Development of adaptive communication skills in infants of blind parents.
ABSTRACT: A fundamental question about the development of communication behavior in early life is how infants acquire adaptive communication behavior that is well-suited to their individual social environment, and how the experience of parent-child communication affects this development. The current study investigated how infants develop communication skills when their parents are visually impaired and cannot see their infants' eye gaze. We analyzed 6-min video recordings of naturalistic interaction between 14 sighted infants of blind parents (SIBP) with (a) their blind parent, and (b) a sighted experimenter. Data coded from these interactions were compared with those from 28 age-matched sighted infants of sighted parents (controls). Each infant completed two visits, at 6-10 months and 12-16 months of age. Within each interaction sample, we coded the function (initiation or response) and form (face gaze, vocalization, or action) of each infant communication behavior. When interacting with their parents, SIBP made relatively more communicative responses than initiations, and used more face gaze and fewer actions to communicate, than did controls. When interacting with a sighted experimenter, by contrast, SIBP made slightly (but significantly) more communicative initiations than controls, but otherwise used similar forms of communication. The differential communication behavior by infants of blind versus sighted parents was already apparent by 6-10 months of age, and was specific to communication with the parent. These results highlight the flexibility in the early development of human communication behavior, which enables infants to optimize their communicative bids and methods to their unique social environment. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Project description:A fundamental question in functional brain development is how the brain acquires specialised processing optimised for its individual environment. The current study is the first to demonstrate that distinct experience of eye gaze communication, due to the visual impairment of a parent, affects the specificity of brain responses to dynamic gaze shifts in infants. Event-related potentials (ERPs) from 6 to 10 months old sighted infants with blind parents (SIBP group) and control infants with sighted parents (CTRL group) were recorded while they observed a face with gaze shifting Toward or Away from them. Unlike the CTRL group, ERPs of the SIBP group did not differentiate between the two directions of gaze shift. Thus, selective brain responses to perceived gaze shifts in infants may depend on their eye gaze communication experience with the primary caregiver. This finding highlights the critical role of early communicative experience in the emerging functional specialisation of the human brain.
Project description:Eye gaze is a key channel of non-verbal communication in humans. Eye contact with others is present from birth, and eye gaze processing is crucial for social learning and adult-infant communication. However, little is known about the effect of selectively different experience of eye contact and gaze communication on early social and communicative development. To directly address this question, we assessed 14 sighted infants of blind parents (SIBPs) longitudinally at 6-10 and 12-16 months. Face scanning and gaze following were assessed using eye tracking. In addition, naturalistic observations were made when the infants were interacting with their blind parent and with an unfamiliar sighted adult. Established measures of emergent autistic-like behaviors and standardized tests of cognitive, motor, and linguistic development were also collected. These data were then compared with those obtained from a group of infants of sighted parents. Despite showing typical social skills development overall, infants of blind parents allocated less attention to adult eye movements and gaze direction, an effect that increased between 6-10 and 12-16 months of age. The results suggest that infants adjust their use of adults' eye gaze depending on gaze communication experience from early in life. The results highlight that human functional brain development shows selective experience-dependent plasticity adaptive to the individual's specific social environment.
Project description:Gaze following plays a role in parent-infant communication and is a key mechanism by which infants acquire information about the world from social input. Gaze following in Deaf infants has been understudied. Twelve Deaf infants of Deaf parents (DoD) who had native exposure to American Sign Language (ASL) were gender-matched and age-matched (±7 days) to 60 spoken-language hearing control infants. Results showed that the DoD infants had significantly higher gaze-following scores than the hearing infants. We hypothesize that in the absence of auditory input, and with support from ASL-fluent Deaf parents, infants become attuned to visual-communicative signals from other people, which engenders increased gaze following. These findings underscore the need to revise the 'deficit model' of deafness. Deaf infants immersed in natural sign language from birth are better at understanding the signals and identifying the referential meaning of adults' gaze behavior compared to hearing infants not exposed to sign language. Broader implications for theories of social-cognitive development are discussed. A video abstract of this article can be viewed at https://youtu.be/QXCDK_CUmAI.
Project description:Acquisition of walking changes not only infants' locomotion itself but also infants' exploratory behavior and social interaction, such as gaze communication. To understand the ecological context in which gaze communication occurs and how it changes with walking development from the point of view of the spatial arrangement of infants, parents, and objects, we analyzed longitudinal data of daily eye contact scenes recorded from head-mounted eye trackers worn by parents as infants grew from 10 to 15.5 months, focusing on infant-parent distance and the number of objects between the dyad. A Bayesian state-space model revealed that the interpersonal distance at which infants initiated eye contact with their parents increased with the time ratio of walking to crawling. This result could not be explained by the developmental change in the amount of time that the infants were far from the parents, which is not limited to the gaze communication context. Moreover, the interpersonal distance at which the parents initiated eye contact with the infants did not increase with the time ratio of walking to crawling. The number of objects on the floor between infants and parents at the time of eye contact increased with interpersonal distance. Taken together, these results indicate that the transition from crawling to walking changes the ecological context in which infants initiate gaze communication to a visual environment characterized by a larger interpersonal distance and, therefore, more objects cluttered between the dyad. The present study has wider implications for the developmental change of shared attention in conjunction with walking development.
Project description:Use of eye-gaze assistive technology (EGAT) provides children/youths with severe motor and speech impairments communication opportunities by using eyes to control a communication interface on a computer. However, knowledge about how using EGAT contributes to communication and influences dyadic interaction remains limited.<h4>Aim</h4>By video-coding dyadic interaction sequences, this study investigates the impacts of employing EGAT, compared to the Non-EGAT condition on the dyadic communicative interaction.<h4>Method</h4>Participants were six dyads with children/youths aged 4-19 years having severe physical disabilities and complex communication needs. A total of 12 film clips of dyadic communication activities with and without EGAT in natural contexts were included. Based on a systematic coding scheme, dyadic communication behaviors were coded to determine the interactional structure and communicative functions. Data were analyzed using a three-tiered method combining group and individual analysis.<h4>Results</h4>When using EGAT, children/youths increased initiations in communicative interactions and tended to provide more information, while communication partners made fewer communicative turns, initiations, and requests compared to the Non-EGAT condition. Communication activities, eye-control skills, and communication abilities could influence dyadic interaction.<h4>Conclusion</h4>Use of EGAT shows potential to support communicative interaction by increasing children's initiations and intelligibility, and facilitating symmetrical communication between dyads.
Project description:Many studies have explored factors which influence gaze-following behavior of young infants. However, the results of empirical studies were inconsistent, and the mechanism underlying the contextual modulation of gaze following remains unclear. In order to provide valuable insight into the mechanisms underlying gaze following, we conducted computational modeling using Q-learning algorithm and simulated the learning process of infant gaze following to suggest a feasible model. In Experiment 1, we simulated how communicative cues and infant internal states affect the learning process of gaze following. The simulation indicated that the model in which communicative cues enhance infant internal states is the most feasible to explain the infant learning process. In Experiment 2, we simulated how individual differences in motivation for communication affect the learning process. The results showed that low motivation for communication can delay the learning process and decrease the frequency of gaze following. These simulations suggest that communicative cues may enhance infants' internal states and promote the development of gaze following. Also, initial social motivation may affect the learning process of social behaviors in the long term.
Project description: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.
Project description:The unique morphology of human eyes enables gaze communication at various ranges of interpersonal distance. Although gaze communication contributes to infants' social development, little is known about how infant-parent distance affects infants' visual experience in daily gaze communication. The present study conducted longitudinal observations of infant-parent face-to-face interactions in the home environment as 5 infants aged from 10 to 15.5 months. Using head-mounted eye trackers worn by parents, we evaluated infants' daily visual experience of 3138 eye contact scenes recorded from the infants' second-person perspective. The results of a hierarchical Bayesian statistical analysis suggest that certain levels of interpersonal distance afforded smooth interaction with eye contact. Eye contacts were not likely to be exchanged when the infant and parent were too close or too far apart. The number of continuing eye contacts showed an inverse U-shaped pattern with interpersonal distance, regardless of whether the eye contact was initiated by the infant or the parent. However, the interpersonal distance was larger when the infant initiated the eye contact than when the parent initiated it, suggesting that interpersonal distance affects the infant's and parent's social look differently. Overall, the present study indicates that interpersonal distance modulates infant-parent gaze communication.
Project description:When infants and adults communicate, they exchange social signals of availability and communicative intention such as eye gaze. Previous research indicates that when communication is successful, close temporal dependencies arise between adult speakers' and listeners' neural activity. However, it is not known whether similar neural contingencies exist within adult-infant dyads. Here, we used dual-electroencephalography to assess whether direct gaze increases neural coupling between adults and infants during screen-based and live interactions. In experiment 1 (n = 17), infants viewed videos of an adult who was singing nursery rhymes with (i) direct gaze (looking forward), (ii) indirect gaze (head and eyes averted by 20°), or (iii) direct-oblique gaze (head averted but eyes orientated forward). In experiment 2 (n = 19), infants viewed the same adult in a live context, singing with direct or indirect gaze. Gaze-related changes in adult-infant neural network connectivity were measured using partial directed coherence. Across both experiments, the adult had a significant (Granger) causal influence on infants' neural activity, which was stronger during direct and direct-oblique gaze relative to indirect gaze. During live interactions, infants also influenced the adult more during direct than indirect gaze. Further, infants vocalized more frequently during live direct gaze, and individual infants who vocalized longer also elicited stronger synchronization from the adult. These results demonstrate that direct gaze strengthens bidirectional adult-infant neural connectivity during communication. Thus, ostensive social signals could act to bring brains into mutual temporal alignment, creating a joint-networked state that is structured to facilitate information transfer during early communication and learning.
Project description:According to the natural pedagogy theory, infant gaze following is based on an understanding of the communicative intent of specific ostensive cues. However, it has remained unclear how eye contact affects this understanding and why it induces gaze following behaviour. In this study, we examined infant arousal in different gaze following contexts and whether arousal levels during eye contact predict gaze following. Twenty-five infants, ages 9-10 months participated in this study. They watched a video of an actress gazing towards one of two objects and then either looking directly into the camera to make eye contact or not showing any communicative intent. We found that eye contact led to an elevation in the infants' heart rates (HRs) and that HR during eye contact was predictive of later gaze following. Furthermore, increases in HR predicted gaze following whether it was accompanied by communicative cues or not. These findings suggest that infant gaze following behaviour is associated with both communicative cues and physiological arousal.