Infants generate goal-based action predictions

How do infants and adults process communicative events in real time?

Speech allows humans to communicate and to navigate the social world. By 12 months, infants recognize that speech elicits appropriate responses from others. However, it is unclear how infants process dynamic communicative scenes and how their processing abilities compare with those of adults. Do infants, like adults, process communicative events while the event is occurring or only after being presented with the outcome? We examined 12-month-olds' and adults' eye movements as they watched a Communicator grasp one (target) of two objects. During the test event, the Communicator could no longer reach the objects, so she spoke or coughed to a Listener, who selected either object. Infants' and adults' patterns of looking to the actors and objects revealed that both groups immediately evaluated the Communicator's speech, but not her cough, as communicative and recognized that the Listener should select the target object only when the Communicator spoke. Furthermore, infants and adults shifted their attention between the actors and the objects in very similar ways. This suggests that 12-month-olds can quickly process communicative events as they occur with adult-like accuracy. However, differences in looking reveal that 12-month-olds process slower than adults. This early developing processing ability may allow infants to learn language and acquire knowledge from communicative interactions.

Goal prediction in 2-year-old children with and without autism spectrum disorder: An eye-tracking study

This study examined the predictive reasoning abilities of typically developing (TD) infants and 2-year-old children with autism spectrum disorder (ASD) in an eye-tracking paradigm. Participants watched a video of a goal-directed action in which a human actor reached for and grasped one of two objects. At test, the objects switched locations. Across these events, we measured: visual anticipation of the action outcome with kinematic cues (i.e., a completed reaching behavior); goal prediction of the action outcome without kinematic cues (i.e., an incomplete reach); and latencies to generate predictions across these two tasks. Results revealed similarities in action anticipation across groups when trajectory information regarding the intended goal was present; however, when predicting the goal without kinematic cues, developmental and diagnostic differences became evident. Younger TD children generated goal-based visual predictions, whereas older TD children were not systematic in their visual predictions. In contrast to both TD groups, children with ASD generated location-based predictions, suggesting that their visual predictions may reflect visuomotor perseveration. Together, these results suggest differences in early predictive reasoning abilities. Autism Res 2018, 11: 870-882. © 2018 International Society for Autism Research, Wiley Periodicals, Inc.

LAY SUMMARY

The current study examines the ability to generate visual predictions regarding other people's goal-directed actions, specifically reaching and grasping an object, in infants and children with and without autism spectrum disorder. Results showed no differences in abilities when movement information about a person's goal was evident; however, differences were evident across age and clinical diagnoses when relying on previous knowledge to generate a visual prediction.

Reaching the goal: Active experience facilitates 8-month-old infants' prospective analysis of goal-based actions

From early in development, infants view others' actions as structured by intentions, and this action knowledge may be supported by shared action production/perception systems. Because the motor system is inherently prospective, infants' understanding of goal-directed actions should support predictions of others' future actions, yet little is known about the nature and developmental origins of this ability, specifically whether young infants use the goal-directed nature of an action to rapidly predict future social behaviors and whether their action experience influences this ability. Across three conditions, we varied the level of action experience infants engaged in to determine whether motor priming influenced infants' ability to generate rapid social predictions. Results revealed that young infants accurately generated goal-based visual predictions when they had previously been reaching for objects; however, infants who passively observed a demonstration were less successful. Further analyses showed that engaging the cognitively based prediction system to generate goal-based predictions following motor engagement resulted in slower latencies to predict, suggesting that these smart predictions take more time to deploy. Thus, 8-month-old infants may have motor representations of goal-directed actions, yet this is not sufficient for them to predict others' actions; rather, their own action experience supports the ability to rapidly implement knowledge to predict future behavior.

Limb apraxia and the left parietal lobe

Limb apraxia is a heterogeneous disorder of skilled action and tool use that has long perplexed clinicians and researchers. It occurs after damage to various loci in a densely interconnected network of regions in the left temporal, parietal, and frontal lobes. Historically, a highly classificatory approach to the study of apraxia documented numerous patterns of performance related to two major apraxia subtypes: ideational and ideomotor apraxia. More recently, there have been advances in our understanding of the functional neuroanatomy and connectivity of the left-hemisphere "tool use network," and the patterns of performance that emerge from lesions to different loci within this network. This chapter focuses on the left inferior parietal lobe, and its role in tool and body representation, action prediction, and action selection, and how these functions relate to the deficits seen in patients with apraxia subsequent to parietal lesions. Finally, suggestions are offered for several future directions that will benefit the study of apraxia, including increased attention to research on rehabilitation of this disabling disorder.

Oxytocin promotes attention to social cues regardless of group membership

The social saliency account proposes that oxytocin (OT) plays a major role in modulating attentional shifts toward social cues at early stages of processing. We investigated how OT promotes early attention toward nonsocial and social stimuli and explored differences between in-group- and out-group-related social cues. After participants intranasally self-administered OT or placebo, they were eye-tracked while observing a nonsocial and social cues that were assigned to the in- or out-group by a minimal group paradigm. Participants under placebo did not differ in their fixation durations between stimuli, whereas participants administered OT increased gaze durations toward social but not nonsocial stimuli. In this early stage of processing, no in-group bias occurred: in-group- and out-group-related social cues were fixated equally long. These findings support that OT works by a simple illumination of social cues that seem to be processed regardless of social identity aspects at early stages of attention.

Structure Mapping for Social Learning

Analogical reasoning is a foundational tool for human learning, allowing learners to recognize relational structures in new events and domains. Here I sketch some grounds for understanding and applying analogical reasoning in social learning. The social world is fundamentally characterized by relations between people, with common relational structures-such as kinships and social hierarchies-forming social units that dictate social behaviors. Just as young learners use analogical reasoning for learning relational structures in other domains-spatial relations, verbs, relational categories-analogical reasoning ought to be a useful cognitive tool for acquiring social relations and structures.

Eye tracking uncovered great apes' ability to anticipate that other individuals will act according to false beliefs

Using a novel eye-tracking test, we recently showed that great apes anticipate that other individuals will act according to false beliefs. This finding suggests that, like humans, great apes understand others' false beliefs, at least in an implicit way. One key question raised by our study is why apes have passed our tests but not previous ones. In this article, we consider this question by detailing the development of our task. We considered 3 major differences in our task compared with the previous ones. First, we monitored apes' eye movements, and specifically their anticipatory looks, to measure their predictions about how agents will behave. Second, we adapted our design from an anticipatory-looking false belief test originally developed for human infants. Third, we developed novel test scenarios that were specifically designed to capture the attention of our ape participants. We then discuss how each difference may help explain differences in performance on our task and previous ones, and finally propose some directions for future studies.

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.

Why (and how) should we study the interplay between emotional arousal, Theory of Mind, and inhibitory control to understand moral cognition?

Findings in the field of experimental psychology and cognitive neuroscience have shed new light on our understanding of the psychological and biological bases of morality. Although a lot of attention has been devoted to understanding the processes that underlie complex moral dilemmas, attempts to represent the way in which individuals generate moral judgments when processing basic harmful actions are rare. Here, we will outline a model of morality which proposes that the evaluation of basic harmful actions relies on complex interactions between emotional arousal, Theory of Mind (ToM) capacities, and inhibitory control resources. This model makes clear predictions regarding the cognitive processes underlying the development of and ability to generate moral judgments. We draw on data from developmental and cognitive psychology, cognitive neuroscience, and psychopathology research to evaluate the model and propose several conceptual and methodological improvements that are needed to further advance our understanding of moral cognition and its development.

The effects of an action's "age-of-acquisition" on action-sentence processing

How does our brain allow us comprehend abstract/symbolic descriptions of human action? Whereas past research suggested that processing action language relies on sensorimotor brain regions, recent work suggests that sensorimotor activation depends on participants' task goals, such that focusing on abstract (vs. concrete) aspects of an action activates "default mode network" (rather than sensorimotor) regions. Following a Piagetian framework, we hypothesized that for actions acquired at an age wherein abstract/symbolic cognition is fully-developed, even when participants focus on the concrete aspects of an action, they should retrieve abstract-symbolic mental representations. In two studies, participants processed the concrete (i.e., "how") and abstract (i.e., "why") aspects of late-acquired and early-acquired actions. Consistent with previous research, focusing on the abstract (vs. concrete) aspects of an action resulted in greater activation in the "default mode network". Importantly, the activation in these regions was higher when processing later-acquired (vs. earlier acquired) actions-also when participants' goal was to focus on the concrete aspects of the action. We discuss the implications of the current findings to research on the involvement of concrete representations in abstract cognition.

Predictive action tracking without motor experience in 8-month-old infants

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Can infants predictively track the kinematics of actions outside their motor repertoire?

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Pre-walking infants predictively tracked upright, but not inverted stepping actions.

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Sensorimotor cortex was activated more when infants observed upright stepping actions.

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Motor experience is not necessary for predictive tracking of action kinematics.

A popular idea in cognitive neuroscience is that to predict others’ actions, observers need to map those actions onto their own motor repertoire. If this is true, infants with a relatively limited motor repertoire should be unable to predict actions with which they have no previous motor experience. We investigated this idea by presenting pre-walking infants with videos of upright and inverted stepping actions that were briefly occluded from view, followed by either a correct (time-coherent) or an incorrect (time-incoherent) continuation of the action (Experiment 1). Pre-walking infants looked significantly longer to the still frame after the incorrect compared to the correct continuations of the upright, but not the inverted stepping actions. This demonstrates that motor experience is not necessary for predictive tracking of action kinematics. In a follow-up study (Experiment 2), we investigated sensorimotor cortex activation as a neural indication of predictive action tracking in another group of pre-walking infants. Infants showed significantly more sensorimotor cortex activation during the occlusion of the upright stepping actions that the infants in Experiment 1 could predictively track, than during the occlusion of the inverted stepping actions that the infants in Experiment 1 could not predictively track. Taken together, these findings are inconsistent with the idea that motor experience is necessary for the predictive tracking of action kinematics, and suggest that infants may be able to use their extensive experience with observing others’ actions to generate real-time action predictions.

From faces to hands: Changing visual input in the first two years

Human development takes place in a social context. Two pervasive sources of social information are faces and hands. Here, we provide the first report of the visual frequency of faces and hands in the everyday scenes available to infants. These scenes were collected by having infants wear head cameras during unconstrained everyday activities. Our corpus of 143hours of infant-perspective scenes, collected from 34 infants aged 1month to 2years, was sampled for analysis at 1/5Hz. The major finding from this corpus is that the faces and hands of social partners are not equally available throughout the first two years of life. Instead, there is an earlier period of dense face input and a later period of dense hand input. At all ages, hands in these scenes were primarily in contact with objects and the spatio-temporal co-occurrence of hands and faces was greater than expected by chance. The orderliness of the shift from faces to hands suggests a principled transition in the contents of visual experiences and is discussed in terms of the role of developmental gates on the timing and statistics of visual experiences.

Action perception in infancy: the plasticity of 7-month-olds' attention to grasping actions

The present study investigates the plasticity of 7-month-old infants' orienting of attention during their perception of grasping actions. Previous research has shown that when infants observe a grasping hand, they shift their attention in line with the grasping direction, which is indicated by a reliable priming effect in this direction. The mechanisms behind this priming effect are largely unknown, and it is unclear how malleable this priming effect is with respect to a brief exposure to novel action-target contingencies. In a spatial-cueing paradigm, we presented a series of training trials prior to a series of test trials. These training sequences significantly modulated infants' attention. This suggests that action perception, when assessed through shifts of attention, is not solely based on the infants' grasping experience but quickly adapts to context-specific observed regularities.

Infants' Understanding of Object-Directed Action: An Interdisciplinary Synthesis

Recognizing that the object-directed actions of others are governed by goals and intentions is a crucial component of human interaction. These actions often occur rapidly and without explanation, yet we learn from and predict the actions of others with remarkable speed and accuracy, even during the first year of life. This review paper will serve as a bridge between several disparate literatures that, we suggest, can each contribute to our understanding of how infants interpret action. Specifically, we provide a review not just of research on infant goal attribution per se, but also incorporate findings from studies on the mirror neuron system and infant object cognition. The integration of these various research approaches allows for a novel construal of the extents and limits of early goal attribution – one in which the importance of the entire action context is considered – and points to specific future research directions.

Relations between infants' emerging reach-grasp competence and event-related desynchronization in EEG

Recent reports of similar patterns of brain electrical activity (electroencephalogram: EEG) during action execution and observation, recorded from scalp locations over motor-related regions in infants and adults, have raised the possibility that two foundational abilities--controlling one's own intentional actions and perceiving others' actions--may be integrally related during ontogeny. However, to our knowledge, there are no published reports of the relations between developments in motor skill (i.e. recording actual motor skill performance) and EEG during both action execution and action observation. In the present study we collected EEG from 21 9-month-olds who were given opportunities to reach for toys and who also observed an experimenter reach for toys. Event-related desynchronization (ERD) was computed from the EEG during the reaching events. We assessed infants' reaching-grasping competence, including reach latency, errors, preshaping of the hand, and bimanual reaches, and found that desynchronization recorded in scalp electrodes over motor-related regions during action observation was associated with action competence during execution. Infants who were more competent reachers, compared to less competent reachers, exhibited greater ERD while observing reaching-grasping. These results provide initial evidence for an early emerging neural system integrating one's own actions with the perception of others' actions.

Humans but Not Chimpanzees Vary Face-Scanning Patterns Depending on Contexts during Action Observation

Human and nonhuman primates comprehend the actions of other individuals by detecting social cues, including others’ goal-directed motor actions and faces. However, little is known about how this information is integrated with action understanding. Here, we present the ontogenetic and evolutionary foundations of this capacity by comparing face-scanning patterns of chimpanzees and humans as they viewed goal-directed human actions within contexts that differ in whether or not the predicted goal is achieved. Human adults and children attend to the actor’s face during action sequences, and this tendency is particularly pronounced in adults when observing that the predicted goal is not achieved. Chimpanzees rarely attend to the actor’s face during the goal-directed action, regardless of whether the predicted action goal is achieved or not. These results suggest that in humans, but not chimpanzees, attention to actor’s faces conveying referential information toward the target object indicates the process of observers making inferences about the intentionality of an action. Furthermore, this remarkable predisposition to observe others’ actions by integrating the prediction of action goals and the actor’s intention is developmentally acquired.

Emotional experience in music fosters 18-month-olds' emotion-action understanding: a training study

We examine whether emotional experiences induced via music-making promote infants' use of emotional cues to predict others' action. Fifteen-month-olds were randomly assigned to participate in interactive emotion training either with or without musical engagement for three months. Both groups were then re-tested with two violation-of-expectation paradigms respectively assessing their sensitivity to some expressive features in music and understanding of the link between emotion and behaviour in simple action sequences. The infants who had participated in music, but not those who had not, were surprised by music-face inconsistent displays and were able to interpret an agent's action as guided by her expressed emotion. The findings suggest a privileged role of musical experience in prompting infants to form emotional representations, which support their understanding of the association between affective states and action.

Think fast! The relationship between goal prediction speed and social competence in infants

Skilled social interactions require knowledge about others' intentions and the ability to implement this knowledge in real-time to generate appropriate responses to one's partner. Young infants demonstrate an understanding of other people's intentions (e.g. Woodward, Sommerville, Gerson, Henderson & Buresh, 2009), yet it is not until the second year that infants seem to master the real-time implementation of their knowledge during social interactions (e.g. Warneken & Tomasello, 2007). The current study investigates the possibility that developments in social competence during the second year are related to increases in the speed with which infants can employ their understanding of others' intentions. Twenty- to 22-month-old infants (N = 23) viewed videos of goal-directed actions on a Tobii eye-tracker and then engaged in an interactive perspective-taking task. Infants who quickly and accurately anticipated another person's future behavior in the eye-tracking task were more successful at taking their partner's perspective in the social interaction. Success on the perspective-taking task was specifically related to the ability to correctly predict another person's intentions. These findings highlight the importance of not only being a 'smart' social partner but also a 'fast' social thinker.

Engagement: Looking beyond the mirror to understand action understanding

In this paper, we argue that the current focus on mirroring as the route to explaining the development of action understanding is misleading and problematic. It facilitates a fundamentally spectatorial stance, ignoring engagement and dialogue; it focuses on similarity between self and other and neglects difference; and it succumbs to the static terminology of mechanism rather than a dynamic language of process. Contrary to this view, dialogic exchanges are evident from the start of life, revealing infants' ability to engage with and respond appropriately to actions that are outside their own motor repertoire. We suggest that engagement rather than mirroring better accounts for many current findings in action understanding. The neurological evidence to date shows that action perception involves a process of continuous synchronization and change, suggesting that it might be more fruitful for research and theory to look beyond mirroring and instead adopt dynamic processual explanations of action understanding within interaction.

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.

A developmental perspective on action and social cognition

The target article argues that developmental processes are key to understanding the mirror neuron system, yet neglects several bodies of developmental research that are informative for doing so. Infants' actions and action understanding are structured by goals, and the former lends structure to the latter. Evaluating the origins and functions of mirror neurons depends on integrating investigations of neural, social-cognitive and motor development.

The importance of witnessed agency in chimpanzee social learning of tool use

Social learning refers to individuals learning from others, including information gained through indirect social influences, such as the results of others' actions and changes in the physical environment. One method to determine the relative influence of these varieties of information is the 'ghost display', in which no model is involved, but subjects can watch the results that a model would produce. Previous research has shown mixed success by chimpanzees (Pan troglodytes) learning from ghost displays, with some studies suggesting learning only in relatively simple tasks. To explore whether the failure of chimpanzees to learn from a ghost display may be due to neophobia when tested singly or a requirement for more detailed information for complex tasks, we presented ghost displays of a tool-use task to chimpanzees in their home social groups. Previous tests have revealed that chimpanzees are unable to easily solve this tool-use task asocially, or learn from ghost displays when tested singly, but can learn after observing conspecifics in a group setting. In the present study, despite being tested in a group situation, chimpanzees still showed no success in solving the task via trial-and-error learning, in a baseline condition, nor in learning the task from the ghost display. Simply being in the presence of their group mates and being shown the affordances of the task was not sufficient to encourage learning. Following this, in an escalating series of tests, we examined the chimpanzees' ability to learn from a demonstration by models with agency: (1) a human; (2) video footage of a chimpanzee; (3) a live chimpanzee model. In the first two of these 'social' conditions, subjects showed limited success. By the end of the final open diffusion phase, which was run to determine whether this new behavior would be transmitted among the group after seeing a successful chimpanzee use the task, 83% of chimpanzees were now successful. This confirmed a marked overall effect of observing animate conspecific modeling, in contrast to the ghost condition. This article is part of a Special Issue entitled: insert SI title.

Infants' online perception of give-and-take interactions

This research investigated infants' online perception of give-me gestures during observation of a social interaction. In the first experiment, goal-directed eye movements of 12-month-olds were recorded as they observed a give-and-take interaction in which an object is passed from one individual to another. Infants' gaze shifts from the passing hand to the receiving hand were significantly faster when the receiving hand formed a give-me gesture relative to when it was presented as an inverted hand shape. Experiment 2 revealed that infants' goal-directed gaze shifts were not based on different affordances of the two receiving hands. Two additional control experiments further demonstrated that differences in infants' online gaze behavior were not mediated by an attentional preference for the give-me gesture. Together, our findings provide evidence that properties of social action goals influence infants' online gaze during action observation. The current studies demonstrate that infants have expectations about well-formed object transfer actions between social agents. We suggest that 12-month-olds are sensitive to social goals within the context of give-and-take interactions while observing from a third-party perspective.

Great Apes Generate Goal-Based Action Predictions

To examine great apes’ on-line prediction of other individuals’ actions, we used an eye-tracking technique and an experimental paradigm previously used to test human infants. Twenty-two great apes, including bonobos, chimpanzees, and orangutans, were familiarized to movie clips of a human hand reaching to grasp one of two objects. Then the objects’ locations were swapped, and in the test event, the hand made an incomplete reach between the objects. In a control condition, a mechanical claw performed the same actions. The apes predictively looked at the familiarized goal object rather than the familiarized location when viewing the hand action in the test event. However, they made no prediction when viewing the claw action. These results are similar to those reported previously for human infants, and predictive looking did not differ among the three species of great apes. Thus, great apes make on-line goal-based predictions about the actions of other individuals; this skill is not unique to humans but is shared more widely among primates.

Making smart social judgments takes time: infants' recruitment of goal information when generating action predictions

Previous research has shown that young infants perceive others' actions as structured by goals. One open question is whether the recruitment of this understanding when predicting others' actions imposes a cognitive challenge for young infants. The current study explored infants' ability to utilize their knowledge of others' goals to rapidly predict future behavior in complex social environments and distinguish goal-directed actions from other kinds of movements. Fifteen-month-olds (N = 40) viewed videos of an actor engaged in either a goal-directed (grasping) or an ambiguous (brushing the back of her hand) action on a Tobii eye-tracker. At test, critical elements of the scene were changed and infants' predictive fixations were examined to determine whether they relied on goal information to anticipate the actor's future behavior. Results revealed that infants reliably generated goal-based visual predictions for the grasping action, but not for the back-of-hand behavior. Moreover, response latencies were longer for goal-based predictions than for location-based predictions, suggesting that goal-based predictions are cognitively taxing. Analyses of areas of interest indicated that heightened attention to the overall scene, as opposed to specific patterns of attention, was the critical indicator of successful judgments regarding an actor's future goal-directed behavior. These findings shed light on the processes that support “smart” social behavior in infants, as it may be a challenge for young infants to use information about others' intentions to inform rapid predictions.

Understanding action with the motor system

We challenge Cook et al.'s claim about the vagueness of the notion of action understanding in relation with mirror neurons. We show the multidimensional nature of action understanding and provide a definition of motor-based action understanding, shedding new light on the various components of action understanding and on their relationship. Finally, we propose an alternative perspective on the origin of mirror neurons, stressing the necessity to abandon the dichotomy between genetic and associative hypotheses.

What are you doing? How active and observational experience shape infants' action understanding

From early in life, infants watch other people's actions. How do young infants come to make sense of actions they observe? Here, we review empirical findings on the development of action understanding in infancy. Based on this review, we argue that active action experience is crucial for infants' developing action understanding. When infants execute actions, they form associations between motor acts and the sensory consequences of these acts. When infants subsequently observe these actions in others, they can use their motor system to predict the outcome of the ongoing actions. Also, infants come to an understanding of others' actions through the repeated observation of actions and the effects associated with them. In their daily lives, infants have plenty of opportunities to form associations between observed events and learn about statistical regularities of others' behaviours. We argue that based on these two forms of experience-active action experience and observational experience-infants gradually develop more complex action understanding capabilities.

Mirroring and the development of action understanding

The discovery of mirror neurons in the monkey motor cortex has inspired wide-ranging hypotheses about the potential relationship between action control and social cognition. In this paper, we consider the hypothesis that this relationship supports the early development of a critical aspect of social understanding, the ability to analyse others' actions in terms of goals. Recent investigations of infant action understanding have revealed rich connections between motor development and the analysis of goals in others' actions. In particular, infants' own goal-directed actions influence their analysis of others' goals. This evidence indicates that the cognitive systems that drive infants' own actions contribute to their analysis of goals in others' actions. These effects occur at a relatively abstract level of analysis both in terms of the structure infants perceive in others' actions and relevant structure in infants' own actions. Although the neural bases of these effects in infants are not yet well understood, current evidence indicates that connections between action production and action perception in infancy involve the interrelated neural systems at work in generating planned, intelligent action.

Labels Facilitate Infants' Comparison of Action Goals

Understanding the actions of others depends on the insight that these actions are structured by intentional relations. In a number of conceptual domains, comparison with familiar instances has been shown to support children's and adults' ability to discern the relational structure of novel instances. Recent evidence suggests that this process supports infants' analysis of others' goal-directed actions (Gerson & Woodward, 2012). The current studies evaluated whether labeling, which has been shown to support relational learning in other domains, also supports infants' sensitivity to the goal structure of others' actions. Ten-month-old infants observed events in which a familiar action, grasping, was aligned (simultaneously presented) with a novel tool use action, and both actions were accompanied by a matched label. Following this training, infants responded systematically to the goal structure of the tool use actions in a goal imitation paradigm. In control conditions, when the aligned actions were accompanied by non-word vocalizations, or when labeling occurred without aligned actions, infants did not respond systematically to the tool use action. These findings indicate that labels supported infants' comparison of the aligned actions, and this comparison facilitated their understanding of the novel action as goal-directed.

Probabilistic perception, empathy, and dynamic homeostasis: insights in autism spectrum disorders and conduct disorders

Homeostasis is not a permanent and stable state but instead results from conflicting forces. Therefore, infants have to engage in dynamic exchanges with their environment, in biological, cognitive, and affective domains. Empathy is an adaptive response to these environmental challenges, which contributes to reaching proper dynamic homeostasis and development. Empathy relies on implicit interactive processes, namely probabilistic perception and synchrony, which will be reviewed in the article. If typically-developed neonates are fully equipped to automatically and synchronously interact with their human environment, conduct disorders (CD) and autism spectrum disorders (ASD) present with impairments in empathetic communication, e.g., emotional arousal and facial emotion processing. In addition sensorimotor resonance is lacking in ASD, and emotional concern and semantic empathy are impaired in CD with Callous-Unemotional traits.

Goal representation in the infant brain

It is well established that, from an early age, human infants interpret the movements of others as actions directed towards goals. However, the cognitive and neural mechanisms which underlie this ability are hotly debated. The current study was designed to identify brain regions involved in the representation of others' goals early in development. Studies with adults have demonstrated that the anterior intraparietal sulcus (aIPS) exhibits repetition suppression for repeated goals and a release from suppression for new goals, implicating this specific region in goal representation in adults. In the current study, we used a modified paired repetition suppression design with 9-month-old infants to identify which cortical regions are suppressed when the infant observes a repeated goal versus a new goal. We find a strikingly similar response pattern and location of activity as had been reported in adults; the only brain region displaying significant repetition suppression for repeated goals and a release from suppression for new goals was the left anterior parietal region. Not only does our data suggest that the left anterior parietal region is specialized for representing the goals of others' actions from early in life, this demonstration presents an opportunity to use this method and design to elucidate the debate over the mechanisms and cues which contribute to early action understanding.

Belief-based action prediction in preverbal infants

Successful mindreading entails both the ability to think about what others know or believe, and to use this knowledge to generate predictions about how mental states will influence behavior. While previous studies have demonstrated that young infants are sensitive to others' mental states, there continues to be much debate concerning how to characterize early theory of mind abilities. In the current study, we asked whether 6-month-old infants appreciate the causal role that beliefs play in action. Specifically, we tested whether infants generate action predictions that are appropriate given an agent's current belief. We exploited a novel, neural indication of action prediction: motor cortex activation as measured by sensorimotor alpha suppression, to ask whether infants would generate differential predictions depending on an agent's belief. After first verifying our paradigm and measure with a group of adult participants, we found that when an agent had a false belief that a ball was in the box, motor activity indicated that infants predicted she would reach for the box, but when the agent had a false belief that a ball was not in the box, infants did not predict that she would act. In both cases, infants based their predictions on what the agent, rather than the infant, believed to be the case, suggesting that by 6months of age, infants can exploit their sensitivity to other minds for action prediction.

Infants' goal anticipation during failed and successful reaching actions

The ability to interpret and predict the actions of others is crucial to social interaction and to social, cognitive, and linguistic development. The current study provided a strong test of this predictive ability by assessing (1) whether infants are capable of prospectively processing actions that fail to achieve their intended outcome, and (2) how infants respond to events in which their initial predictions are not confirmed. Using eye tracking, 8-month-olds, 10-month-olds, and adults watched an actor repeatedly reach over a barrier to either successfully or unsuccessfully retrieve a ball. Ten-month-olds and adults produced anticipatory looks to the ball, even when the action was unsuccessful and the actor never achieved his goal. Moreover, they revised their initial predictions in response to accumulating evidence of the actor's failure. Eight-month-olds showed anticipatory looking only after seeing the actor successfully grasp and retrieve the ball. Results support a flexible, prospective social information processing ability that emerges during the first year of life.

Atypical monitoring and responsiveness to goal-directed gaze in autism spectrum disorder

We hypothesized that difficulty in understanding the goals of others' actions in autism spectrum disorder (ASD) might be linked to a diminished attention and responsivity to relevant social cues. Using an eye-tracking paradigm, we investigated how 24 children with ASD and 24 matched children without ASD responded to the observation of uncompleted actions without a clear target (neutral condition) versus a condition in which the actor's gaze direction indicated the target of the actions (head-turning condition). Children without ASD significantly increased their attention to the actor's face and to the action's target in the head-turning condition compared to the neutral condition, while this was not the case in the ASD group. Overall, our findings suggest a diminished monitoring and responsivity to social cues signalling goal-directedness, which might impact on the ability to understand other's action goals in young children with ASD.