Origins of the human pointing gesture: a training study

Despite its importance in the development of children’s skills of social cognition and communication, very little is known about the ontogenetic origins of the pointing gesture. We report a training study in which mothers gave children one month of extra daily experience with pointing as compared with a control group who had extra experience with musical activities. One hundred and two infants of 9, 10, or 11 months of age were seen at the beginning, middle, and end of this one‐month period and tested for declarative pointing and gaze following. Infants’ability to point with the index finger at the end of the study was not affected by the training but was instead predicted by infants’ prior ability to follow the gaze direction of an adult. The frequency with which infants pointed indexically was also affected by infant gaze following ability and, in addition, by maternal pointing frequency in free play, but not by training. In contrast, infants’ ability to monitor their partner’s gaze when pointing, and the frequency with which they did so, was affected by both training and maternal pointing frequency in free play. These results suggest that prior social cognitive advances, rather than adult socialization of pointing per se, determine the developmental onset of indexical pointing, but socialization processes such as imitation and adult shaping subsequently affect both infants’ ability to monitor their interlocutor’s gaze while they point and how frequently infants choose to point.     

Development of category formation for faces differing by age in 9‐ to 12‐month‐olds: An effect of experience with infant faces

We examined category formation for faces differing in age in 9‐ and 12‐month‐olds, and the influence of exposure to infant faces on such ability. Infants were familiarized with adult or infant faces, and then tested with a novel exemplar from the familiarized category paired with a novel exemplar from a novel category (Experiment 1). Both age groups formed discrete categories of adult and infant faces, but exposure to infant faces in everyday life did not modulate performance. The same task was conducted with child versus infant faces (Experiment 2). Whereas 9‐month‐olds preferred infant faces after familiarization with child faces, but not child faces after familiarization with infant faces, 12‐month‐olds formed discrete categories of child and infant faces. Moreover, more exposure to infant faces correlated with higher novel category preference scores when infants were familiarized with infant faces in 12‐month‐olds, but not 9‐month‐olds. The 9‐month‐old asymmetry did not reflect spontaneous preference for infant over child faces (Experiment 3). These findings indicate that 9‐ and 12‐month‐olds can form age‐based categories of faces. The ability of 12‐month‐olds to form separate child and infant categories suggests that they have a more exclusive representation of face age, one that may be influenced by prior experience with infant faces.     

Perceptual narrowing towards adult faces is a cross‐cultural phenomenon in infancy: a behavioral and near‐infrared spectroscopy study with Japanese infants

Recent data showed that, in Caucasian infants, perceptual narrowing occurs for own‐race adult faces between 3 and 9 months of age, possibly as a consequence of the extensive amount of social and perceptual experience accumulated with caregivers and/or other adult individuals of the same race of the caregiver. The neural correlates of this developmental process remain unexplored, and it is currently unknown whether perceptual tuning towards adult faces can be extended to other cultures. To this end, in the current study we tested the ability of 3‐ and 9‐month‐old Japanese infants to discriminate among adult and infant Asian faces in a visual familiarization task (Experiment 1), and compared 9‐month‐olds’ cerebral hemodynamic responses to adult and infant faces as measured by near‐infrared spectroscopy (NIRS) (Experiment 2). Results showed that 3‐month‐olds exhibit above‐chance discrimination of adult and infant faces, whereas 9‐month‐olds discriminate adult faces but not infant faces (Experiment 1). Moreover, adult faces, but not infant faces, induced significant increases in hemodynamic responses in the right temporal areas of 9‐month‐old infants. Overall, our data suggest that perceptual narrowing towards adult faces is a cross‐cultural phenomenon occurring between 3 and 9 months of age, and translates by 9 months of age into a right‐hemispheric specialization in the processing of adult faces.     

A parent intervention with a growth mindset approach improves children's early gesture and vocabulary development

Socioeconomic disparities in children's early vocabulary skills can be traced back to disparities in gesture use at age one and are due, in part, to the quantity and quality of communication children are exposed to by parents. Further, parents' mindsets about intelligence contribute to their interactions with their children. We implemented a parent gesture intervention with a growth mindset component with 47 parents of 10‐month‐olds to determine whether this approach would increase parents' use of the pointing gesture, infants' use of pointing, and child vocabulary growth. The intervention had an effect on parent gesture such that by child age 12‐months, parents who received the intervention increased in their pointing more than parents in the control condition. Importantly, the intervention also had a significant effect on child gesture use with parents. There was no main effect of the intervention on child vocabulary. Further, the effect of the intervention on pointing was stronger for parents who endorsed fixed mindsets at baseline, and had an added benefit of increased vocabulary growth from 10–18 months for children of those parents who endorsed fixed mindsets. Incorporating growth mindset approaches into parenting interventions is encouraged.     

Learning from others in 9‐18‐month‐old infants

The use of an adult as a resource for help and instruction in a problem solving situation was examined in 9, 14, and 18‐month‐old infants. Infants were placed in various situations ranging from a simple means‐end task where a toy was placed beyond infants' prehensile space on a mat, to instances where an attractive toy was placed inside closed transparent boxes that were more or less difficult for the child to open. The experimenter gave hints and modelled the solution each time the infant made a request (pointing, reaching, or showing a box to the experimenter), or if the infant was unable to solve the problem. Infants' success on the problems, sensitivity to the experimenter's modelling, and communicative gestures (requests, co‐occurrence of looking behaviour and requests) were analysed. Results show that older infants had better success in solving problems although they exhibited difficulties in solving the simple means‐end task compared to the younger infants. Moreover, 14‐ and 18‐month‐olds were sensitive to the experimenter's modelling and used her demonstration cues to solve problems. By contrast, 9‐month‐olds did not show such sensitivity. Finally, 9‐month‐old infants displayed significantly fewer communicative gestures toward the adult compared to the other age groups, although in general, all infants tended to increase their frequency of requests as a function of problem difficulty. These observations support the idea that during the first half of the second year infants develop a new collaborative stance toward others. The stance is interpreted as foundational to teaching and instruction, two mechanisms of social learning that are sometime considered as specifically human. Copyright © 2006 John Wiley & Sons, Ltd.     

Nine-month-olds’ shared visual attention as a function of gesture and object location

Two factors hypothesized to affect shared visual attention in 9-month-olds were investigated in two experiments. In Experiment 1, we examined the effects of different attention-directing actions (looking, looking and pointing, and looking, pointing and verbalizing) on 9-month-olds’ engagement in shared visual attention. In Experiment 1 we also varied target object locations (i.e., in front, behind, or peripheral to the infant) to test whether 9-month-olds can follow an adult’s gesture past a nearby object to a more distal target. Infants followed more elaborate parental gestures to targets within their visual field. They also ignored nearby objects to follow adults’ attention to a peripheral target, but not to targets behind them. In Experiment 2, we rotated the parent 90° from the infant’s midline to equate the size of the parents’ head turns to targets within as well as outside the infants’ visual field. This manipulation significantly increased infants’ looking to target objects behind them, however, the frequency of such looks did not exceed chance. The results of these two experiments are consistent with perceptual and social experience accounts of shared visual attention.     

Joint attention and object learning in 5‐ and 7‐month‐old infants

We examined the effects of joint attention for object learning in 5‐ and 7‐month‐old infants. Infants interacted with an adult social partner who taught them about a novel toy in two conditions. In the Joint Attention condition, the adult spoke about the toy while alternating gaze between the infant and the toy, while in the Object Only condition, the adult looked to the toy and to a spot on the ceiling, but never at the infant. In the test trials following each social interaction, we presented infants with the ‘familiarization’ toy and a novel toy, and monitored looking times to each object. We found that 7‐month‐olds looked significantly longer to the novel toy following the Joint Attention relative to the Object Only condition, while 5‐month‐old infants did not show a significant difference across conditions. We interpret these results to suggest that joint attention facilitated 7‐month‐old infants' encoding of information about the familiarization object. Implications for the ontogeny of infant learning in joint attention contexts are discussed. Copyright © 2007 John Wiley & Sons, Ltd.     

Precursors of a theory of mind: A longitudinal study

The study examined whether the pointing gesture and intentional understanding abilities at 12 and 15 months of age predict the later understanding of perception and intention, as well as the ability to explain others' actions in a psychological way at 39 months of age. Thirty‐five infants (18 girls) were administered pointing and intention‐understanding tasks at the age of 12 and 15 months. Children were again evaluated at the age of 39 months with perception and intention tasks, and a psychological explanation task. Results showed that only 12‐month‐olds' comprehension of the pointing gesture with an imperative motive contributed to the prediction of later understanding of perception and mentalistic explanations of actions. Moreover, the ability of 12‐ and 15‐month‐olds to understand intentions contributed to the prediction of later preschool understanding of perceptions and intentions. These results indicate that a developmental trajectory in children's understanding of mental states from infancy to childhood is present, but depends on the level of engagement and communication that are required to perform these tasks.     

Give Me a Hand: Adult Involvement During Object Exploration Affects Object Individuation in Infancy

The development of object individuation, a fundamental ability that supports identification and discrimination of objects across discrete encounters, has been examined extensively by researchers. There are significant advancements in infants' ability to individuate objects during the first year‐and‐a‐half. Experimental work has established a timeline of object individuation abilities and revealed some mechanisms underlying this ability. However, the influence of adult assistance during object exploration has not yet been explored. The current study investigates the effect of adult involvement during object exploration on infants' object individuation abilities. In Experiment 1a and 1b, we examined 9.5‐month‐old infants' colour‐based object individuation following adult‐assisted multisensory object exploration. Two components of adult interaction were of particular interest: facilitation of object manipulation (grasping, rotating, and attention‐getting behaviours) and social engagement (smiling, pointing, attention‐getting verbalizations, and object‐directed gaze). Experiment 2a and 2b assessed these components with 4.5‐month‐olds to examine their impact across development. The results showed that after adult‐guided object exploration, both 9.5‐ and 4.5‐month‐old infants successfully individuated previously undifferentiated objects. Results of Experiments 1b and 2b provide implications for the mechanisms underlying the scaffolding influence of adult interaction during infant behaviours. Copyright © 2015 John Wiley & Sons, Ltd.     

Children's use of gesture to resolve lexical ambiguity

We report on a study investigating 3–5‐year‐old children's use of gesture to resolve lexical ambiguity. Children were told three short stories that contained two homonym senses; for example, bat (flying mammal) and bat (sports equipment). They were then asked to re‐tell these stories to a second experimenter. The data were coded for the means that children used during attempts at disambiguation: speech, gesture, or a combination of the two. The results indicated that the 3‐year‐old children rarely disambiguated the two senses, mainly using deictic pointing gestures during attempts at disambiguation. In contrast, the 4‐year‐old children attempted to disambiguate the two senses more often, using a larger proportion of iconic gestures than the other children. The 5‐year‐old children used less iconic gestures than the 4‐year‐olds, but unlike the 3‐year‐olds, were able to disambiguate the senses through the verbal channel. The results highlight the value of gesture to the development of children's language and communication skills.     

Infant gaze following depends on communicative signals: An eye‐tracking study of 5‐ to 7‐month‐olds in Vanuatu

Gaze is considered a crucial component of early communication between an infant and her caregiver. When communicatively addressed, infants respond aptly to others’ gaze by following its direction. However, experience with face‐to‐face contact varies across cultures, begging the question whether infants’ competencies in receiving others’ communicative gaze signals are universal or culturally specific . We used eye‐tracking to assess gaze‐following responses of 5‐ to 7‐month olds in Vanuatu, where face‐to‐face parent–infant interactions are less prevalent than in Western populations. We found that—just like Western 6‐month‐olds studied previously—5‐ to ‐7‐month‐olds living in Vanuatu followed gaze only, when communicatively addressed. That is, if presented gaze shifts were preceded by infant‐directed speech, but not if they were preceded by adult‐directed speech. These results are consistent with the notion that early infant gaze following is tied to infants’ early emerging communicative competencies and rooted in universal mechanisms rather than being dependent on cultural specificities of early socialization.     

Two‐year‐olds use adults' but not peers' points

In the current study, 24‐ to 27‐month‐old children (N = 37) used pointing gestures in a cooperative object choice task with either peer or adult partners. When indicating the location of a hidden toy, children pointed equally accurately for adult and peer partners but more often for adult partners. When choosing from one of three hiding places, children used adults’ pointing to find a hidden toy significantly more often than they used peers’. In interaction with peers, children's choice behavior was at chance level. These results suggest that toddlers ascribe informative value to adults’ but not peers’ pointing gestures, and highlight the role of children's social expectations in their communicative development.     

The Development of the Ability to Semantically Integrate Information in Speech and Iconic Gesture in Comprehension

We examined whether children's ability to integrate speech and gesture follows the pattern of a broader developmental shift between 3‐ and 5‐year‐old children (Ramscar & Gitcho, 2007) regarding the ability to process two pieces of information simultaneously. In Experiment 1, 3‐year‐olds, 5‐year‐olds, and adults were presented with either an iconic gesture or a spoken sentence or a combination of the two on a computer screen, and they were instructed to select a photograph that best matched the message. The 3‐year‐olds did not integrate information in speech and gesture, but 5‐year‐olds and adults did. In Experiment 2, 3‐year‐old children were presented with the same speech and gesture as in Experiment 1 that were produced live by an experimenter. When presented live, 3‐year‐olds could integrate speech and gesture. We concluded that development of the integration ability is a part of the broader developmental shift; however, live‐presentation facilitates the nascent integration ability in 3‐year‐olds.     

Definitions of bullying: Age differences in understanding of the term,and the role of experience

We report two studies that examine age differences in pupils' and parents' definitions of the term bullying, and possible reasons for these including the role of specific experiences. Study 1 compared definitions of bullying given by participants in four age groups; 4 to 6 years, 8 years, 14 years and adult. Participants were shown/read 17 different cartoon scenarios and were asked if each constituted an episode of bullying or not. Multidimensional scaling indicated that the groups differed in their definition of bullying. 4‐ to 6‐year‐olds and 8‐year‐olds used 1 dimension, a distinction between aggressive and non‐aggressive acts, when differentiating cartoons; 14‐year‐olds and adults gave a 2‐dimensional solution, also distinguishing between physical and non‐physical (social/relational or verbal) acts. Study 2 further investigated definitions of bullying given by 99 children aged 4 to 6 years, and the role of experience. Just over half had some understanding of the term, but tended to be less concerned about power differences and repetition of actions. No significant differences in definitions were found between boys and girls, or between children in involved (aggressor, victim or defender) or not involved (bystander) roles; however, aggressors were more likely than other children to say that 11 of the 13 aggressive behaviours were not bullying. These findings are discussed in relation to age related changes in experiences of bullying and cognitive development. Implications for interventions and research are also raised.     

Do Questions Get Infants Talking? Infant Vocal Responses to Questions and Declaratives in Maternal Speech

Maternal questions play a crucial role in early language acquisition by virtue of their special grammatical, prosodic and lexical forms, and their abundance in the input. Infants are able to discriminate questions from other sentence types and produce rising intonations in their own requests. This study examined whether caregiver questions were related to the quantity of infant vocalizations. Thirty‐six infants aged 10 and 14 months participated in a laboratory play session with their mothers. In separate blocks, mothers were instructed to ask questions and to refrain from asking questions. Both block‐level and utterance‐level analyses found no evidence that maternal questions affected the amount of infant‐response vocalizations. Mothers of 14‐month‐olds (but not 10‐month‐olds) tended to repeat questions. Copyright © 2016 John Wiley & Sons, Ltd.     

Does ‘Wanting the Best’ create more stress? The link between baby sign classes and maternal anxiety

This study investigated whether gesturing classes (baby sign) affected parental frustration and stress, as advertised by many commercial products. The participants were 178 mother–infant dyads, divided into a gesture group (n=89) and a non‐gesture group (n=89), based on whether they had attended baby sign classes or not. Mothers completed a background demographics questionnaire and the Parenting Stress Index. Gesturing mothers had higher total stress scores, with higher scores on the child domain, despite having similar backgrounds to non‐gesturing mothers. There was no relationship between the frequency or duration of gesture use and stress scores. It is suggested that gesturing mothers had higher pre‐existing stress and were attracted to gesture classes because of the promoted benefits, which include stress reduction, although class attendance did not alleviate their stress. The possibility that attending gesturing classes made mothers view their infant in a more negative way, due to their heightened expectations not being met, is also discussed. Copyright © 2010 John Wiley & Sons, Ltd.     

Do domestic dogs interpret pointing as a command?

Domestic dogs comprehend human gestural communication flexibly, particularly the pointing gesture. Here, we examine whether dogs interpret pointing informatively, that is, as simply providing information, or rather as a command, for example, ordering them to move to a particular location. In the first study a human pointed toward an empty cup. In one manipulation, the dog either knew or did not know that the designated cup was empty (and that the other cup actually contained the food). In another manipulation, the human (as authority) either did or did not remain in the room after pointing. Dogs ignored the human’s gesture if they had better information, irrespective of the authority’s presence. In the second study, we varied the level of authority of the person pointing. Sometimes this person was an adult, and sometimes a young child. Dogs followed children’s pointing just as frequently as they followed adults’ pointing (and ignored the dishonest pointing of both), suggesting that the level of authority did not affect their behavior. Taken together these studies suggest that dogs do not see pointing as an imperative command ordering them to a particular location. It is still not totally clear, however, if they interpret it as informative or in some other way.     

Accommodating variability in voice and foreign accent: flexibility of early word representations

In six experiments with English‐learning infants, we examined the effects of variability in voice and foreign accent on word recognition. We found that 9‐month‐old infants successfully recognized words when two native English talkers with dissimilar voices produced test and familiarization items ( Experiment 1 ). When the domain of variability was shifted to include variability in voice as well as in accent, 13‐, but not 9‐month‐olds, recognized a word produced across talkers when only one had a Spanish accent ( Experiments 2 and 3 ). Nine‐month‐olds accommodated some variability in accent by recognizing words when the same Spanish‐accented talker produced familiarization and test items ( Experiment 4 ). However, 13‐, but not 9‐month‐olds, could do so when test and familiarization items were produced by two distinct Spanish‐accented talkers ( Experiments 5 and 6 ). These findings suggest that, although monolingual 9‐month‐olds have abstract phonological representations, these representations may not be flexible enough to accommodate the modifications found in foreign‐accented speech.     

To generalize or not to generalize: spatial categories are influenced by physical attributes and language

The current work explored the conditions under which infants generalize spatial relationships from one event to another. English‐learning 5‐month‐olds habituated to a tight‐ or loose‐fit covering event dishabituated to a change in fit during a containment test event, but infants habituated to a visually similar occlusion event did not. Thus, infants’ responses appeared to be driven by the physical nature of the fit rather than visual similarity. This response pattern was replicated with Korean‐speaking adults, but English‐speaking adults showed no sensitivity to change in fit for either event. These findings suggest that language development links linguistic forms to universal, pre‐existing representations of meaning, and that linguistic experience can shape sensitivity to distinctions that are marked in one's native language.     

The eye of the retriever: developing episodic memory mechanisms in preverbal infants assessed through pupil dilation

Studying memory in infants can be challenging, as they cannot express their subjective recollection verbally. In this study we use a novel method with which we can assess episodic recognition memory through pupillometry, using identical procedures and stimuli for infants and adults. In three experiments of 4‐ and 7‐month‐old infants, and adults we show that the adult pupillary response is larger to previously seen than to never seen items (old/new effect). Pupil dilations index subjective memory experience in adults, producing distinct pupil dilations to items judged as remembered, familiar, and new, regardless of actual previous exposure (Experiment 1). Seven‐month‐old infants demonstrate a clear pupillary old/new effect, very similar to that of adults (Experiment 2), whereas 4‐month‐olds do not demonstrate such an effect (Experiment 3). Our findings suggest that the mnemonic mechanisms that serve infants' and adults' episodic recognition memory are more similar than previously asserted: they are not fully developed at 4 months of age but that there is contiguity in human episodic memory development from 7 months of age.