Do you understand what I want to tell you? Early sensitivity in bilinguals' iconic gesture perception and production

Previous research has shown differences in monolingual and bilingual communication. We explored whether monolingual and bilingual pre‐schoolers (N = 80) differ in their ability to understand others' iconic gestures (gesture perception) and produce intelligible iconic gestures themselves (gesture production) and how these two abilities are related to differences in parental iconic gesture frequency. In a gesture perception task, the experimenter replaced the last word of every sentence with an iconic gesture. The child was then asked to choose one of four pictures that matched the gesture as well as the sentence. In a gesture production task, children were asked to indicate ‘with their hands’ to a deaf puppet which objects to select. Finally, parental gesture frequency was measured while parents answered three different questions. In the iconic gesture perception task, monolingual and bilingual children did not differ. In contrast, bilinguals produced more intelligible gestures than their monolingual peers. Finally, bilingual children's parents gestured more while they spoke than monolingual children's parents. We suggest that bilinguals' heightened sensitivity to their interaction partner supports their ability to produce intelligible gestures and results in a bilingual advantage in iconic gesture production.     

Monolingual and bilingual children's social preferences for monolingual and bilingual speakers

Past research has shown that young monolingual children exhibit language‐based social biases: they prefer native language to foreign language speakers. The current research investigated how children's language preferences are influenced by their own bilingualism and by a speaker's bilingualism. Monolingual and bilingual 4‐ to 6‐year‐olds heard pairs of adults (a monolingual and a bilingual, or two monolinguals) and chose the person with whom they wanted to be friends. Whether they were from a largely monolingual or a largely bilingual community, monolingual children preferred monolingual to bilingual speakers, and native language to foreign language speakers. In contrast, bilingual children showed similar affiliation with monolingual and bilingual speakers, as well as for monolingual speakers using their dominant versus non‐dominant language. Exploratory analyses showed that individual bilinguals displayed idiosyncratic patterns of preference. These results reveal that language‐based preferences emerge from a complex interaction of factors, including preference for in‐group members, avoidance of out‐group members, and characteristics of the child as they relate to the status of the languages within the community. Moreover, these results have implications for bilingual children's social acceptance by their peers.     

How many fingers am I holding up? The answer depends on children's language background

Monolingual English‐speaking preschool children tend to process number gestures as unanalyzed wholes rather than use the one‐to‐one (finger‐to‐quantity) correspondence. By school age, however, children can use the one‐to‐one correspondence. The purpose of the present studies was to test whether children learn one‐to‐one correspondence through exposure to a variety of finger configurations to convey a single quantity. In Study 1, we compared children with exposure to multiple one‐to‐one configurations, that is, French‐English and German‐English bilingual children, to English monolingual children who see consistent representations. As predicted, the bilingual children performed better in interpreting unconventional number gestures. In Study 2, we compared Chinese‐English bilingual children who knew arbitrary one‐handed Chinese numbers gestures for quantities 6–10 to Chinese‐English bilingual children who did not know these gestures, as well as to monolingual English speakers. Chinese‐English bilinguals who knew the arbitrary gestures were more likely to interpret unconventional gestures arbitrarily (i.e., influenced by the written and/or Chinese gesture forms). These children did not differ from English monolinguals in the interpretation of unconventional gestures. These results are consistent with the argument that children can become sensitive to the one‐to‐one correspondence in number gestures with exposure to multiple configurations for the same quantity.     

Spanish-speaking caregivers’ use of referential labels with toddlers is a better predictor of later vocabulary than their use of referential gestures

Variation in how frequently caregivers engage with their children is associated with variation in children's later language outcomes. One explanation for this link is that caregivers use both verbal behaviors, such as labels, and non-verbal behaviors, such as gestures, to help children establish reference to objects or events in the world. However, few studies have directly explored whether language outcomes are more strongly associated with referential behaviors that are expressed verbally, such as labels, or non-verbally, such as gestures, or whether both are equally predictive. Here, we observed caregivers from 42 Spanish-speaking families in the US engage with their 18-month-old children during 5-min lab-based, play sessions. Children's language processing speed and vocabulary size were assessed when children were 25 months. Bayesian model comparisons assessed the extent to which the frequencies of caregivers’ referential labels, referential gestures, or labels and gestures together, were more strongly associated with children's language outcomes than a model with caregiver total words, or overall talkativeness. The best-fitting models showed that children who heard more referential labels at 18 months were faster in language processing and had larger vocabularies at 25 months. Models including gestures, or labels and gestures together, showed weaker fits to the data. Caregivers’ total words predicted children's language processing speed, but predicted vocabulary size less well. These results suggest that the frequency with which caregivers of 18-month-old children use referential labels, more so than referential gestures, is a critical feature of caregiver verbal engagement that contributes to language processing development and vocabulary growth.

Research Highlights

• We examined the frequency of referential communicative behaviors, via labels and/or gestures, produced by caregivers during a 5-min play interaction with their 18-month-old children.
• We assessed predictive relations between labels, gestures, their combination, as well as total words spoken, and children's processing speed and vocabulary growth at 25 months.
• Bayesian model comparisons showed that caregivers’ referential labels at 18 months best predicted both 25-month vocabulary measures, although total words also predicted later processing speed.
• Frequent use of referential labels by caregivers, more so than referential gestures, is a critical feature of communicative behavior that supports children's later vocabulary learning.

     

The principles of conventionality and contrast in word learning: an empirical examination

In Study 1, 4-year-olds avoided 2 names for an object when exposed to a common or a proper noun in a puppet's presence or to a common noun in a puppet's absence, but not when exposed to a proper noun in a puppet's absence. In Study 2, 3-year-olds avoided 2 names for an object when the requester for the referent of a second label in a different language was bilingual and present during naming, but not when the speaker was bilingual but absent or monolingual. Study 3 followed up on the results of the first 2 studies. When children could assume that the puppet knew the name the experimenter used, they inferred that the puppet's use of a different name implied a different referential intent.     

The chimpanzee mind: in search of the evolutionary roots of the human mind

One advantage of living in a social group is the opportunity to use information provided by other individuals. Social information can be based on cues provided by a conspecific or even by a heterospecific individual (e.g., gaze direction, vocalizations, pointing gestures). Although the use of human gaze and gestures has been extensively studied in primates, and is increasingly studied in other mammals, there is no documentation of birds using these cues in a cooperative context. In this study, we tested the ability of three African gray parrots to use different human cues (pointing and/or gazing) in an object-choice task. We found that one subject spontaneously used the most salient pointing gesture (looking and steady pointing with hand at about 20 cm from the baited box). The two others were also able to use this cue after 15 trials. None of the parrots spontaneously used the steady gaze cues (combined head and eye orientation), but one learned to do so effectively after only 15 trials when the distance between the head and the baited box was about 1 m. However, none of the parrots were able to use the momentary pointing nor the distal pointing and gazing cues. These results are discussed in terms of sensitivity to joint attention as a prerequisite to understand pointing gestures as it is to the referential use of labels.     

Infants' Understanding of Looking,Pointing, and Reaching as Cues to Goal-Directed Action

Phillips, Wellman, and Spelke (2002) provided experimental evidence indicating that by the age of 12 months infants use information about an adult's gaze-direction and emotional expression to predict action. We investigate the generality of this ability, using Phillips et al.'s paradigm across different referential gestures. If infants have a rich concept of people as intentional agents, they should encode the person-goal relation and predict action from a variety of referential gestures (such as looking and pointing), as well as from (goal-directed) reaching and grasping actions. Results of Studies 1 and 2 (within-subjects design) and Study 3 (between-subjects design) converge in indicating that Phillips et al.'s basic finding generalizes to reach-and-gaze as cue condition. In Study 3b generalization was demonstrated for point-and-gaze as cue condition. Whereas these findings suggest a general understanding of referential intent at 12 months, a control experiment (Study 4) showed that infants' action expectations could be reversed following a psychologically inconsistent habituation phase (actor points at Object A and subsequently picks up Object B) in the point-and-gaze condition, although no such reversal was obtained in the reach-and-gaze condition. These findings indicate that 1-year-old infants have well-established expectations about action goals signaled by an actor's gaze-direction and reaching and grasping movements but that an understanding of pointing as a cue to action intentions may develop later and follow a different route of acquisition.     

Olive baboons communicate intentionally by pointing

A pointing gesture creates a referential triangle that incorporates distant objects into the relationship between the signaller and the gesture’s recipient. Pointing was long assumed to be specific to our species. However, recent reports have shown that pointing emerges spontaneously in captive chimpanzees and can be learned by monkeys. Studies have demonstrated that both human children and great apes use manual gestures (e.g. pointing), and visual and vocal signals, to communicate intentionally about out-of-reach objects. Our study looked at how monkeys understand and use their learned pointing behaviour, asking whether it is a conditioned, reinforcement-dependent response or whether monkeys understand it to be a mechanism for manipulating the attention of a partner (e.g. a human). We tested nine baboons that had been trained to exhibit pointing, using operant conditioning. More specifically, we investigated their ability to communicate intentionally about the location of an unreachable food reward in three contexts that differed according to the human partner’s attentional state. In each context, we quantified the frequency of communicative behaviour (auditory and visual signals), including gestures and gaze alternations between the distal food and the human partner. We found that the baboons were able to modulate their manual and visual communicative signals as a function of the experimenter’s attentional state. These findings indicate that monkeys can intentionally produce pointing gestures and understand that a human recipient must be looking at the pointing gesture for them to perform their attention-directing actions. The referential and intentional nature of baboons’ communicative signalling is discussed.     

Inferring the goals of a nonhuman agent

Johnson, Slaughter, and Carey [Dev. Sci. 1 (1998) 233.] used infants' ability to follow the ‘gaze’ of novel objects to claim that infants' recognition of mentalistic agents is not isomorphic with person recognition but rather based on a set of nonarbitrary object recognition cues including the presence of a face and the ability to interact contingently with other agents. The current studies extend these findings with data based on infant imitation and the production of communicative gestures. The first study replicated Meltzoff's [Dev. Psychol. 31 (1995) 838.] reenactment of goals paradigm with a novel, nonhuman agent. Fifteen-month-olds were found to reenact both the completed and uncompleted/unseen goals of a novel object that had a face and interacted contingently with the experimenter and infant. Concurrently, infants directed many communicative gestures at the object. A second study excluded the possibility that the communicative gestures apparently directed at the object in Study 1 were in fact imitations of the experimenter's own behavior. The suggestion that novel, nonhuman objects are capable of eliciting such divergent behaviors as gaze-following, goal reenactment, and communicative gestures from infants, supports the claim that all of these behaviors are mediated by a central conceptual notion of mentalistic being, at least by the ages studied, and that that concept is not isomorphic with the concept person.     

Infants’ intentionally communicative vocalizations elicit responses from caregivers and are the best predictors of the transition to language: A longitudinal investigation of infants’ vocalizations,gestures and word production

What aspects of infants’ prelinguistic communication are most valuable for learning to speak, and why? We test whether early vocalizations and gestures drive the transition to word use because, in addition to indicating motoric readiness, they (a) are early instances of intentional communication and (b) elicit verbal responses from caregivers. In study 1, 11 month olds (N = 134) were observed to coordinate vocalizations and gestures with gaze to their caregiver's face at above chance rates, indicating that they are plausibly intentionally communicative. Study 2 tested whether those infant communicative acts that were gaze‐coordinated best predicted later expressive vocabulary. We report a novel procedure for predicting vocabulary via multi‐model inference over a comprehensive set of infant behaviours produced at 11 and 12 months (n = 58). This makes it possible to establish the relative predictive value of different behaviours that are hierarchically organized by level of granularity. Gaze‐coordinated vocalizations were the most valuable predictors of expressive vocabulary size up to 24 months. Study 3 established that caregivers were more likely to respond to gaze‐coordinated behaviours. Moreover, the dyadic combination of infant gaze‐coordinated vocalization and caregiver response was by far the best predictor of later vocabulary size. We conclude that practice with prelinguistic intentional communication facilitates the leap to symbol use. Learning is optimized when caregivers respond to intentional vocalizations with appropriate language.     

Individual differences in the linguistic competence of referential and expressive subjects

The aim of this work was to examine individual differences in referential and expressive style through a longitudinal study. The composition of the first 50 words, communicative gestures, the conversational style of dyads and the percentage of vocabulary produced from 12 to 24 month-olds were analyzed. The vocabulary was collected through interviews to parents and sessions of mother-infant interaction in the laboratory. Significant differences in the proportion of common nouns and frozen phrases between referential and expressive children in the frequency of communicative gestures and style conversation were found. Thus, referential children and their mothers used more pointing gestures than the expressive children and their mothers. Additionally, mothers of referential children used completing more frequently.     

One-year-olds comprehend the communicative intentions behind gestures in a hiding game

This study explored infants' ability to infer communicative intent as expressed in non-linguistic gestures. Sixty children aged 14, 18 and 24 months participated. In the context of a hiding game, an adult indicated for the child the location of a hidden toy by giving a communicative cue: either pointing or ostensive gazing toward the container containing the toy. To succeed in this task children had to do more than just follow the point or gaze to the target container. They also had to infer that the adult's behaviour was relevant to the situation at hand - she wanted to inform them that the toy was inside the container toward which she gestured. Children at all three ages successfully used both types of cues. We conclude that infants as young as 14 months of age can, in some situations, interpret an adult behaviour as a relevant communicative act done for them.     

Once a French Speaker,Always a French Speaker? Bilingual Children's Thinking About the Stability of Language

Despite early emerging and impressive linguistic abilities, young children demonstrate ostensibly puzzling beliefs about the nature of language. In some circumstances monolingual children even express the belief that an individual's language is more stable than her race. The present research investigated bilingual children's thinking about the relative stability of language and race (Kinzler & Dautel, 2012). Five‐to six‐year‐old bilingual children were asked to judge whether a target child who varied in race (White or Black) and language (English or French) would grow up to be an adult who maintained the target child's race or her language. Similar to many monolingual children, a heterogeneous group of bilingual children on average chose the language‐match. Yet French‐English bilingual children were relatively more likely to choose the race‐match, especially when tested in their non‐dominant language. Specific experience with relevant languages, and communicating in a non‐dominant language, may contribute to children's developing metalinguistic success and their thinking about social categorization.     

Monolingual but not bilingual infants demonstrate racial bias in social cue use

Bilingualism exerts early and pervasive effects on cognition, observable in infancy. Thus far, investigations of infant bilingual cognition have focused on sensitivity to visual memory, executive function, and linguistic sensitivity. Much less research has focused on how bilingualism impacts processing of social cues. The present study sought to investigate whether bilingualism modulates the expression of one aspect of social processing: early racial bias. Using a gaze‐following paradigm, we investigated whether 18‐ to 20‐month‐old monolingual and bilingual infants favored their own race. Results demonstrated that monolingual infants favored their own race in following a model whose direction of gaze signaled an event. In contrast, bilingual infants demonstrated race‐neutral gaze‐following patterns, relying more heavily on the reliability of the behavior of the model over race. Findings suggest that bilingualism may have protective effects against the early emergence of racial bias.     

Gestures and Phases: The Dynamics of Speech-Hand Communication

We investigated how a listener's perceived meaning of a spoken sentence is influenced by the relative timing between a speaker's speech and accompanying hand gestures. Participants viewed a computer-animated character who uttered the phrase, “Put the book there now.” while executing a simple right-handed beat gesture whose location relative to the utterance was precisely controlled in a frame-by-frame fashion. The participant's task consisted of making a judgment about two related aspects of the actor's perceived speech: (a) Which word was emphasized? and (b) How clear was the emphasis? That is, did it make sense? The results revealed that the perceived emphasis was determined by the timing (phasing) of the speaker's hand gesture. Furthermore, the clarity of the perceived emphasis (i.e., meaningfulness) was influenced by the affordances in the immediate environment of the speaker. Discussion addresses the primacy of ostensive specification and gesture in communicative events, the dynamics of speech-hand coordination during both actual and virtual dialogue, and the role of environmental affordances in grounding informative communicative acts in the ecology of organism-environment dynamics.     

The role of type and token frequency in using past tense morphemes correctly

Type and token frequency have been thought to be important in the acquisition of past tense morphology, particularly in differentiating regular and irregular forms. In this study we tested the role of frequency in two ways: (1) in bilingual children, who typically use and hear either language less often than monolingual children and (2) cross-linguistically: French and English have different patterns of frequency of regular/irregular verbs. Ten French-English bilingual children, 10 French monolingual and 10 English monolingual children between 4 and 6 years watched a cartoon and re-told the story. The results demonstrated that the bilingual children were less accurate than the monolingual children. Their accuracy in both French and English regular and irregular verbs corresponded to frequency in the input language. These results are consistent with the hypothesis that children learn past tense morphemes by analogy with other words in their vocabularies. We propose a developmental sequence based on conservative generalization across a growing set of verbs.     

Two‐year‐old children but not domestic dogs understand communicative intentions without language,gestures, or gaze

Infants can see someone pointing to one of two buckets and infer that the toy they are seeking is hidden inside. Great apes do not succeed in this task, but, surprisingly, domestic dogs do. However, whether children and dogs understand these communicative acts in the same way is not yet known. To test this possibility, an experimenter did not point, look, or extend any part of her body towards either bucket, but instead lifted and shook one via a centrally pulled rope. She did this either intentionally or accidentally, and did or did not address her act to the subject using ostensive cues. Young 2‐year‐old children but not dogs understood the experimenter's act in intentional conditions. While ostensive pulling of the rope made no difference to children's success, it actually hindered dogs' performance. We conclude that while human children may be capable of inferring communicative intent from a wide variety actions, so long as these actions are performed intentionally, dogs are likely to be less flexible in this respect. Their understanding of communicative intention may be more dependent upon bodily markers of communicative intent, including gaze, orientation, extended limbs, and vocalizations. This may be because humans have come under selective pressure to develop skills for communicating with absent interlocutors – where bodily co‐presence is not possible.     

Attentional control in early and later bilingual children

We examined differences in attentional control among school-age children who were monolingual English speakers, early Spanish-English bilinguals (who began speaking both languages by age 3), and later Spanish-English bilingual children (who began speaking English after age 3). Children's attentional control was tested using the Attention Network Test (ANT). All language groups performed equally on ANT networks; however, when controlling for age and verbal ability, groups differed significantly on reaction time. Early bilingual children responded faster on the ANT compared to both monolingual and later bilingual children, suggesting an attentional monitoring advantage for early bilinguals. These results add to evidence of advantaged cognitive functioning among bilinguals and are consistent with the possibility that children who begin speaking a second language earlier in childhood have greater advantages, due either to effects of acquiring a second language earlier or to longer duration of bilingual experience.     

Spontaneous pointing by bottlenose dolphins (Tursiops truncatus)

Two bottlenose dolphins (Tursiops truncatus) participating in a symbolic communication project spontaneously developed behaviors that resembled pointing and gaze alternation. The dolphins' behavior demonstrated several features reminiscent of referential communicative behavior. It was triadic, involving a signaler, receiver, and referent. It was also indicative, specifying a focus of attention. The dolphins' points were distinct from the act of attending to or acting on objects. Spontaneous dolphin pointing was influenced by the presence of a potential receiver, and the distance between that receiver and the dolphin. These findings suggest that dolphins are capable of producing referential gestures. Accepted after revision: 14 August 2001 Electronic Publication     

The impact of bilingual environments on selective attention in infancy

Bilingualism has been observed to influence cognitive processing across the lifespan but whether bilingual environments have an effect on selective attention and attention strategies in infancy remains an unresolved question. In Study 1, infants exposed to monolingual or bilingual environments participated in an eye‐tracking cueing task in which they saw centrally presented stimuli followed by a target appearing on either the left or right side of the screen. Halfway through the trials, the central stimuli reliably predicted targets' locations. In Study 2, the first half of the trials consisted of centrally presented cues that predicted targets' locations; in the second half, the cue–target location relation switched. All infants performed similarly in Study 1, but in Study 2 infants raised in bilingual, but not monolingual, environments were able to successfully update their expectations by making more correct anticipatory eye movements to the target and expressing faster reactive eye latencies toward the target in the post‐switch condition. The experience of attending to a complex environment in which infants simultaneously process and contrast two languages may account for why infants raised in bilingual environments have greater attentional control than those raised in monolingual environments.