective-taking. Korean infants were also found to hold these expectations when the speaker said, "jeo gong jom jul-lae?" ("Will you give me that ball?"), presumably because the added demonstrative "jeo" rendered the speech more informative. A group of American English-learning infants performed similarly, but not as robustly as did their Korean peers, when the speaker requested "Give me that ball." These findings shed new light on how infants use their emergent perspective-taking and language skills to interpret a speaker's intended referent and expand the previous focus on English-learning infants.

The Cognitive Architecture of Infant Attachment

Meta-analytic evidence indicates that the quality of the attachment relationship that infants establish with their primary caregiver has enduring significance for socioemotional and cognitive outcomes. However, the mechanisms by which early attachment experiences contribute to subsequent development remain underspecified. According to attachment theory, early attachment experiences become embodied in the form of cognitive-affective representations, referred to as internal working models (IWMs), that guide future behavior. Little is known, however, about the cognitive architecture of IWMs in infancy. In this article, we discuss significant advances made in the field of infant cognitive development and propose that leveraging insights from this research has the potential to fundamentally shape our understanding of the cognitive architecture of attachment representations in infancy. We also propose that the integration of attachment research into cognitive research can shed light on the role of early experiences, individual differences, and stability and change in infant cognition, as well as open new routes of investigation in cognitive studies, which will further our understanding of human knowledge. We provide recommendations for future research throughout the article and conclude by using our collaborative research as an example.

In praise of folly: flexible goals and human cognition

Humans often pursue idiosyncratic goals that appear remote from functional ends, including information gain. We suggest that this is valuable because goals (even prima facie foolish or unachievable ones) contain structured information that scaffolds thinking and planning. By evaluating hypotheses and plans with respect to their goals, humans can discover new ideas that go beyond prior knowledge and observable evidence. These hypotheses and plans can be transmitted independently of their original motivations, adapted across generations, and serve as an engine of cultural evolution. Here, we review recent empirical and computational research underlying goal generation and planning and discuss the ways that the flexibility of our motivational system supports cognitive gains for both individuals and societies.

Objects in a social world: Infants' object representational capacity limits are shaped by objects' social relevance

Several decades of research have revealed consistent signature limits on infants' ability to represent objects. However, these signature representational limits were established with methods that often removed objects from their most common context. In infants' everyday lives, objects are very often social artifacts: they are the targets of agents' goal-directed actions, communications, and beliefs, and may have social content or relevance themselves. In this chapter, we explore the relationship between infants' object representational capacity limits and their processing of the social world. We review evidence that the social content and context of objects can shift infants' object representational limits. We discuss how taking the social world into account can yield more robust and ecologically valid estimates of infants' early representational capacities.

Can 5-month-old infants consider the perspective of a novel eyeless agent? New evidence for early mentalistic reasoning

Is early reasoning about an agent's knowledge best characterized by a mentalistic stance, a teleological stance, or both? In this research, 5-month-old infants (N = 64, 50% female, 83% White) saw a novel eyeless agent consistently approach object-A as opposed to object-B. Although infants could always see both objects, a screen separated object-B from the agent. When object-B protruded above the screen, infants interpreted the agent's actions as revealing a preference for object-A over object-B. When object-B did not protrude above the screen, however, infants refrained from attributing such a preference: Consistent with mentalistic accounts, they reasoned that the agent's representation of the scene did not include object-B, and they used the agent's incomplete representation, non-egocentrically, to interpret its actions.

Six-month-olds' ability to use linguistic cues when interpreting others' pointing actions

The present research investigated whether six-month-olds who rarely produce pointing actions can detect the object-directedness and communicative function of others' pointing actions when linguistic information is provided. In Experiment 1, infants were randomly assigned to either a novel-word or emotional-vocalization condition. They were first familiarized with an event in which an actor uttered either a novel label (novel-word condition) or exclamatory expression (emotional-vocalization condition) and then pointed to one of two objects. Next, the positions of the objects were switched. During test trials, each infant watched the new-referent event where the actor pointed to the object to which the actor had not pointed before or the old-referent event where the actor pointed to the old object in its new location. Infants in the novel-word condition looked reliably longer at the new-referent event than at the old-referent event, suggesting that they encoded the object-directedness of the actor's point. In contrast, infants in the emotional-vocalization condition showed roughly equal looking times to the two events. To further examine infants' understanding of the communicative aspect of an actor's point using a different communicative context, Experiment 2 used an identical procedure to the novel-word condition in Experiment 1, except there was only one object present during the familiarization trials. When the familiarization trials did not include a contrasting object, we found that the communicative intention of the actor's point could be ambiguous. The infants showed roughly equal looking times during the two test events. The current research suggests that six-month-olds understand the object-directedness and communicative intention of others' pointing when presented with a label, but not when presented with an emotional non-speech vocalization.

Stopping at nothing: Two-year-olds differentiate between interrupted and abandoned goals

Previous research has established that goal tracking emerges early in the first year of life and rapidly becomes increasingly sophisticated. However, it has not yet been shown whether young children continue to update their representations of others' goals over time. The current study investigated this by probing young children's (24- to 30-month-olds; N = 24) ability to differentiate between goal-directed actions that have been halted because the goal was interrupted and those that have been halted because the goal was abandoned. To test whether children are sensitive to this distinction, we manipulated the experimenter's reason for not completing a goal-directed action; his initial goal was either interrupted by an obstacle or abandoned in favor of an alternative. We measured whether children's helping behavior was sensitive to the experimenter's reason for not completing his goal-directed action by recording whether children completed the experimenter's initial goal or the alternative goal. The results showed that children helped to complete the experimenter's initial goal significantly more often after this goal had been interrupted than after it had been abandoned. These results support the hypothesis that children continue to update their representations of others' goals over time by 2 years of age and specifically that they differentiate between abandoned and interrupted goals.

Five-month-old infants attribute inferences based on general knowledge to agents

To make sense of others' actions, we generally consider what information is available to them. This information may come from different sources, including perception and inference. Like adults, young infants track what information agents can obtain through perception: If an agent directly observes an event, for example, young infants expect the agent to have information about it. However, no investigation has yet examined whether young infants also track what information agents can obtain through inference, by bringing to bear relevant general knowledge. Building on the finding that by 4 months of age most infants have acquired the physical rule that wide objects can fit into wide containers but not narrow containers, we asked whether 5-month-olds would expect an agent who was searching for a wide toy hidden in her absence to reach for a wide box as opposed to a narrow box. Infants looked significantly longer when the agent selected the narrow box, suggesting that they expected her (a) to share the physical knowledge that wide objects can fit only into wide containers and (b) to infer that the wide toy must be hidden in the wide box. Three additional conditions supported this interpretation. Together, these results cast doubt on two-system accounts of early psychological reasoning, which claim that infants' early-developing system is too inflexible and encapsulated to integrate inputs from other cognitive processes, such as physical reasoning. Instead, the results support one-system accounts and provide new evidence that young infants' burgeoning psychological-reasoning system is qualitatively similar to that of older children and adults.

14-Month-olds anticipate others' actions based on their belief about an object's identity

Past research has accumulated evidence regarding infants' false-belief understanding, measuring their gaze patterns or active helping behaviors. However, the underlying mechanisms are still debated, specifically, whether young infants can compute that others represent the world under a certain aspect. Such performance requires holding in mind two representations about the same object simultaneously and attributing only one to another person. While 14-month-olds can encode an object under different aspects when forming first-person representations, it is unclear whether infants at this very age could also predict others' behavior based on their beliefs about an object's identity. Here, we investigate this question in a novel eye-tracking-based unexpected-identity task. We measured 14-month-olds' anticipatory looks combined with their looking time, using a violation-of-expectation paradigm. Results show that 14-month-olds look longer to an actor's reach that is incongruent with her false belief about the identity of an object compared to a congruent reach. Furthermore, infants correctly anticipated the actor's reach based on her false belief. Thus, as soon as infants represent dual identities they can integrate them in belief attributions and use them for consequent behavioral predictions. Such data provide evidence for the flexibility of false-belief attributions and support proposals arguing for infants' rich theory-of-mind abilities.

Six-Month-Old Infants Predict Agents' Goal-Directed Actions on Occluded Objects

Infants can infer agents' goals after observing agents' goal-directed actions on objects and can subsequently make predictions about how agents will act on objects in the future. We investigated the representations supporting these predictions. We familiarized 6-month-old infants to an agent who preferentially reached for one of two featurally distinct objects following a cue. At test, the objects were sequentially occluded from the infant in the agent's presence. We asked whether infants could generate action predictions without visual access to the relevant objects by measuring whether infants shifted their gaze to the location of the agent's hidden goal object following the cue. We also examined what infants represented about the hidden objects by removing one of the occluders to reveal either the original hidden object or the unexpected other object and measuring infants' looking time. We found that, even without visual access to the objects, infants made predictive gazes to the location of the agent's occluded goal object, but failed to represent the features of either hidden object. These results suggest that infants make goal-based action predictions when the relevant objects in the scene are occluded, but doing so may come at the expense of maintaining representations of the objects.

How do 3-month-old infants attribute preferences to a human agent?

The current study showed that 3-month-old infants attributed a preference to a human agent, with her face and upper body visible, when she consistently reached for and grasped one of two objects with her bare hand. In contrast, infants did not appear to interpret the agent's same actions of grasping the object as indicative of her preference when it was the only object present or when it hid the other object from her but not from the infants. These results suggest that even from an early age, infants interpret human agents' actions in terms of mental states such as goals and preferences. In light of the current results, mechanisms for early psychological understanding are discussed.

Is the bias for function-based explanations culturally universal? Children from China endorse teleological explanations of natural phenomena

Young children in Western cultures tend to endorse teleological (function-based) explanations broadly across many domains, even when scientifically unwarranted. For instance, in contrast to Western adults, they explicitly endorse the idea that mountains were created for climbing, just like hats were created for warmth. Is this bias a product of culture or a product of universal aspects of human cognition? In two studies, we explored whether adults and children in Mainland China, a highly secular, non-Western culture, show a bias for teleological explanations. When explaining both object properties (Experiment 1) and origins (Experiment 2), we found evidence that they do. Whereas Chinese adults restricted teleological explanations to scientifically warranted cases, Chinese children endorsed them more broadly, extending them across different kinds of natural phenomena. This bias decreased with rising grade level across first, second, and fourth grades. Overall, these data provide evidence that children's bias for teleological explanations is not solely a product of Western Abrahamic cultures. Instead, it extends to other cultures, including the East Asian secular culture of modern-day China. This suggests that the bias for function-based explanations may be driven by universal aspects of human cognition.