Deferred imitation and object permanence (OP) were tested in 48 young children with Down syndrome (DS), ranging from 20 to 43 months of age. Deferred imitation and high-level OP (invisible displacements) have long been held to be synchronous developments during sensory-motor “Stage 6” (18–24 months of age in unimpaired children). The results of the current study demonstrate deferred imitation in young children with DS, showing they can learn novel behaviors from observation and retain multiple models in memory. This is the first demonstration of deferred imitation in young children with DS. The average OP level passed in this sample was A-not-B, a task passed at 8–12 months of age in normally developing infants. Analyses showed that individual children who failed high-level OP (invisible displacements) could still perform deferred imitation. This indicates that deferred imitation and OP invisible displacements are not synchronous developments in children with DS. This asynchrony is compatible with new data from unimpaired children suggesting that deferred imitation and high-level OP entail separate and distinctive kinds of memory and representation.
Manual search for totally occluded objects was investigated in 10-, 12- and 14-month-old infants. Infants responded to two types of total hiding in different ways, supporting the inference that object permanence is not a once-and-for-all attainment. Occlusion of an object by movement of a screen over it was solved at an earlier age than occlusion in which an object was carried under the screen. This dissociation was not explained by motivation, motor skill or means–ends coordination, because for both tasks the same object was hidden in the same place under the same screen and required the same uncovering response. This dissociation generalized across an experimentally manipulated change in recovery means—infants removed cloths while seated at a table in Expt 1 and were required to crawl through 3-D space to displace semi-rigid pillows in Expt 2. Further analysis revealed that emotional response varied as a function of hiding, suggesting an affective correlate of infant cognition. There are four empirical findings to account for: developmental change, task dissociation, generalization of the effects across recovery means, and emotional reactions. An identity-development theory is proposed explaining these findings in terms of infants’ understanding of object identity and the developmental relationship between object identity and object permanence. Object identity is seen as a necessary precursor to the development of object permanence.
We used imitation as a tool for investigating how young children code action. The study was designed to examine the errors children make in re-enacting manual gestures they see. Thirty-two 3-year-old children served as subjects. Each child was shown 24 gestures, generated by systematically crossing four factors: visual monitoring, spatial endpoint, movement path, and number of hands. The results showed no difference as a function of whether the children could visually monitor their own responses. Interestingly, children made significantly more errors when the adult’s action terminated on a body part than they did when the same movement terminated near the body part. There were also significantly more errors when the demonstrated act involved crossing midline than when it did not, and more errors when it involved one hand rather than two hands. Our hypothesis is that human acts are coded in terms of goals. The goals are hierarchically organized, and because young children have difficulty simultaneously integrating multiple goals into one act they often re-enact the goals that are ranked higher, which leads to the errors observed. We argue that imitation is an active reconstruction of perceived events and taps cognitive processing. We suggest that the goal-based imitation in 3-year-olds is a natural developmental outgrowth of the perceptual–motor mapping and goal-directed coding of human acts found in infancy.
The influence of changes in context and object characteristics on deferred imitation was assessed in 14-month-old infants. In Experiment 1, infants in the imitation group saw an adult demonstrate target acts on miniature objects in an unusual context (an orange polka-dot tent). When later presented with larger objects in a normal laboratory room, these infants performed significantly more target acts than did controls. In Experiment 2, three groups of infants were tested. Infants in an imitation(no change) group saw an adult demonstrate target acts and were subsequently tested in the same room using the same objects as the adult. Infants in the imitation (context + object size & color change) group followed the same procedure, but both the context and two salient featural characteristics of the objects (size and color) were changed between encoding and the recall test of deferred imitation. Control infants did not see the target demonstrations. Results showed that the combined changes in context and object features led to a significant decrease in imitative performance. Nonetheless, in comparison to the controls, infants exhibited significant recall as indexed by deferred imitation. The results show that imitation generalizes across changes in object size, object color, and test context. The implications for theories of memory and representational development are discussed.
infants; imitation; recall; memory; context; shape; generalization; stimulus similarity; amnesia; play
Facial imitation was investigated in infants 6 weeks and 2 to 3 months of age. Three findings emerged: (a) early imitation did not vary as a function of familiarity with the model—infants imitated a stranger as well as their own mothers; (b) infants imitated both static facial postures and dynamic facial gestures; and (c) there was no disappearance of facial imitation in the 2- to 3-month age range, contrary to previous reports. Two broad theoretical points are developed. First, a proposal is made about the social and psychological functions that early imitation serves in infants’ encounters with people. It is argued that infants deploy imitation to enrich their understanding of persons and actions and that early imitation is used for communicative purposes. Second, a theoretical bridge is formed between early imitation and the “object concept.” The bridge is formed by considering the fundamental role that identity plays in infants’ understanding of people and things. One of the psychological functions that early imitation subserves is to identify people. Infants use the nonverbal behavior of people as an identifier of who they are and use imitation as a means of verifying this identity. Data and theory are adduced in favor of viewing early imitation as an act of social cognition.
imitation; faces; cross-modal; memory; mental representation; categorization; object identity; mother–infant interaction; theory of mind
Imitation was tested both immediately and after a 24-hr retention interval in 6-week-old infants. The results showed immediate imitation, which replicates past research, and also imitation from memory, which is new. The latter finding implicates recall memory and establishes that 6-week-olds can generate actions on the basis of stored representations. The motor organization involved in imitation was investigated through a microanalysis of the matching response. Results revealed that infants gradually modified their behavior towards more accurate matches over successive trials. It is proposed that early imitation serves a social identity function. Infants are motivated to imitate after a 24-hr delay as a means of clarifying whether the person they see before them is the same one they previously encountered. They use the reenactment of a person’s behavior to probe whether this is the same person. In the domain of inanimate objects, infants use physical manipulations (e.g., shaking) to perform this function. Imitation is to understanding people as physical manipulation is to understanding things. Motor imitation, the behavioral reenactment of things people do, is a primitive means of understanding and communicating with people.
imitation; memory; mental representation; faces; cross-modal; motor coordination; self; identity; communication; theory of mind; development
The sensorimotor theory of infancy has been overthrown, but there is little consensus on a replacement. We hypothesize that a capacity for representation is the starting point for infant development, not its culmination. Logical distinctions are drawn between object representation, identity, and permanence. Modern experiments on early object permanence and deferred imitation suggest: (a) even for young infants, representations persist over breaks in sensory contact, (b) numerical identity of objects (Os) is initially specified by spatiotemporal criteria (place and trajectory), (c) featural and functional identity criteria develop, (d) events are analyzed by comparing representations to current perception, and (e) representation operates both prospectively, anticipating future contacts with an O, and retrospectively, reidentifying an O as the “same one again.” A model of the architecture and functioning of the early representational system is proposed. It accounts for young infants’ behavior toward absent people and things in terms of their efforts to determine the identity of objects. Our proposal is developmental without denying innate structure and elevates the power of perception and representation while being cautious about attributing complex concepts to young infants.
representation; object identity; object permanence; imitation; cognitive development; memory
Investigated was whether children would re-enact what an adult actually did or what the adult intended to do. In Experiment 1 children were shown an adult who tried, but failed, to perform certain target acts. Completed target acts were thus not observed. Children in comparison groups either saw the full target act or appropriate controls. Results showed that children could infer the adult’s intended act by watching the failed attempts. Experiment 2 tested children’s understanding of an inanimate object that traced the same movements as the person had followed. Children showed a completely different reaction to the mechanical device than to the person: They did not produce the target acts in this case. Eighteen-month-olds situate people within a psychological framework that differentiates between the surface behavior of people and a deeper level involving goals and intentions. They have already adopted a fundamental aspect of folk psychology—persons (but not inanimate objects) are understood within a framework involving goals and intentions.
This study evaluated the psychological mechanisms underlying imitation of facial actions in young infants. A novel aspect of the study was that it used a nonoral gesture that had not been tested before (head movement), as well as a tongue-protrusion gesture. Results showed imitation of both displays. Imitation was not limited to the intervals during which the experimenter’s movements were displayed; Ss also imitated from memory after the display had stopped. The results established that newborn imitation is not constrained to a few privileged oral movements. The findings support Meltzoff and Moore’s hypothesis that early imitation is mediated by an active cross-modal matching process. A common representational code may unite the perception and production of basic human acts.
Deferred imitation after a 1-week delay was examined in 14-month-old infants. Six actions, each using a different object, were demonstrated to each infant. One of the six actions was a novel behavior that had a zero probability of occurrence in spontaneous play. In the imitation condition, infants observed the demonstration but were not allowed to touch the objects, thus preventing any immediate imitation. After the 1-week delay, infants returned to the laboratory and their imitation of the adult’s previous actions was scored. Infants in the imitation condition produced significantly more of the target actions than infants in control groups who were not exposed to the modeling; there was also strong evidence for the imitation of the novel act. From a cognitive perspective deferred imitation provides a means of assessing recall memory and representation in children. From a social-developmental viewpoint the findings illustrate that the behavioral repertoire of infants and their knowledge about objects can expand as a result of seeing the actions of others.
Long-term recall memory, as indexed by deferred imitation, was assessed in 12-month-old infants. Independent groups of infants were tested after retention intervals of 3 min, 1 week and 4 weeks. Deferred imitation was assessed using the ‘observation-only’ procedure in which infants were not allowed motor practice on the tasks before the delay was imposed. Thus, the memory could not have been based on re-accessing a motor habit, because none was formed in the first place. After the delay, memory was assessed either in the same or a different environmental context from the one in which the adult had originally demonstrated the acts. In Experiments 1 and 3, infants observed the target acts while in an unusual environment (an orange and white polka-dot tent), and recall memory was tested in an ordinary room. In Experiment 2, infants observed the target acts in their homes and were tested for memory in a university room. The results showed recall memory after all retention intervals, including the 4 week delay, with no effect of context change. Interestingly, the forgetting function showed that the bulk of the forgetting occurred during the first week. The findings of recall memory without motor practice support the view that infants as young as 12 months old use a declarative (nonprocedural) memory system to span delay intervals as long as 4 weeks.
Recent work has suggested the value of electroencephalographic (EEG) measures in the study of infants’ processing of human action. Studies in this area have investigated desynchronization of the sensorimotor mu rhythm during action execution and action observation in infancy. Untested but critical to theory is whether the mu rhythm shows a differential response to actions which share similar goals but have different motor requirements or sensory outcomes. By varying the invisible property of object weight, we controlled for the abstract goal (reach, grasp, and lift the object), while allowing other aspects of the action to vary. The mu response during 14-month-old infants’ own executed actions showed a differential hemispheric response between acting on heavier and lighter objects. EEG responses also showed sensitivity to “expected object weight” when infants simply observed an experimenter reach for objects that the infants’ prior experience indicated were heavier versus lighter. Crucially, this neural reactivity was predictive – during the observation of the other reaching toward the object, before lifting occurred. This suggests that infants’ own self-experience with a particular object’s weight influences their processing of others’ actions on the object, with implications for developmental social-cognitive neuroscience.
EEG; mu rhythm; action; infant; goals; neural mirroring
This study investigated deferred imitation using a longitudinal design. A total of 62 Swedish children (32 girls) were tested at both 9 and 14 months of age. The memory delay interval was 10 minutes at 9 months and five minutes at 14 months of age. At both ages children in the imitation group displayed significantly more target actions after modelling than the children in the control group, thus replicating earlier reports of imitation from memory. It was found that individual children with a tendency to perform low deferred imitation at 9 months of age tended to remain low on the test at 14 months, thus raising the possibility of stable individual differences in imitation. This study provides a first investigation of deferred imitation longitudinally among young children, and supports recent theoretical claims that deferred imitation arises earlier in ontogeny than was hypothesized by classical theory. It was observed that there are cultural differences in the way that Swedish versus American adult–infant pairs act in the test situation and ideas are offered regarding the roots of such differences.
Three experiments examined peer imitation with 14- to 18-month-old infants. In Experiment 1, infants saw a trained 14-month-old (“expert peer”) perform specific actions on 5 objects. Imitation from memory was tested after a 5-min delay. In Experiment 2, the infants observed an expert peer in the laboratory, and retention and imitation were tested in the home (change of context) after a 2-day delay. In Experiment 3, a peer demonstrated target acts at a day care, and after a 2-day delay infants were tested in their homes. Results from all 3 experiments showed significant imitation compared with controls. The experiments demonstrate social learning from peers during infancy and also provide the first evidence for infant imitation from memory across a change in context.
Both the medial temporal lobe and dorsolateral prefrontal cortex have been implicated in autism. In the present study, performance on two neuropsychological tasks—one tapping the medial temporal lobe and related limbic structures, and another tapping the dorsolateral prefrontal cortex—was examined in relation to performance on tasks assessing autistic symptoms in young children with autism, and developmentally matched groups of children with Down syndrome or typical development. Autistic symptoms included orienting to social stimuli, immediate and deferred motor imitation, shared attention, responses to emotional stimuli, and symbolic play. Compared with children with Down syndrome and typically developing children, children with autism performed significantly worse on both the medial temporal lobe and dorsolateral prefrontal tasks, and on tasks assessing symptoms domains. For children with autism, the severity of autistic symptoms was strongly and consistently correlated with performance on the medial temporal lobe task, but not the dorsolateral prefrontal task. The hypothesis that autism is related to dysfunction of the medial temporal lobe and related limbic structures, such as the orbital prefrontal cortex, is discussed.
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
The shift from childhood to adolescence is characterized by rapid remodeling of the brain and increased risk-taking behaviors. Current theories hypothesize that developmental enhancements in sensitivity to affective environmental cues in adolescence may undermine executive function (EF) and increase the likelihood of problematic behaviors. In the current study, we examined the extent to which EF in childhood predicts EF in early adolescence. We also tested whether individual differences in neural responses to affective cues (rewards/punishments) in childhood serve as a biological marker for EF, sensation-seeking, academic performance, and social skills in early adolescence. At age 8, 84 children completed a gambling task while event-related potentials (ERPs) were recorded. We examined the extent to which selections resulting in rewards or losses in this task elicited (i) the P300, a post-stimulus waveform reflecting the allocation of attentional resources toward a stimulus, and (ii) the SPN, a pre-stimulus anticipatory waveform reflecting a neural representation of a “hunch” about an outcome that originates in insula and ventromedial PFC. Children also completed a Dimensional Change Card-Sort (DCCS) and Flanker task to measure EF. At age 12, 78 children repeated the DCCS and Flanker and completed a battery of questionnaires. Flanker and DCCS accuracy at age 8 predicted Flanker and DCCS performance at age 12, respectively. Individual differences in the magnitude of P300 (to losses vs. rewards) and SPN (preceding outcomes with a high probability of punishment) at age 8 predicted self-reported sensation seeking (lower) and teacher-rated academic performance (higher) at age 12. We suggest there is stability in EF from age 8 to 12, and that childhood neural sensitivity to reward and punishment predicts individual differences in sensation seeking and adaptive behaviors in children entering adolescence.
executive function; affective decision-making; event-related potentials; adolescence; reward processing
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
A long-standing puzzle in developmental psychology is how infants imitate gestures they cannot see themselves perform (facial gestures). Two critical issues are: (a) the metric infants use to detect cross-modal equivalences in human acts and (b) the process by which they correct their imitative errors. We address these issues in a detailed model of the mechanisms underlying facial imitation. The model can be extended to encompass other types of imitation. The model capitalizes on three new theoretical concepts. First, organ identification is the means by which infants relate parts of their own bodies to corresponding ones of the adult’s. Second, body babbling (infants’ movement practice gained through self-generated activity) provides experience mapping movements to the resulting body configurations. Third, organ relations provide the metric by which infant and adult acts are perceived in commensurate terms. In imitating, infants attempt to match the organ relations they see exhibited by the adults with those they feel themselves make. We show how development restructures the meaning and function of early imitation. We argue that important aspects of later social cognition are rooted in the initial cross-modal equivalence between self and other found in newborns.
imitation; faces; cross-modal; memory; motor coordination; self
A leading question in developmental social-cognitive neuroscience concerns the nature and function of neural links between action perception and production in early human development. Here we document a somatotopic pattern of activity of the sensorimotor EEG mu rhythm in 14-month-old infants. EEG was recorded during interactive trials in which infants activated a novel object using their own hands or feet (“execution” trials) and watched an experimenter use her hands or feet to achieve the same goal (“observation” trials). At central electrodes overlying sensorimotor hand areas (C3/C4), mu rhythm power was reduced (indicating greater cortical activation) during infants' execution of hand acts compared to foot acts. For the central electrode overlying the sensorimotor foot area (Cz), mu power was reduced during the execution of foot versus hand acts. Strikingly similar somatotopic patterns were found in both the action execution and observation conditions. We hypothesize that these somatotopic patterns index an intercorporeal mapping of corresponding body parts between self and other. We further propose that infants' ability to identify self-other equivalences at the level of body parts underlies infant imitation and is an ontogenetic building block for the feelings of intersubjectivity we experience when socially engaged with other people.
Infant; brain; EEG; imitation; neural mirroring; mu rhythm; social cognition; intersubjectivity
Infants have difficulty transferring information between 2D and 3D sources. The current study extends Zack et al.’s (2009) touch screen imitation task to examine whether the addition of specific language cues significantly facilitates 15-month-olds’ transfer of learning between touch screens and real-world 3D objects. The addition of two kinds of linguistic cues (object label plus verb or nonsense name) did not elevate action imitation significantly above levels observed when such language cues were not used. Language cues hindered infants’ performance in the 3D→2D direction of transfer, but only for the object label plus verb condition. The lack of a facilitative effect of language is discussed in terms of competing cognitive loads imposed by conjointly transferring information across dimensions and processing linguistic cues in an action imitation task at this age.