Recent studies in developmental psychology have found evidence to suggest that there exists an innate system that accounts for the possibilities of early infant imitation and the existence of phantom limbs in cases of congenital absence of limbs. These results challenge traditional assumptions about the status and development of the body schema and body image, and about the nature of the translation process between perceptual experience and motor ability. Merleau-Ponty, who was greatly influenced by his study of developmental psychology, and whose phenomenology of perception was closely tied to the concept of the body schema, accepted these traditional assumptions. They also informed his philosophical conclusions concerning the experience of self and others. We re-examine issues involved in understanding self and others in light of the more recent research in developmental psychology. More specifically our re-examination challenges a number of Merleau-Ponty’s conclusions and suggests, in contrast, that the newborn infant is capable of a rudimentary differentiation between self and non-self.
The ability of 9-month-old infants to imitate simple actions with novel objects was investigated. Both immediate and deferred imitation were tested, the latter by interposing a 24-hour delay between the stimulus-presentation and response periods. The results provide evidence for both immediate and deferred imitation; moreover, imitative responding was not significantly dampened by the 24-hour delay. The findings demonstrate that there exists some underlying capacity for deferring imitation of certain acts well under 1 year of age, and thus that this ability does not develop in a stagelike step function at about 18–24 months as commonly predicted. These findings also show that imitation in early infancy can span wide enough delays to be of potential service in social development; actions on novel objects that are observed one day can be stored by the child and repeated the next day. The study of deferred imitation provides a largely untapped method for investigating the nature and development of recall memory in the preverbal child.
Studies indicate that infants in our culture are exposed to significant amounts of TV, often as a baby-sitting strategy by busy caretakers. The question arises whether TV viewing merely presents infants with a salient collection of moving patterns or whether they will readily pick up information depicted in this 2-D representation and incorporate it into their own behavior. Can infants “understand” the content of television enough to govern their real-world behavior accordingly? One way to explore this question is to present a model via television for infants to imitate. Infants’ ability to imitate TV models was explored at 2 ages, 14 and 24 months, under conditions of immediate and deferred imitation. In deferred imitation, infants were exposed to a TV depiction of an adult manipulating a novel toy in a particular way but were not presented with the real toy until the next day. The results showed significant imitation at both ages, and furthermore showed that even the youngest group imitated after the 24-hour delay. The finding of deferred imitation of TV models has social and policy implications, because it suggests that TV viewing in the home could potentially affect infant behavior and development more than heretofore contemplated. The results also add to a growing body of literature on prelinguistic representational capacities. They do so in the dual sense of showing that infants can relate 2-D representations to their own actions on real objects in 3-D space, and moreover that the information picked up through TV can be internally represented over lengthy delays before it is used to guide the real-world action.
How do infants and young children learn about the causal structure of the world around them? In 4 experiments we investigate whether young children initially give special weight to the outcomes of goal-directed interventions they see others perform and use this to distinguish correlations from genuine causal relations—observational causal learning. In a new 2-choice procedure, 2- to 4-year-old children saw 2 identical objects (potential causes). Activation of 1 but not the other triggered a spatially remote effect. Children systematically intervened on the causal object and predictively looked to the effect. Results fell to chance when the cause and effect were temporally reversed, so that the events were merely associated but not causally related. The youngest children (24- to 36-month-olds) were more likely to make causal inferences when covariations were the outcome of human interventions than when they were not. Observational causal learning may be a fundamental learning mechanism that enables infants to abstract the causal structure of the world.
causal learning; imitation; social learning; action representation; predictive looking
Long-term recall memory was assessed using a nonverbal method requiring subjects to reenact a past event from memory (deferred imitation). A large sample of infants (N = 192), evenly divided between 14- and 16-months old, was tested across two experiments. A delay of 2 months was used in Experiment 1 and a delay of 4 months in Experiment 2. In both experiments two treatment groups were used, In one treatment group, motor practice (immediate imitation) was allowed before the delay was imposed; in the other group, subjects were prevented from motor practice before the delay. Age-matched control groups were used lo assess the spontaneous production of the target acts in the absence of exposure to the model in both experiments. The results demonstrated significant deferred imitation for both treatment groups at both delay intervals, and moreover showed that infants retained and imitated multiple acts. These findings suggest that infants have a nonverbal declarative memory system that supports the recall of past events across long-term delays. The implications of these findings for the multiple memory system debate in cognitive science and neuroscience and for theories of infantile amnesia are considered.
There has been a revolution in our understanding of infant and toddler cognition that promises to have far-reaching implications for our understanding of communicative and linguistic development. Four empirical findings that helped to prompt this change in theory are analyzed: (a) Intermodal coordination—newborns operate with multimodal information, recognizing equivalences in information across sensory-modalities; (b) Imitation—newborns imitate the lip and tongue movements they see others perform; (c) Memory—young infants form long-lasting representations of perceived events and use these memories to generate motor productions after lengthy delays in novel contexts; (d) Theory of mind—by 18 months of age toddlers have adopted a theory of mind, reading below surface behavior to the goals and intentions in people's actions. This paper examines three views currently being offered in the literature to replace the classical framework of early cognitive development: modularity-nativism, connectionism, and theory-theory. Arguments are marshaled to support the “theory-theory” view. This view emphasizes a combination of innate structure and qualitative reorganization in children's thought based on input from the people and things in their culture. It is suggested that preverbal cognition forms a substrate for language acquisition and that analyzing cognition may enhance our understanding of certain disorders of communication.
Intermodal coordination; Imitation; Memory; Theory of mind; Representation; Language acquisition; Face perception
A foundational aspect of early social-emotional development is the ability to detect and respond to the actions of others who are coordinating their behavior with that of the self. Behavioral work in this area has found that infants show particular preferences for adults who are imitating them rather than adults who are carrying out noncontingent or mismatching actions. Here we explore the neural processes related to this tendency of infants to prefer others who act like the self. EEG was recorded from 14-month-olds while they were observing actions which either matched or mismatched the action the infant had just executed. Desynchronization of the EEG mu rhythm was greater when infants observed an action that matched their own most recently executed action. This effect was strongest immediately prior to the culmination of the goal of the observed action, which is consistent with recent ideas about the predictive nature of brain responses during action observation.
EEG; mu rhythm; imitation; perception-action; infant
Human infants rapidly learn new skills and customs via imitation, but the neural linkages between action perception and production are not well understood. Neuroscience studies in adults suggest that a key component of imitation–identifying the corresponding body part used in the acts of self and other–has an organized neural signature. In adults, perceiving someone using a specific body part (e.g., hand vs. foot) is associated with activation of the corresponding area of the sensory and/or motor strip in the observer’s brain–a phenomenon called neural somatotopy. Here we examine whether preverbal infants also exhibit somatotopic neural responses during the observation of others’ actions. 14-month-old infants were randomly assigned to watch an adult reach towards and touch an object using either her hand or her foot. The scalp electroencephalogram (EEG) was recorded and event-related changes in the sensorimotor mu rhythm were analyzed. Mu rhythm desynchronization was greater over hand areas of sensorimotor cortex during observation of hand actions and was greater over the foot area for observation of foot actions. This provides the first evidence that infants’ observation of someone else using a particular body part activates the corresponding areas of sensorimotor cortex. We hypothesize that this somatotopic organization in the developing brain supports imitation and cultural learning. The findings connect developmental cognitive neuroscience, adult neuroscience, action representation, and behavioral imitation.
Theory of mind requires belief- and desire-understanding. Event-related brain potential (ERP) research on belief- and desire-reasoning in adults found mid-frontal activations for both desires and beliefs, and selective right-posterior activations only for beliefs. Developmentally, children understand desires before beliefs; thus, a critical question concerns whether neural specialization for belief-reasoning exists in childhood or develops later. Neural activity was recorded as 7- and 8-year-olds (N = 18) performed the same diverse-desires, diverse-beliefs, and physical control tasks used in a previous adult ERP study. Like adults, mid-frontal scalp activations were found for belief- and desire-reasoning. Moreover, analyses using correct trials alone yielded selective right-posterior activations for belief-reasoning. Results suggest developmental links between increasingly accurate understanding of complex mental states and neural specialization supporting this understanding.
Two experiments examine preschool-aged children’s ability to anticipate physiological states of the self. One hundred and eight 3-, 4-, and 5-year-olds were presented with stories and pictorial scenes designed to evoke thought about future states such as thirst, cold, and hunger. They were asked to imagine themselves in these scenarios and to choose one item from a set of three that they would need. Only one of the items could be used to address the future state. In both experiments, developmental differences were obtained for correct item choices and types of verbal explanations. In Experiment 2, the performance of the 3- and 4-year-olds was negatively affected by introducing items that were semantically associated with the scenarios but did not address the future state, whereas the 5-year-olds’ performance was not. Results are discussed with respect to children’s understanding of the future, theory of mind, and inhibitory control skills.
Cognitive development; Future thinking; Self; Explanations
Using a gaze-following task, the authors assessed whether self-experience with the view-obstructing properties of blindfolds influenced infants’ understanding of this effect in others. In Experiment 1, 12-month-olds provided with blindfold self-experience behaved as though they understood that a person wearing a blindfold cannot see. When a blindfolded adult turned to face an object, these infants gaze followed significantly less than control infants who had either (a) seen and felt the blindfold but whose view had not been obstructed by it or (b) experienced a windowed blindfold through which they could see. In Experiment 2, 18-month-olds experienced either (a) a trick blindfold that looked opaque but could be seen through, (b) an opaque blindfold, or (c) baseline familiarization. Infants receiving trick-blindfold experience now followed a blindfolded adult’s gaze significantly more than controls. The authors propose 3 mechanisms underlying infants’ capacity to use self-experience as a framework for understanding the visual perception of others.
social cognition; gaze following; training experience; theory of mind; intention
This report describes a case study of the development of an infant with autism who was observed closely by professionals from birth and to whom a comprehensive psychological evaluation was administered at approximately 1 and 2 years of age. During the first 6 months of life, this infant displayed difficulties in oral motor coordination and muscle tone that fluctuated between hypotonia and hypertonia. He startled easily, had poor state regulation, and was hypersensitive to touch. Notably, however, during the first 6 months, this infant vocalized and responded socially to others by smiling and cooing. During the second half of the first year, he continued to demonstrate diffuse sensorimotor difficulties and diminished oral motor control. Hypersensitivity now extended to a wider range of stimuli. He had problems in sleep regulation. Motor stereotypies, including rocking, head banging, and toe walking, were observed. Difficulties in the domain of social interaction began to emerge during the second 6 months, including poor eye contact, failure to engage in imitative games, and lack of imitative vocal responses. By a little over 1 year of age, this infant met diagnostic criteria for autism based on the Autism Diagnostic Interview. There were several domains in which this toddler with autism did not show impairments. In the areas of immediate memory for actions, working memory, response inhibition, and speech perception, this 1-year old with autism displayed no evidence of significant impairment on the tests administered. This case study offers clues regarding the nature of autism at its earliest stages. Understanding early development in autism will be important for developing early screening and diagnostic tools.
Infants’ development of speech begins with a language-universal pattern of production that eventually becomes language specific. One mechanism contributing to this change is vocal imitation. The present study was undertaken to examine developmental change in infants’ vocalizations in response to adults’ vowels at 12, 16, and 20 weeks of age and test for vocal imitation. Two methodological aspects of the experiment are noteworthy: (a) three different vowel stimuli (/a/, /i/, and /u/) were videotaped and presented to infants by machine so that the adult model could not artifactually influence infant utterances, and (b) infants’ vocalizations were analyzed both physically, using computerized spectrographic techniques, and perceptually by trained phoneticians who transcribed the utterances. The spectrographic analyses revealed a developmental change in the production of vowels. Infants’ vowel categories become more separated in vowel space from 12 to 20 weeks of age. Moreover, vocal imitation was documented. Infants listening to a particular vowel produced vocalizations resembling that vowel. A hypothesis is advanced extending Kuhl’s native language magnet (NLM) model to encompass infants’ speech production. It is hypothesized that infants listening to ambient language store perceptually derived representations of the speech sounds they hear which in turn serve as targets for the production of speech utterances. NLM unifies previous findings on the effects of ambient language experience on infants’ speech perception and the findings reported here that short-term laboratory experience with speech is sufficient to influence infants’ speech production.
This study utilized electroencephalographic recordings to examine whether young children with autism spectrum disorder (ASD) have impaired face recognition ability. High-density brain event-related potentials (ERPs) were recorded to photos of the child’s mother’s face versus an unfamiliar female face and photos of a favorite versus an unfamiliar toy from children with ASD, children with typical development, and children with developmental delay, all 3 to 4 years of age (N = 118). Typically developing children showed ERP amplitude differences in two components, P400 and Nc, to a familiar versus an unfamiliar face, and to a familiar versus an unfamiliar object. In contrast, children with ASD failed to show differences in ERPs to a familiar versus an unfamiliar face, but they did show P400 and Nc amplitude differences to a familiar versus an unfamiliar object. Developmentally delayed children showed significant ERP amplitude differences for the positive slow wave for both faces and objects. These data suggest that autism is associated with face recognition impairment that is manifest early in life.
Although hindsight bias (the “I knew it all along” phenomenon) has been documented in adults, its development has not been investigated. This is despite the fact that hindsight bias errors closely resemble the errors children make on theory of mind (ToM) tasks. Two main goals of the present work were to (a) create a battery of hindsight tasks for preschoolers, and (b) assess the relation between children’s performance on these and ToM tasks. In two experiments involving 144 preschoolers, 3-, 4-, and 5-year olds exhibited strong hindsight bias. Performance on hindsight and ToM tasks was significantly correlated independent of age, language ability, and inhibitory control. These findings contribute to a more comprehensive account of perspective taking across the lifespan.
This study investigated the unique contributions of joint attention, imitation, and toy play to language ability and rate of development of communication skills in young children with autism spectrum disorder (ASD). Sixty preschool-aged children with ASD were assessed using measures of joint attention, imitation, toy play, language, and communication ability. Two skills, initiating protodeclarative joint attention and immediate imitation, were most strongly associated with language ability at age 3–4 years, whereas toy play and deferred imitation were the best predictors of rate of communication development from age 4 to 6.5 years. The implications of these results for understanding the nature and course of language development in autism and for the development of targeted early interventions are discussed.
Autism; Language; Communication; Joint attention; Imitation; Play
Two experiments systematically examined factors that influence infants’ manual search for hidden objects (N = 96). Experiment 1 used a new procedure to assess infants’ search for partially versus totally occluded objects. Results showed that 8.75-month-old infants solved partial occlusions by removing the occluder and uncovering the object, but these same infants failed to use this skill on total occlusions. Experiment 2 used sound-producing objects to provide a perceptual clue to the objects’ hidden location. Sound clues significantly increased the success rate on total occlusions for 10-month-olds, but not for 8.75-month-olds. An identity development account is offered for why infants succeed on partial occlusions earlier than total occlusions and why sound helps only the older infants. We propose a mechanism for how infants use object identity as a basis for developing a notion of permanence. Implications are drawn for understanding the dissociation between looking-time and search assessments of object permanence.
object permanence; identity; manual search; spatial cognition; development; representation
Fourteen-month-old infants saw an object hidden inside a container and were removed from the disappearance locale for 24 hr. Upon their return, they searched correctly for the hidden object, demonstrating object permanence and long-term memory. Control infants who saw no disappearance did not search. In Experiment 2, infants returned to see the container either in the same or a different room. Performance by room-change infants dropped to baseline levels, suggesting that infant search for hidden objects is guided by numerical identity. Infants seek the individual object that disappeared, which exists in its original location, not in a different room. A new behavior, identity-verifying search, was discovered and quantified. Implications are drawn for memory, spatial understanding, object permanence, and object identity.
Infants represent the acts of others and their own acts in commensurate terms. They can recognize cross-modal equivalences between acts they see others perform and their own felt bodily movements. This recognition of self–other equivalences in action gives rise to interpreting others as having similar psychological states such as perceptions and emotions. The ‘like me’ nature of others is the starting point for social cognition, not its culmination.
Young children learn from others’ examples, and they do so selectively. We examine whether the efficacy of prior experiences influences children’s imitation. Thirty-six-month-olds had initial experience on a causal learning task either by performing the task themselves or by watching an adult perform it. The nature of the experience was manipulated such that the actor had either an easy or a difficult experience completing the task. Next, a second adult demonstrated an innovative technique for completing it. Children who had a difficult first-person experience, and those who had witnessed another person having difficulty, were significantly more likely to adopt and imitate the adult’s innovation than those who had or witnessed an easy experience. Children who observed another were also more likely to imitate than were those who had the initial experience themselves. Imitation is influenced by prior experience, both when it is obtained through one’s own hands-on motor manipulation and when it derives from observing the acts of others.
imitation; prior experience; causal learning; goals; social cognition
How do human children come to understand the actions of other people? What neural systems are associated with the processing of others’ actions and how do these systems develop, starting in infancy? These questions span cognitive psychology and developmental cognitive neuroscience, and addressing them has important implications for the study of social cognition. A large amount of research has used behavioral measures to investigate infants’ imitation of the actions of other people; a related but smaller literature has begun to use neurobiological measures to study of infants’ action representation. Here we focus on experiments employing electroencephalographic (EEG) techniques for assessing mu rhythm desynchronization in infancy, and analyze how this work illuminates the links between action perception and production prior to the onset of language.
Upon learning the outcome to a problem, people tend to believe that they knew it all along (hindsight bias). Here we report the first study to trace the development of hindsight bias across the lifespan. 194 participants aged 3 to 95 years completed three tasks designed to measure visual and verbal hindsight bias. All age groups demonstrated hindsight bias on all three tasks; however, preschoolers and the elderly exhibited more bias than older children and younger adults. Multinomial processing tree analyses of these data revealed that preschoolers’ enhanced hindsight bias resulted from them substituting the correct answer for their original answer in their recall (a qualitative error). Conversely, older adults’ enhanced hindsight bias resulted from them forgetting their original answer and recalling an answer closer to, but not equal to, the correct answer (a quantitative error). We discuss these findings in relation to mechanisms of memory, perspective-taking, theory of mind, and executive function.
Hindsight bias; lifespan cognitive development; mathematical models of cognition; executive function; perspective taking
Adults’ causal representations integrate information about predictive relations and the possibility of effective intervention; if one event reliably predicts another, adults can represent the possibility that acting to bring about the first event might generate the second. Here we show that although toddlers (mean age: 24 months) readily learn predictive relationships between physically connected events, they do not spontaneously initiate one event to try to generate the second (although older children, mean age: 47 months, do; Experiments 1 and 2). Toddlers succeed only when the events are initiated by a dispositional agent (Experiment 3), when the events involve direct contact between objects (Experiment 4), or when the events are described using causal language (Experiment 5). This suggests that causal language may help children extend their initial causal representations beyond agent-initiated and direct contact events.
Causal reasoning; Cognitive development; Agency; Contact relations; Language
Two experiments were used to investigate the scope of imitation by testing whether 36-month-olds can learn to produce a categorization strategy through observation. After witnessing an adult sort a set of objects by a visible property (their color; Experiment 1) or a nonvisible property (the particular sounds produced when the objects were shaken; Experiment 2), children showed significantly more sorting by those dimensions relative to children in control groups, including a control in which children saw the sorted endstate but not the intentional sorting demonstration. The results show that 36-month-olds can do more than imitate the literal behaviors they see; they also abstract and imitate rules that they see another person use.
imitation; rules; abstract reasoning; social learning; children
There is increasing interest in neurobiological methods for investigating the shared representation of action perception and production in early development. We explored the extent and regional specificity of EEG desynchronization in the infant alpha frequency range (6–9 Hz) during action observation and execution in 14-month-old infants. Desynchronization during execution was restricted to central electrode sites, while action observation was associated with a broader desynchronization across frontal, central, and parietal regions. The finding of regional specificity in the overlap between EEG responses to action execution and observation suggests that the rhythm seen in the 6–9 Hz range over central sites in infancy shares certain properties with the adult mu rhythm. The magnitude of EEG desynchronization to action perception and production appears to be smaller for infants than for adults and older children, suggesting developmental change in this measure.