Hand-Eye Coordination Predicts Joint Attention

Does attention sharing support attention focusing? Investigating the link between infants' sustained attention and joint attention with caregivers

Sustained attention in infancy is a known predictor of executive functions, self-regulation, and language. This study investigated the relationship between 9- to 16-month-old infants' sustained attention and joint attention in mother-infant dyads. Data were collected from 98 infants (M(SD) = 11.8(1.3) months) and their mothers. Results showed that joint attention during mother-infant play significantly predicted sustained attention during solo play, after accounting for infant age and socioeconomic status. These cross-sectional findings suggest that joint attention may play a role in supporting sustained attention, though the directionality of this relationship warrants further longitudinal investigation.

The Developmental Origins of Joint Attention: Infants' Early Joint Attention Bids

There are theoretical debates about the definition of joint attention, and empirical debates about when it emerges in development. Here we addressed both debates by investigating the emergence of infants' communicative joint attention bids: looks to their partner's face, accompanied by communicative facial expressions and/or vocalizations, to attempt to initiate joint attention to a referent. We tested 25 infants monthly, longitudinally, between 6 and 10 months using both novel joint attention elicitation tests and free play observations. Even when using a conservative definition of joint attention involving communication, results indicated that a substantial percentage of infants (44%) had already begun to produce joint attention bids by 6 months, with the vast majority (92%) having done so before 9 months. Joint attention bids emerged gradually, with increasing consistency, and were seen earlier in the novel elicitation tests than in free play, suggesting that previous work focusing on free play might have underestimated infants' joint attention. We discuss the implications of these findings for theories of joint attention and communication.

The ECOLANG Multimodal Corpus of adult-child and adult-adult Language

Communication comprises a wealth of multimodal signals (e.g., gestures, eye gaze, intonation) in addition to speech and there is a growing interest in the study of multimodal language by psychologists, linguists, neuroscientists and computer scientists. The ECOLANG corpus provides audiovisual recordings and ELAN annotations of multimodal behaviours (speech transcription, gesture, object manipulation, and eye gaze) by British and American English-speaking adults engaged in semi-naturalistic conversation with their child (N = 38, children 3-4 years old, face-blurred) or a familiar adult (N = 31). Speakers were asked to talk about objects to their interlocutors. We further manipulated whether the objects were familiar or novel to the interlocutor and whether the objects could be seen and manipulated (present or absent) during the conversation. These conditions reflect common interaction scenarios in real-world communication. Thus, ECOLANG provides ecologically-valid data about the distribution and co-occurrence of multimodal signals across these conditions for cognitive scientists and neuroscientists interested in addressing questions concerning real-world language acquisition, production and comprehension, and for computer scientists to develop multimodal language models and more human-like artificial agents.

Looking, pointing, and talking together: How dyads of differential expertise coordinate attention during conversation

When people discuss something that they can both see, their attention becomes increasingly coupled. Previous studies have found that this coupling is temporally asymmetric (e.g., one person leads and one follows) when dyads are assigned conversational roles (e.g., speaker and listener). And while such studies have focused on the coupling of gaze, there is also evidence that people use their hands to coordinate attention. The present study uses a visual task to expand on this past work in two respects. First, rather than assigning conversational roles, participants' background knowledge was manipulated (e.g., expert and novice) to elicit differential roles inherent to the conversation. Second, participants were permitted to gesture freely while interacting. Cross Recurrence Quantification Analysis with data from mobile eye trackers and manually coded pointing gestures revealed that although more knowledgeable participants dominated the dialogue by talking and pointing more, the symmetry of coupled behaviors (gaze and pointing) between participants remained fixed. Asymmetric attentional coupling emerged, although this was dependent on conversational turn taking. Specifically, regardless of background knowledge, the currently speaking participant led attention, both with the eyes and with the hands. These findings suggest stable, turn-dependent interpersonal coupling dynamics, and highlight the role of pointing gestures and conversational turn-taking in multimodal attention coordination.

Implementing mobile eye tracking in psychological research: A practical guide

Eye tracking provides direct, temporally and spatially sensitive measures of eye gaze. It can capture visual attention patterns from infancy through adulthood. However, commonly used screen-based eye tracking (SET) paradigms are limited in their depiction of how individuals process information as they interact with the environment in "real life". Mobile eye tracking (MET) records participant-perspective gaze in the context of active behavior. Recent technological developments in MET hardware enable researchers to capture egocentric vision as early as infancy and across the lifespan. However, challenges remain in MET data collection, processing, and analysis. The present paper aims to provide an introduction and practical guide to starting researchers in the field to facilitate the use of MET in psychological research with a wide range of age groups. First, we provide a general introduction to MET. Next, we briefly review MET studies in adults and children that provide new insights into attention and its roles in cognitive and socioemotional functioning. We then discuss technical issues relating to MET data collection and provide guidelines for data quality inspection, gaze annotations, data visualization, and statistical analyses. Lastly, we conclude by discussing the future directions of MET implementation. Open-source programs for MET data quality inspection, data visualization, and analysis are shared publicly.

Developmental Changes in How Head Orientation Structures Infants' Visual Attention

Most studies of developing visual attention are conducted using screen-based tasks in which infants move their eyes to select where to look. However, real-world visual exploration entails active movements of both eyes and head to bring relevant areas in view. Thus, relatively little is known about how infants coordinate their eyes and heads to structure their visual experiences. Infants were tested every 3 months from 9 to 24 months while they played with their caregiver and three toys while sitting in a highchair at a table. Infants wore a head-mounted eye tracker that measured eye movement toward each of the visual targets (caregiver's face and toys) and how targets were oriented within the head-centered field of view (FOV). With age, infants increasingly aligned novel toys in the center of their head-centered FOV at the expense of their caregiver's face. Both faces and toys were better centered in view during longer looking events, suggesting that infants of all ages aligned their eyes and head to sustain attention. The bias in infants' head-centered FOV could not be accounted for by manual action: Held toys were more poorly centered compared with non-held toys. We discuss developmental factors-attentional, motoric, cognitive, and social-that may explain why infants increasingly adopted biased viewpoints with age.

Interacting with autistic virtual characters: intrapersonal synchrony of nonverbal behavior affects participants' perception

Temporal coordination of communicative behavior is not only located between but also within interaction partners (e.g., gaze and gestures). This intrapersonal synchrony (IaPS) is assumed to constitute interpersonal alignment. Studies show systematic variations in IaPS in individuals with autism, which may affect the degree of interpersonal temporal coordination. In the current study, we reversed the approach and mapped the measured nonverbal behavior of interactants with and without ASD from a previous study onto virtual characters to study the effects of the differential IaPS on observers (N = 68), both with and without ASD (crossed design). During a communication task with both characters, who indicated targets with gaze and delayed pointing gestures, we measured response times, gaze behavior, and post hoc impression formation. Results show that character behavior indicative of ASD resulted in overall enlarged decoding times in observers and this effect was even pronounced in observers with ASD. A classification of observer's gaze types indicated differentiated decoding strategies. Whereas non-autistic observers presented with a rather consistent eyes-focused strategy associated with efficient and fast responses, observers with ASD presented with highly variable decoding strategies. In contrast to communication efficiency, impression formation was not influenced by IaPS. The results underline the importance of timing differences in both production and perception processes during multimodal nonverbal communication in interactants with and without ASD. In essence, the current findings locate the manifestation of reduced reciprocity in autism not merely in the person, but in the interactional dynamics of dyads.

Association between caregiver and infant visual neurocognition

Previous work has shown that caregiver attention shapes visual cognition in infants through dyadic interactions. Is this association measurable when visual cognition is objectively measured in caregivers and infants using comparable experimental paradigms? In the current study, we presented infants (N = 86) and caregivers (N = 78) with age-specific variants of the same preferential looking visual cognition task to investigate whether caregiver visual cognition was associated with their infants' visual cognition. In each trial of the task, two side-by-side flashing displays of coloured shapes were presented. On the 'unchanging' side, the colours of the shapes remained the same. On the 'changing' side, the colour of one shape changed after each flash. Load was varied by changing the number of shapes across trials (low, medium, and high loads). We extracted looking dynamics using video recordings and brain function using functional near-infrared spectroscopy as both infants and caregivers engaged with the task. Change preference (CP) score, which represented the amount of time spent looking at the changing side divided by the total looking duration, showed a load-dependent modulation for both infants and caregivers. Both groups showed the highest CP scores at the low load. Further, higher caregiver CP scores was associated with higher infant CP scores at the low load. Both infants and caregivers engaged canonical regions of the fronto-parietal network involved in visual cognition. Critically, higher caregiver CP scores were associated with greater activation in the left superior parietal lobule in younger infants, a region involved in allocating visuo-spatial attention and working memory maintenance. Further, there was spatial overlap between performance-dependent regions in the right parietal cortex in caregivers and younger infants. Our findings provide first evidence of a heritability-related visual neurocognitive association between caregivers and their children in the first year of life.

Consistency and variability in multimodal parent-child social interaction: An at-home study using head-mounted eye trackers

Real-time attention coordination in parent-toddler dyads is often studied in tightly controlled laboratory settings. These studies have demonstrated the importance of joint attention in scaffolding the development of attention and the types of dyadic behaviors that support early language learning. Little is known about how often these behaviors occur in toddlers' everyday lives. We brought wireless head-mounted eye trackers to families' homes to study the moment-to-moment patterns of toddlers' and parents' visual attention and manual activity in daily routines. Our sample consisted of English- and Spanish-speaking families who all reported being middle- or upper middle-class. Toddlers were 2 to 3 years old. Consistent with the findings from previous laboratory studies, we found variability in how frequently toddlers attended to named objects in two everyday activities-Object Play and Mealtime. We then tested whether parent-toddler joint attention in the seconds before a naming utterance increased toddler's attention on the named object. We found that joint attention accompanied by the attended object being held increased the child's attention to the labeled object during naming. We posit that in the rich, noisy world of toddlers' everyday lives, embodied attention plays a critical role in coordinating dyadic behaviors and creating informative naming moments. Our findings highlight the importance of studying toddlers' natural behavior in the real world. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Infant sustained attention differs by context and social content in the first 2 years of life

Sustained attention (SA) is an endogenous form of attention that emerges in infancy and reflects cognitive engagement and processing. SA is critical for learning and has been measured using different methods during screen-based and interactive contexts involving social and nonsocial stimuli. How SA differs by measurement method, context, and stimuli across development in infancy is not fully understood. This 2-year longitudinal study examines attention using one measure of overall looking behavior and three measures of SA-mean look duration, percent time in heart rate-defined SA, and heart rate change during SA-in N = 53 infants from 1 to 24 months across four unique task conditions: social videos, nonsocial videos, social interactions (face-to-face play), and nonsocial interactions (toy engagement). Results suggest that developmental changes in attention differ by measurement method, task context (screen or interaction), and task stimulus (social or nonsocial). During social interactions, overall looking and look durations declined after age 3-4 months, whereas heart rate-defined attention measures remained stable. All SA measures were greater for videos than for live interaction conditions throughout the first 6 months, but SA to social and nonsocial stimuli within each task context were equivalent. In the second year of life, SA measured with look durations was greater for social videos compared to other conditions, heart rate-defined SA was greater for social videos compared to nonsocial interactions, and heart rate change during SA was similar across conditions. Together, these results suggest that different measures of attention to social and nonsocial stimuli may reflect unique developmental processes and are important to compare and consider together, particularly when using infant attention as a marker of typical or atypical development. RESEARCH HIGHLIGHTS: Attention measure, context, and social content uniquely differentiate developmental trajectories of attention in the first 2 years of life. Overall looking to caregivers during dyadic social interactions declines significantly from 4 to 6 months of age while sustained attention (SA) to caregivers remains stable. Heart rate-defined SA generally differentiates stimulus context where infants show greater SA while watching videos than while engaging with toys.

Effect of online parent training in promoting language development of children with language delay in Hubei province, China

BACKGROUND

Training parents to implement language and communication intervention strategies is an effective approach to promote language development for children with language delay.

AIMS

This study introduces an online parent training program conducted in Hubei province, China, which was designed to help parents of language-delayed children with a diagnosis of autism spectrum disorder (ASD), developmental language disorder (DLD) or global developmental delay (GDD) apply language intervention strategies into daily interactions and promote their children's language development at home.

METHODS & PROCEDURES

The Bethel Hearing and Speaking Training Center Family Training for Early Communication & Language Development (Bethel Family Training Program, BFT) (Bethel HSTC, 2020) was designed to improve the language and communication skills for children with language delay in a naturalistic way. The caregivers (including parents, grandparents and other main caregivers) participated in an 8-h online program, including lectures on milestones in child language development, common misunderstandings of child language development, and three basic family language intervention strategies ('Looking together, playing together, and talking together') incorporating active learning through video analysis and discussion. Tongji Hospital in Hubei then continued with 3 months of online home intervention monitoring to all the caregivers via weekly online Q&As led by BFT certified speech therapists' team. The Gesell Developmental Schedules (GDS) was carried out before the online parent training program and after the 3-month online home intervention monitoring.

OUTCOMES & RESULTS

146 families whose children aged 12-68 months with language delay participated in the online training program. The results of the GDS assessments conducted before and after the program showed that not only did the developmental quotient (DQ) of language improve, but so did the DQ of social behaviour and adaptive behaviour (p < 0.001). There is no between-group difference in the application of three strategies between the ASD group and the DLD or GDD group (p > 0.05). Furthermore, both caregivers' ability to apply 'looking together, playing together, talking together' strategies and the effective interaction time played important roles in improving the child's language abilities.

CONCLUSION & IMPLICATIONS

The online parent training focusing on improving daily interaction with children through speech-language stimulation strategies promoted the development of language skills. It is an economic and practical approach for children with language delay who have limited access to local language intervention programs.

WHAT THIS PAPER ADDS

What is already known on the subject Parent-implemented language intervention is an effective approach at improving children's language development. Telepractice is an appropriate model of service delivery for audiologists and speech-language therapists and may be the primary mode of service delivery or may supplement in-person services. What this paper adds to the existing knowledge This paper explores the effectiveness of an online parent training program and provides new evidence that online training on language support strategies (looking together, playing together, talking together) followed by home intervention monitoring works for Mandarin-speaking children and it is equally effective for children with ASD and non-ASD diagnosis. What are the potential or actual clinical implications of this work? Developmental behavioural paediatricians and speech-language therapists in countries and areas that lack sufficient training resource for every child will have the option to deliver parent training and home intervention monitoring online, which will save time and cost considerably while offering convenience.

Autistic young people adaptively use gaze to facilitate joint attention during multi-gestural dyadic interactions

LAY ABSTRACT

Autistic people have been said to have 'problems' with joint attention, that is, looking where someone else is looking. Past studies of joint attention have used tasks that require autistic people to continuously look at and respond to eye-gaze cues. But joint attention can also be done using other social cues, like pointing. This study looked at whether autistic and non-autistic young people use another person's eye gaze during joint attention in a task that did not require them to look at their partner's face. In the task, each participant worked together with their partner to find a computer-generated object in virtual reality. Sometimes the participant had to help guide their partner to the object, and other times, they followed their partner's lead. Participants were told to point to guide one another but were not told to use eye gaze. Both autistic and non-autistic participants often looked at their partner's face during joint attention interactions and were faster to respond to their partner's hand-pointing when the partner also looked at the object before pointing. This shows that autistic people can and do use information from another person's eyes, even when they don't have to. It is possible that, by not forcing autistic young people to look at their partner's face and eyes, they were better able to gather information from their partner's face when needed, without being overwhelmed. This shows how important it is to design tasks that provide autistic people with opportunities to show what they can do.

Leveraging technological advances to assess dyadic visual cognition during infancy in high- and low-resource settings

Caregiver-infant interactions shape infants' early visual experience; however, there is limited work from low-and middle-income countries (LMIC) in characterizing the visual cognitive dynamics of these interactions. Here, we present an innovative dyadic visual cognition pipeline using machine learning methods which captures, processes, and analyses the visual dynamics of caregiver-infant interactions across cultures. We undertake two studies to examine its application in both low (rural India) and high (urban UK) resource settings. Study 1 develops and validates the pipeline to process caregiver-infant interaction data captured using head-mounted cameras and eye-trackers. We use face detection and object recognition networks and validate these tools using 12 caregiver-infant dyads (4 dyads from a 6-month-old UK cohort, 4 dyads from a 6-month-old India cohort, and 4 dyads from a 9-month-old India cohort). Results show robust and accurate face and toy detection, as well as a high percent agreement between processed and manually coded dyadic interactions. Study 2 applied the pipeline to a larger data set (25 6-month-olds from the UK, 31 6-month-olds from India, and 37 9-month-olds from India) with the aim of comparing the visual dynamics of caregiver-infant interaction across the two cultural settings. Results show remarkable correspondence between key measures of visual exploration across cultures, including longer mean look durations during infant-led joint attention episodes. In addition, we found several differences across cultures. Most notably, infants in the UK had a higher proportion of infant-led joint attention episodes consistent with a child-centered view of parenting common in western middle-class families. In summary, the pipeline we report provides an objective assessment tool to quantify the visual dynamics of caregiver-infant interaction across high- and low-resource settings.

Parent-child sensorimotor coordination in toddlers with and without hearing loss

Infants experience the world through their actions with objects and their interactions with other people, especially their parents. Prior research has shown that school-age children with hearing loss experience poorer quality interactions with typically hearing parents, yet little is known about parent-child interactions between toddlers with hearing loss and their parents early in life. In the current study, we used mobile eye-tracking to investigate parent-child interactions in toddlers with and without hearing loss (mean ages: 19.42 months, SD = 3.41 months). Parents and toddlers engaged in a goal-directed, interactive task that involved inserting coins into a slot and required joint coordination between the parent and the child. Overall, findings revealed that deaf toddlers demonstrate typical action skills in line with their hearing peers and engage in similar interactions with their parents during social interactions. Findings also revealed that deaf toddlers explored objects more and showed more temporal stability in their motor movements (i.e. less variation in their timing across trials) than hearing peers, suggesting further adaptability of the deaf group to their atypical sensory environment rather than poorer coordination. In contrast to previous research, findings suggest an intact ability of deaf toddlers to coordinate their actions with their parents and highlight the adaptability within dyads who have atypical sensory experiences.

Preterm toddlers' joint attention characteristics during dyadic interactions with their mothers and fathers compared to full-term toddlers at age 2 years

The current study investigates Joint Attention (JA) characteristics (duration, frequency, source of initiation, type of JA, agent of termination, missed and unsuccessful episodes) in preterm and full-term toddlers' interactions with their mothers and fathers, separately. Thirty-one singleton full-term (Mage = 24.07 months, SD = 1.45; 13 boys) and 17 singleton preterm toddlers (Madjustedage = 24.72 months, SD = 3.39; 12 boys) participated in the study with both parents. JA episodes were examined during dyadic five-minute free play sessions, were coded second-by-second, and were analysed using two-way mixed ANOVAs. Although the total amount of time spent in JA was not significantly different between the preterm and the full-term groups, JA episodes were more frequent, specifically supported JA episodes, and were more often terminated by the child during parent-preterm toddler interactions. Moreover, preterm toddlers missed their fathers' attempts for JA more often than their mothers' and more often than full-term toddlers missed their fathers' and mothers' bids for JA. Further, regardless of the birth status, toddlers initiated more JA with mothers than fathers, and fathers redirected their child's attention to initiate JA more than mothers. Findings indicate that preterm toddlers may struggle to respond to JA bids, especially with their fathers, and to sustain their attention on a specific object or event during interactions. Preterm toddlers may need more support to engage in JA relative to their full-term peers, and redirecting attention strategy may not be optimal for them. Also, toddlers' JA interactions may be different with their mothers and fathers. Findings contribute to the literature by demonstrating preterm toddlers' JA characteristics with both parents compared to full-term toddlers at age two.

Early development of saliency-driven attention through object manipulation

In the first years of life, infants progressively develop attention selection skills to gather information from visually clustered environments. As young as newborns, infants are sensitive to the distinguished differences in color, orientation, and luminance, which are the components of visual saliency. However, we know little about how saliency-driven attention emerges and develops socially through everyday free-viewing experiences. The present work assessed the saliency change in infants' egocentric scenes and investigated the impacts of manual engagements on infant object looking in the interactive context of object play. Thirty parent-infant dyads, including infants in two age groups (younger: 3- to 6-month-old; older: 9- to 12-month-old), completed a brief session of object play. Infants' looking behaviors were recorded by the head-mounted eye-tracking gear, and both parents' and infants' manual actions on objects were annotated separately for analyses. The present findings revealed distinct attention mechanisms that underlie the hand-eye coordination between parents and infants and within infants during object play: younger infants are predominantly biased toward the characteristics of the visual saliency accompanying the parent's handled actions on the objects; on the other hand, older infants gradually employed more attention to the object, regardless of the saliency in view, as they gained more self-generated manual actions. Taken together, the present work highlights the tight coordination between visual experiences and sensorimotor competence and proposes a novel dyadic pathway to sustained attention that social sensitivity to parents' hands emerges through saliency-driven attention, preparing infants to focus, follow, and steadily track moving targets in free-flow viewing activities.

Theta power relates to infant object encoding in naturalistic mother-infant interactions

This study investigates infants' neural and behavioral responses to maternal ostensive signals during naturalistic mother-infant interactions and their effects on object encoding. Mothers familiarized their 9- to 10-month-olds (N = 35, 17 females, mainly White, data collection: 2018-2019) with objects with or without mutual gaze, infant-directed speech, and calling the infant's name. Ostensive signals focused infants' attention on objects and their mothers. Infant theta activity synchronized and alpha activity desynchronized during interactions compared to a nonsocial resting phase (Cohen' d: 0.49-0.75). Yet, their amplitudes were unrelated to maternal ostensive signals. Ostensive signals did not facilitate object encoding. However, higher infant theta power during encoding predicted better subsequent object recognition. Results strengthen the role of theta-band power for early learning processes.

Social Brain Perspectives on the Social and Evolutionary Neuroscience of Human Language

Human language and social cognition are two key disciplines that have traditionally been studied as separate domains. Nonetheless, an emerging view suggests an alternative perspective. Drawing on the theoretical underpinnings of the social brain hypothesis (thesis of the evolution of brain size and intelligence), the social complexity hypothesis (thesis of the evolution of communication), and empirical research from comparative animal behavior, human social behavior, language acquisition in children, social cognitive neuroscience, and the cognitive neuroscience of language, it is argued that social cognition and language are two significantly interconnected capacities of the human species. Here, evidence in support of this view reviews (1) recent developmental studies on language learning in infants and young children, pointing to the important crucial benefits associated with social stimulation for youngsters, including the quality and quantity of incoming linguistic information, dyadic infant/child-to-parent non-verbal and verbal interactions, and other important social cues integral for facilitating language learning and social bonding; (2) studies of the adult human brain, suggesting a high degree of specialization for sociolinguistic information processing, memory retrieval, and comprehension, suggesting that the function of these neural areas may connect social cognition with language and social bonding; (3) developmental deficits in language and social cognition, including autism spectrum disorder (ASD), illustrating a unique developmental profile, further linking language, social cognition, and social bonding; and (4) neural biomarkers that may help to identify early developmental disorders of language and social cognition. In effect, the social brain and social complexity hypotheses may jointly help to describe how neurotypical children and adults acquire language, why autistic children and adults exhibit simultaneous deficits in language and social cognition, and why nonhuman primates and other organisms with significant computational capacities cannot learn language. But perhaps most critically, the following article argues that this and related research will allow scientists to generate a holistic profile and deeper understanding of the healthy adult social brain while developing more innovative and effective diagnoses, prognoses, and treatments for maladies and deficits also associated with the social brain.

Multimodal pathways to joint attention in infants with a familial history of autism

Joint attention (JA) is an early-developing behavior that allows caregivers and infants to share focus on an object. Deficits in JA, as measured through face-following pathways, are a defining feature of autism spectrum disorder (ASD) and are observable as early as 12 months of age in infants later diagnosed with ASD. However, recent evidence suggests that JA may be achieved through hand-following pathways by children with and without ASD. Development of JA through multimodal pathways has yet to be studied in infants with an increased likelihood of developing ASD. The current study investigated how 6-, 9- and 12-month-old infants with (FH+) and without (FH-) a family history of ASD engaged in JA. Parent-infant dyads played at home while we recorded the interaction over Zoom and later offline coded for hand movements and gaze. FH+ and FH- infants spent similar amounts of time in JA with their parents, but the cues available before JA were different. Parents of FH+ infants did more work to establish JA and used more face-following than hand-following pathways compared to parents of FH- infants, likely reflecting differences in infant motor or social behavior. These results suggest that early motor differences between FH+ and FH- infants may cascade into differences in social coordination.

Opportunities for learning and social interaction in infant sitting: Effects of sitting support, sitting skill, and gross motor delay

The development of independent sitting changes everyday opportunities for learning and has cascading effects on cognitive and language development. Prior to independent sitting, infants experience the sitting position with physical support from caregivers. Why does supported sitting not provide the same input for learning that is experienced in independent sitting? This question is especially relevant for infants with gross motor delay, who require support in sitting for many months after typically developing infants sit independently. We observed infants with typical development (n = 34, ages 4-7 months) and infants with gross motor delay (n = 128, ages 7-16 months) in early stages of sitting development, and their caregivers, in a dyadic play observation. We predicted that infants who required caregiver support for sitting would spend more time facing away from the caregiver and less time contacting objects than infants who could sit independently. We also predicted that caregivers of supported sitters would spend less time contacting objects because their hands would be full supporting their infants. Our first two hypotheses were confirmed; however, caregivers spent surprisingly little time using both hands to provide support, and caregivers of supported sitters spent more time contacting objects than caregivers of independent sitters. Similar patterns were seen in the group of typically developing infants and the infants with motor delay. Our findings suggest that independent sitting and supported sitting provide qualitatively distinct experiences with different implications for social interaction and learning opportunities. HIGHLIGHTS: During seated free play, supported sitters spent more time facing away from their caregivers and less time handling objects than independent sitters. Caregivers who spent more time supporting infants with both hands spent less time handling objects; however, caregivers mostly supported infants with one or no hands. A continuous measure of sitting skill did not uniquely contribute to these behaviors beyond the effect of binary sitting support (supported vs. independent sitter). The pattern of results was similar for typically developing infants and infants with gross motor delay, despite differences in age.

Not all is forgotten: Children's associative matrices for features of a word learning episode

Word learning studies traditionally examine the narrow link between words and objects, indifferent to the rich contextual information surrounding objects. This research examined whether children attend to this contextual information and construct an associative matrix of the words, objects, people, and environmental context during word learning. In Experiment 1, preschool-aged children (age: 3;2-5;11 years) were presented with novel words and objects in an animated storybook. Results revealed that children constructed associations beyond words and objects. Specifically, children attended to and had the strongest associations for features of the environmental context but failed to learn word-object associations. Experiment 2 demonstrated that children (age: 3;0-5;8 years) leveraged strong associations for the person and environmental context to support word-object mapping. This work demonstrates that children are especially sensitive to the word learning context and use associative matrices to support word mapping. Indeed, this research suggests associative matrices of the environment may be foundational for children's vocabulary development.

The road to conventional tool use: Developmental changes in children's material engagement with artifacts in nursery school

The development of tool use in early childhood is a topic of continuing interest in developmental psychology. However, the lack of studies in ecological settings results in many unknowns about how children come to use artifacts according to their cultural function. We report a longitudinal study with 17 sociodemographically diverse children (8 female) attending a nursery school in Madrid (Spain) and their two adult female teachers. Using mixed-effects models and Granger causality analysis, we measured changes in the frequency and duration of children's object uses between 7 and 17 months of age and in the directional influences among pairs of behaviors performed by teachers and children. Results show a clear shift in how children use artifacts. As early as 12 months of age, the frequency of conventional uses outweighs that of all other types of object use. In addition, object uses become shorter in duration with age, irrespective of their type. Moreover, certain teachers' nonlinguistic communicative strategies (e.g., demonstrations of canonical use and placing gestures) significantly influence and promote children's conventional tool use. Findings shed light on how children become increasingly proficient in conventional tool use through interactions with artifacts and others in nursery school.

The temporal structure of parent talk to toddlers about objects

Toddlers learn words in the context of speech from adult social partners. The present studies quantitatively describe the temporal context of parent speech to toddlers about objects in individual real-world interactions. We show that at the temporal scale of a single play episode, parent talk to toddlers about individual objects is predominantly, but not always, clustered. Clustered speech is characterized by repeated references to the same object close in time, interspersed with lulls in speech about the object. Clustered temporal speech patterns mirror temporal patterns observed at longer timescales, and persisted regardless of play context. Moreover, clustered speech about individual novel objects predicted toddlers' learning of those objects' novel names. Clustered talk may be optimal for toddlers' word learning because it exploits domain-general principles of human memory and attention, principles that may have evolved precisely because of the clustered structure of natural events important to humans, including human behavior.

Do you see what I mean?: Using mobile eye tracking to capture parent-child dynamics in the context of anxiety risk

Temperamental behavioral inhibition (BI) is a robust endophenotype for anxiety characterized by increased sensitivity to novelty. Controlling parenting can reinforce children's wariness by rewarding signs of distress. Fine-grained, dynamic measures are needed to better understand both how children perceive their parent's behaviors and the mechanisms supporting evident relations between parenting and socioemotional functioning. The current study examined dyadic attractor patterns (average mean durations) with state space grids, using children's attention patterns (captured via mobile eye tracking) and parental behavior (positive reinforcement, teaching, directives, intrusion), as functions of child BI and parent anxiety. Forty 5- to 7-year-old children and their primary caregivers completed a set of challenging puzzles, during which the child wore a head-mounted eye tracker. Child BI was positively correlated with proportion of parent's time spent teaching. Child age was negatively related, and parent anxiety level was positively related, to parent-focused/controlling parenting attractor strength. There was a significant interaction between parent anxiety level and child age predicting parent-focused/controlling parenting attractor strength. This study is a first step to examining the co-occurrence of parenting behavior and child attention in the context of child BI and parental anxiety levels.

Why the parent's gaze is so powerful in organizing the infant's gaze: The relationship between parental referential cues and infant object looking

Parental scaffolding such as looking at and showing objects has long been considered to be helpful for early attention and language development. However, relatively little is known about how parental social multimodal cues work alone or together in guiding an infant's attention toward the referent items. The present study aims to document the dynamics of social referential input during an interactive play session and specify the different types of social cues in directing infant attention. Forty-three parent-infant dyads (infants aged from 5.0 to 18.0 months) in the U.S. completed a short play session recorded by head-mounted camera with eye-trackers. The present findings suggest that joint attention between parent and infant toward the same referent item often co-occurred with other referential input. Infants were more likely to maintain sustained attention to an object under the circumstance that the parent looked at the same item and named it explicitly. This was not the case when parent object looking accompanied other utterances, like "Look!" or the child's name. The present study highlights the importance of multimodal referential input, which sets up enriched opportunities for children to become sensitive to social input and develop sustained attention for further learning.

Children with ASD establish joint attention during free-flowing toy play without face looks

Children's ability to share attention with another person (i.e., achieve joint attention) is critical for learning about their environments in general^1-3 and supporting language and object word learning in particular.^1,4-14 While joint attention (JA) as it pertains to autism spectrum disorder (ASD) is often more narrowly operationalized as arising from eye gaze or explicit pointing cues alone,^2,5,10,15-19 recent evidence demonstrates that JA in natural environments can be achieved more broadly through multiple other pathways beyond gaze and gestures.^2,4,20-31 Here, we use dual head-mounted eye tracking to examine pathways into and characteristics of JA episodes during free-flowing parent-child toy play, comparing children with ASD to typically developing (TD) children. Moments of JA were defined objectively as both the child's and parent's gaze directed to the same object at the same time. Consistent with previous work in TD children,^{4,21,25,30-32} we found that both TD and ASD children rarely look at their parent's face in this unstructured free play context. Nevertheless, both groups achieved similarly high rates of JA that far exceeded chance, suggesting the use of alternative pathways into JA. We characterize these alternate pathways, find they occur at similar levels across both groups, and achieve similar ends: namely, for both groups, targets of JA are named more frequently by parents in those moments than non-jointly attended objects. These findings broaden the conceptualization of JA abilities and impairment in ASD and raise questions regarding the mechanistic role of the face-gaze-mediated JA pathway in ASD.

When it pays off to take a look: Infants learn to follow an object's motion with their gaze-Especially if it features eyes

Social cues and instrumental learning are two aspects potentially fostering early gaze following. We systematically investigated the influence of social features (schematic eyes vs. reverse-contrast eyes) and gaze-contingent reinforcement (elicited vs. not elicited) on 4-month-olds' learning to attend to gaze-cued objects. In 4 experiments, we tested infants' (N = 74) gaze following of a turning block with schematic or reverse-contrast eyes. In Experiments 1 and 2, infants could elicit an attractive animation in a training phase via interactive eye tracking by following the turning of the block. Experiments 3 and 4 were yoked controls without contingent reinforcement. Infants did not spontaneously follow the motion of the block. Four-month-olds always followed the block after training when it featured schematic eyes. When the block featured reverse-contrast eyes, the training phase only affected infants' looking behavior without reinforcement. While speaking to a certain degree of plasticity, findings stress the importance of eyes for guiding infants' attention.

Infants' object interactions are long and complex during everyday joint engagement

As infants interact with the object world, they generate rich information about object properties and functions. Much of infant learning unfolds in the presence of caregivers, who talk about and act on the objects of infant play. Does mother joint engagement correspond to real-time changes in the complexity and duration of infant object interactions? We observed thirty-eight mothers and their first-born infants (cross-sectional, 13, 18, and 23 months) during 2 hours of everyday activity as infants freely navigated their home environments. Behavioral coding explored thousands of infant object interactions within and outside mother joint engagement. Object interactions involving exclusively simple play were shorter than complex play bouts. Critically, mothers' multimodal input (i.e., touching/gesturing toward and talking about the focal object) corresponded with more complex and longer play bouts than when mothers provided no input. Bouts involving complex play and multimodal input lasted 7.5 times longer than simple play bouts absent mother input. Moreover, "action-orienting talk" (e.g., "Twist it", "Feed dolly"), rather than talk per se, corresponded with longer bout duration and complexity. Notably, the association between joint engagement and play duration was not a function of mothers having more time to join. Analyses that eliminated short infant bouts and considered the timing of mothers' behaviors confirmed that mother input "extended" the duration of play bouts. As infants actively explore their environments, their object interactions change moment to moment in the presence of mothers' multimodal engagement. RESEARCH HIGHLIGHTS Mothers and infants were videorecorded for 2 hours at home; researchers coded infants' object interactions and mothers' behaviors (verbal, manual) toward the focal object. Mothers' multimodal joint engagement (i.e., coordinated manual and verbal input) was associated with long and complex infant object interactions. The pragmatics of mothers' talk-namely action-orienting language-related to the duration and complexity of infant object bouts beyond talk per se. Infants' object interactions change in complexity and duration in line with maternal joint engagement, indicating potential mechanisms of real-time learning. This article is protected by copyright. All rights reserved.

Large-scale assessment of 7-11-year-olds' cognitive and sensorimotor function within the Born in Bradford longitudinal birth cohort study

Background: Cognitive ability and sensorimotor function are crucial aspects of children's development, and are associated with physical and mental health outcomes and educational attainment. This paper describes cross-sectional sensorimotor and cognitive function data collected on over 15,000 children aged 7-10 years, collected as part of the Born in Bradford (BiB) longitudinal birth-cohort study. Methodological details of the large-scale data collection process are described, along with initial analyses of the data involving the relationship between cognition/sensorimotor ability and age and task difficulty, and associations between tasks. Method: Data collection was completed in 86 schools between May 2016 and July 2019. Children were tested at school, individually, using a tablet computer with a digital stylus or finger touch for input. Assessments comprised a battery of three sensorimotor tasks (Tracking, Aiming, & Steering) and five cognitive tasks (three Working Memory tasks, Inhibition, and Processing Speed), which took approximately 40 minutes. Results: Performance improved with increasing age and decreasing task difficulty, for each task. Performance on all three sensorimotor tasks was correlated, as was performance on the three working memory tasks. In addition, performance on a composite working memory score correlated with performance on both inhibition and processing speed. Interestingly, within age-group variation was much larger than between age-group variation. Conclusions: The current project collected computerised measures of a range of cognitive and sensorimotor functions at 7-10 years of age in over 15,000 children. Performance varied as expected by age and task difficulty, and showed the predicted correlations between related tasks. Large within-age group variation highlights the need to consider the profile of individual children in studying cognitive and sensorimotor development. These data can be linked to the wider BiB dataset including measures of physical and mental health, biomarkers and genome-wide data, socio-demographic information, and routine data from local health and education services.

Beyond screen time: Using head-mounted eye tracking to study natural behavior

Head-mounted eye tracking is a new method that allows researchers to catch a glimpse of what infants and children see during naturalistic activities. In this chapter, we review how mobile, wearable eye trackers improve the construct validity of important developmental constructs, such as visual object experiences and social attention, in ways that would be impossible using screen-based eye tracking. Head-mounted eye tracking improves ecological validity by allowing researchers to present more realistic and complex visual scenes, create more interactive experimental situations, and examine how the body influences what infants and children see. As with any new method, there are difficulties to overcome. Accordingly, we identify what aspects of head-mounted eye-tracking study design affect the measurement quality, interpretability of the results, and efficiency of gathering data. Moreover, we provide a summary of best practices aimed at allowing researchers to make well-informed decisions about whether and how to apply head-mounted eye tracking to their own research questions.

Joint engagement in the home environment is frequent, multimodal, timely, and structured

Infants develop in a social context, surrounded by knowledgeable caregivers who scaffold learning through shared engagement with objects. However, researchers have typically examined joint engagement in structured tasks, where caregivers sit near infants and display frequent, prompt, and multimodal behaviors around the objects of infant action. Which features of joint engagement generalize to the real-world? Despite the importance of joint engagement for infant learning, critical assumptions around joint engagement in everyday interaction remain unexamined. We investigated behavioral and temporal features of joint engagement in the home environment, where objects for play abound and dyad proximity fluctuates. Infant manual actions, mother manual and verbal behaviors, and dyad proximity were coded frame-by-frame from 2-h naturalistic recordings of 13- to 23-month-old infants and their mothers (N = 38). Infants experienced rich, highly structured, multimodal mother input around the objects of their actions. Specifically, joint engagement occurred within seconds of infant action and was amplified in the context of interpersonal proximity. Findings validate laboratory-based research on characteristics of joint engagement while highlighting unique properties around the role of mother-infant proximity and temporal structuring of caregiver input over extended time frames. Implications for the social contexts that support infant learning and development are discussed.

Towards a model of language neurobiology in early development

Understanding language neurobiology in early childhood is essential for characterizing the developmental structural and functional changes that lead to the mature adult language network. In the last two decades, the field of language neurodevelopment has received increasing attention, particularly given the rapid advances in the implementation of neuroimaging techniques and analytic approaches that allow detailed investigations into the developing brain across a variety of cognitive domains. These methodological and analytical advances hold the promise of developing early markers of language outcomes that allow diagnosis and clinical interventions at the earliest stages of development. Here, we argue that findings in language neurobiology need to be integrated within an approach that captures the dynamic nature and inherent variability that characterizes the developing brain and the interplay between behavior and (structural and functional) neural patterns. Accordingly, we describe a framework for understanding language neurobiology in early development, which minimally requires an explicit characterization of the following core domains: i) computations underlying language learning mechanisms, ii) developmental patterns of change across neural and behavioral measures, iii) environmental variables that reinforce language learning (e.g., the social context), and iv) brain maturational constraints for optimal neural plasticity, which determine the infant's sensitivity to learning from the environment. We discuss each of these domains in the context of recent behavioral and neuroimaging findings and consider the need for quantitatively modeling two main sources of variation: individual differences or trait-like patterns of variation and within-subject differences or state-like patterns of variation. The goal is to enable models that allow prediction of language outcomes from neural measures that take into account these two types of variation. Finally, we examine how future methodological approaches would benefit from the inclusion of more ecologically valid paradigms that complement and allow generalization of traditional controlled laboratory methods.

Mapping Word to World in ASL: Evidence from a Human Simulation Paradigm

Across languages, children map words to meaning with great efficiency, despite a seemingly unconstrained space of potential mappings. The literature on how children do this is primarily limited to spoken language. This leaves a gap in our understanding of sign language acquisition, because several of the hypothesized mechanisms that children use are visual (e.g., visual attention to the referent), and sign languages are perceived in the visual modality. Here, we used the Human Simulation Paradigm in American Sign Language (ASL) to determine potential cues to word learning. Sign-naïve adult participants viewed video clips of parent-child interactions in ASL, and at a designated point, had to guess what ASL sign the parent produced. Across two studies, we demonstrate that referential clarity in ASL interactions is characterized by access to information about word class and referent presence (for verbs), similarly to spoken language. Unlike spoken language, iconicity is a cue to word meaning in ASL, although this is not always a fruitful cue. We also present evidence that verbs are highlighted well in the input, relative to spoken English. The results shed light on both similarities and differences in the information that learners may have access to in acquiring signed versus spoken languages.

Early trajectories of motor skills in infant siblings of children with autism spectrum disorder

Delays in motor development are not considered a core feature of autism spectrum disorder (ASD). Yet, recent studies of infant siblings of children with ASD suggest that early delays in motor skills may be associated with later delays in developmental areas considered to be core features of an ASD diagnosis. While these studies demonstrate the longitudinal association between core features and motor delays observed at single time points, there is considerable interest in studying the trajectories of motor development over the first 3 years of life. To accomplish this, we investigated early trajectories of motor development in a cohort of 499 infant siblings of children with ASD and 176 children with no family history of ASD. Data for the current study were drawn from the prospective, multi-site, Canadian Infant Sibling Study. We evaluated trajectories of fine and gross motor development over the first 3 years using group-based trajectory modeling. Our results show that membership for both fine and gross motor trajectory groups was related to expressive language skills, receptive language skills, ASD symptom severity scores, and diagnostic classification at age 3. These results provide evidence that the trajectory of a child's early motor development may have important prognostic implications in ASD.

Automated detections reveal the social information in the changing infant view

How do postural developments affect infants' access to social information? We recorded egocentric and third-person video while infants and their caregivers (N = 36, 8- to 16-month-olds, N = 19 females) participated in naturalistic play sessions. We then validated the use of a neural network pose detection model to detect faces and hands in the infant view. We used this automated method to analyze our data and a prior egocentric video dataset (N = 17, 12-month-olds). Infants' average posture and orientation with respect to their caregiver changed dramatically across this age range; both posture and orientation modulated access to social information. Together, these results confirm that infant's ability to move and act on the world plays a significant role in shaping the social information in their view.

Gaze facilitates responsivity during hand coordinated joint attention

The coordination of attention between individuals is a fundamental part of everyday human social interaction. Previous work has focused on the role of gaze information for guiding responses during joint attention episodes. However, in many contexts, hand gestures such as pointing provide another valuable source of information about the locus of attention. The current study developed a novel virtual reality paradigm to investigate the extent to which initiator gaze information is used by responders to guide joint attention responses in the presence of more visually salient and spatially precise pointing gestures. Dyads were instructed to use pointing gestures to complete a cooperative joint attention task in a virtual environment. Eye and hand tracking enabled real-time interaction and provided objective measures of gaze and pointing behaviours. Initiators displayed gaze behaviours that were spatially congruent with the subsequent pointing gestures. Responders overtly attended to the initiator’s gaze during the joint attention episode. However, both these initiator and responder behaviours were highly variable across individuals. Critically, when responders did overtly attend to their partner’s face, their saccadic reaction times were faster when the initiator’s gaze was also congruent with the pointing gesture, and thus predictive of the joint attention location. These results indicate that humans attend to and process gaze information to facilitate joint attention responsivity, even in contexts where gaze information is implicit to the task and joint attention is explicitly cued by more spatially precise and visually salient pointing gestures.

Parent-Child Joint Behaviors in Novel Object Play Create High-Quality Data for Word Learning

This research takes a dyadic approach to study early word learning and focuses on toddlers' (N = 20, age: 17-23 months) information seeking and parents' information providing behaviors and the ways the two are coupled in real-time parent-child interactions. Using head-mounted eye tracking, this study provides the first detailed comparison of children's and their parents' behavioral and attentional patterns in two free-play contexts: one with novel objects with to-be-learned names (Learning condition) and the other with familiar objects with known names (Play condition). Children and parents in the Learning condition modified their individual and joint behaviors when encountering novel objects with to-be-learned names, which created clearer signals that reduced referential ambiguity and potentially facilitated word learning.

Detecting joint attention events in mother-infant dyads: Sharing looks cannot be reliably identified by naïve third-party observers

Joint attention, or sharing attention with another individual about an object or event, is a critical behaviour that emerges in pre-linguistic infants and predicts later language abilities. Given its importance, it is perhaps surprising that there is no consensus on how to measure joint attention in prelinguistic infants. A rigorous definition proposed by Siposova & Carpenter (2019) requires the infant and partner to gaze alternate between an object and each other (coordination of attention) and exchange communicative signals (explicit acknowledgement of jointly sharing attention). However, Hobson and Hobson (2007) proposed that the quality of gaze between individuals is, in itself, a sufficient communicative signal that demonstrates sharing of attention. They proposed that observers can reliably distinguish “sharing”, “checking”, and “orienting” looks, but the empirical basis for this claim is limited as their study focussed on two raters examining looks from 11-year-old children. Here, we analysed categorisations made by 32 naïve raters of 60 infant looks to their mothers, to examine whether they could be reliably distinguished according to Hobson and Hobson’s definitions. Raters had overall low agreement and only in 3 out of 26 cases did a significant majority of the raters agree with the judgement of the mother who had received the look. For the looks that raters did agree on at above chance levels, look duration and the overall communication rate of the mother were identified as cues that raters may have relied upon. In our experiment, naïve third party observers could not reliably determine the type of look infants gave to their mothers, which indicates that subjective judgements of types of look should not be used to identify mutual awareness of sharing attention in infants. Instead, we advocate the use of objective behaviour measurement to infer that interactants know they are ‘jointly’ attending to an object or event, and believe this will be a crucial step in understanding the ontogenetic and evolutionary origins of joint attention.

An interactionist perspective on the development of coordinated social attention

Infants' ability to coordinate their attention with other people develops profoundly across the first year of life. Mainly based on experimental research focusing on infants' behavior under highly controlled conditions, developmental milestones were identified and explained in the past by prominent theories in terms of the onset of specific cognitive skills. In contrast to this approach, recent longitudinal research challenges this perspective with findings suggesting that social attention develops continuously with a gradual refinement of skills. Informed by these findings, we argue for an interactionist and dynamical systems view that bases observable advances in infant social attention skills on increasingly fine-tuned mutual adjustments in the caregiver-infant dyad, resulting in gradually improving mutual prediction. We present evidence for this view from recent studies leveraging new technologies which afford the opportunity to dynamically track social interactions in real-time. These new technically-sophisticated studies offer unprecedented insights into the dynamic processes of infant-caregiver social attention. It is now possible to track in much greater detail fluctuations over time with regard to object-directed attention as well as social attention and how these processes relate to one another. Encouraged by these initial results and new insights from this interactionist developmental social neuroscience approach, we conclude with a "call to action" in which we advocate for more ecologically valid paradigms for studying social attention as a dynamic and bi-directional process.

What's an early triadic interaction made of? A methodological proposal to study the musical dynamics of interaction

Classical theories of intersubjectivity hold that the first interactions in which children participate are dyadic (adult-baby). However, thanks to the material shift that is taking place in the cognitive sciences, an increasing number of authors began to recognise the constitutive role that materiality has for cognition, from the very beginning of life. Interactions do not occur in a vacuum, but within a meaning-loaded material world that adults actively seek to bring to children. While in the field of dyadic interactions studies on communicative musicality have shown how interactive exchanges are structured and how that structure unfolds over time, little is known yet about the internal structure of early triadic interactions. In this paper, we propose a longitudinal, mixed and multilevel methodological framework aimed at describing the dynamics of the musical organisation of early triadic interactions between adults, babies and things, and its development over different timescales. We conclude that if researchers want to fully understand early triadic interactions and their musical structuring, further studies that take into account the cognitive relevance of things and the dynamics of our interactions with and through materiality are needed.

Revisiting how we operationalize joint attention

Parent-child interactions support the development of a wide range of socio-cognitive abilities in young children. As infants become increasingly mobile, the nature of these interactions change from person-oriented to object-oriented, with the latter relying on children's emerging ability to engage in joint attention. Joint attention is acknowledged to be a foundational ability in early child development, broadly speaking, yet its operationalization has varied substantially over the course of several decades of developmental research devoted to its characterization. Here, we outline two broad research perspectives-social and associative accounts-on what constitutes joint attention. Differences center on the criteria for what qualifies as joint attention and regarding the hypothesized developmental mechanisms that underlie the ability. After providing a theoretical overview, we introduce a joint attention coding scheme that we have developed iteratively based on careful reading of the literature and our own data coding experiences. This coding scheme provides objective guidelines for characterizing mulitmodal parent-child interactions. The need for such guidelines is acute given the widespread use of this and other developmental measures to assess atypically developing populations. We conclude with a call for open discussion about the need for researchers to include a clear description of what qualifies as joint attention in publications pertaining to joint attention, as well as details about their coding. We provide instructions for using our coding scheme in the service of starting such a discussion.

A conceptual framework for the study of demonstrative reference

Language allows us to efficiently communicate about the things in the world around us. Seemingly simple words like this and that are a cornerstone of our capability to refer, as they contribute to guiding the attention of our addressee to the specific entity we are talking about. Such demonstratives are acquired early in life, ubiquitous in everyday talk, often closely tied to our gestural communicative abilities, and present in all spoken languages of the world. Based on a review of recent experimental work, here we introduce a new conceptual framework of demonstrative reference. In the context of this framework, we argue that several physical, psychological, and referent-intrinsic factors dynamically interact to influence whether a speaker will use one demonstrative form (e.g., this) or another (e.g., that) in a given setting. However, the relative influence of these factors themselves is argued to be a function of the cultural language setting at hand, the theory-of-mind capacities of the speaker, and the affordances of the specific context in which the speech event takes place. It is demonstrated that the framework has the potential to reconcile findings in the literature that previously seemed irreconcilable. We show that the framework may to a large extent generalize to instances of endophoric reference (e.g., anaphora) and speculate that it may also describe the specific form and kinematics a speaker's pointing gesture takes. Testable predictions and novel research questions derived from the framework are presented and discussed.

Large-scale assessment of 7-11-year-olds’ cognitive and sensorimotor function within the Born in Bradford longitudinal birth cohort study

Background: Cognitive ability and sensorimotor function are crucial aspects of children’s development, and are associated with physical and mental health outcomes and educational attainment. The current project forms part of the Born in Bradford (BiB) longitudinal birth-cohort study, and involved measuring sensorimotor and cognitive function in over 15,000 children aged 7-10 years. This paper describes the large-scale data collection process and presents initial analyses of the data, including the relationship between cognition/sensorimotor ability and age and task difficulty, and associations between tasks. Method: Data collection was completed in 86 schools between May 2016 and July 2019. Children were tested at school, individually, using a tablet computer with a digital stylus or finger touch for input. Assessments comprised a battery of three sensorimotor tasks (Tracking, Aiming, & Steering) and five cognitive tasks (three Working Memory tasks, Inhibition, and Processing Speed), which took approximately 40 minutes. Results: Performance improved with increasing age and decreasing task difficulty, for each task. Performance on all three sensorimotor tasks was correlated, as was performance on the three working memory tasks. In addition, performance on a composite working memory score correlated with performance on both inhibition and processing speed. Interestingly, within age-group variation was much larger than between age-group variation. Conclusions: The current project collected computerised measures of a range of cognitive and sensorimotor functions at 7-10 years of age in over 15,000 children. Performance varied as expected by age and task difficulty, and showed the predicted correlations between related tasks. Large within-age group variation highlights the need to consider the profile of individual children in studying cognitive and sensorimotor development. These data can be linked to the wider BiB dataset including measures of physical and mental health, biomarkers and genome-wide data, socio-demographic information, and routine data from local health and education services.

Do the Eyes Have It? A Systematic Review on the Role of Eye Gaze in Infant Language Development

Eye gaze is a ubiquitous cue in child–caregiver interactions, and infants are highly attentive to eye gaze from very early on. However, the question of why infants show gaze-sensitive behavior, and what role this sensitivity to gaze plays in their language development, is not yet well-understood. To gain a better understanding of the role of eye gaze in infants' language learning, we conducted a broad systematic review of the developmental literature for all studies that investigate the role of eye gaze in infants' language development. Across 77 peer-reviewed articles containing data from typically developing human infants (0–24 months) in the domain of language development, we identified two broad themes. The first tracked the effect of eye gaze on four developmental domains: (1) vocabulary development, (2) word–object mapping, (3) object processing, and (4) speech processing. Overall, there is considerable evidence that infants learn more about objects and are more likely to form word–object mappings in the presence of eye gaze cues, both of which are necessary for learning words. In addition, there is good evidence for longitudinal relationships between infants' gaze following abilities and later receptive and expressive vocabulary. However, many domains (e.g., speech processing) are understudied; further work is needed to decide whether gaze effects are specific to tasks, such as word–object mapping or whether they reflect a general learning enhancement mechanism. The second theme explored the reasons why eye gaze might be facilitative for learning, addressing the question of whether eye gaze is treated by infants as a specialized socio-cognitive cue. We concluded that the balance of evidence supports the idea that eye gaze facilitates infants' learning by enhancing their arousal, memory, and attentional capacities to a greater extent than other low-level attentional cues. However, as yet, there are too few studies that directly compare the effect of eye gaze cues and non-social, attentional cues for strong conclusions to be drawn. We also suggest that there might be a developmental effect, with eye gaze, over the course of the first 2 years of life, developing into a truly ostensive cue that enhances language learning across the board.

Using head-mounted eye tracking to examine visual and manual exploration during naturalistic toy play in children with and without autism spectrum disorder

Multimodal exploration of objects during toy play is important for a child's development and is suggested to be abnormal in children with autism spectrum disorder (ASD) due to either atypical attention or atypical action. However, little is known about how children with ASD coordinate their visual attention and manual actions during toy play. The current study aims to understand if and in what ways children with ASD generate exploratory behaviors to toys in natural, unconstrained contexts by utilizing head-mounted eye tracking to quantify moment-by-moment attention. We found no differences in how 24- to 48-mo children with and without ASD distribute their visual attention, generate manual action, or coordinate their visual and manual behaviors during toy play with a parent. Our findings suggest an intact ability and willingness of children with ASD to explore toys and suggest that context is important when studying child behavior.

Acting with shared intentions: A systematic review on joint action coordination in Autism Spectrum Disorder

BACKGROUND

Joint actions, described as a form of social interaction in which individuals coordinate their actions in space and time to bring about a change in the environment, rely on sensory-motor processes that play a role in the development of social skills. Two brain networks, associated with "mirroring" and "mentalizing", are engaged during these actions: the mirror neuron and the theory of mind systems. People with autism spectrum disorder (ASD) showed impairment in interpersonal coordination during joint actions. Studying joint action coordination in ASD will contribute to clarify the interplay between sensory-motor and social processes throughout development and the interactions between the brain and the behavior.

METHOD

This review focused on empirical studies that reported behavioral and kinematic findings related to joint action coordination in people with ASD.

RESULTS

Literature on mechanisms involved in the joint action coordination impairment in ASD is still limited. Data are controversial. Different key-components of joint action coordination may be impaired, such as cooperative behavior, temporal coordination, and motor planning.

CONCLUSIONS

Interpersonal coordination during joint actions relies on early sensory-motor processes that have a key role in guiding social development. Early intervention targeting the sensory-motor processes involved in the development of joint action coordination could positively support social skills.

Detection of eye contact with deep neural networks is as accurate as human experts

Eye contact is among the most primary means of social communication used by humans. Quantification of eye contact is valuable as a part of the analysis of social roles and communication skills, and for clinical screening. Estimating a subject's looking direction is a challenging task, but eye contact can be effectively captured by a wearable point-of-view camera which provides a unique viewpoint. While moments of eye contact from this viewpoint can be hand-coded, such a process tends to be laborious and subjective. In this work, we develop a deep neural network model to automatically detect eye contact in egocentric video. It is the first to achieve accuracy equivalent to that of human experts. We train a deep convolutional network using a dataset of 4,339,879 annotated images, consisting of 103 subjects with diverse demographic backgrounds. 57 subjects have a diagnosis of Autism Spectrum Disorder. The network achieves overall precision of 0.936 and recall of 0.943 on 18 validation subjects, and its performance is on par with 10 trained human coders with a mean precision 0.918 and recall 0.946. Our method will be instrumental in gaze behavior analysis by serving as a scalable, objective, and accessible tool for clinicians and researchers.

GlassesViewer: Open-source software for viewing and analyzing data from the Tobii Pro Glasses 2 eye tracker

We present GlassesViewer, open-source software for viewing and analyzing eye-tracking data of the Tobii Pro Glasses 2 head-mounted eye tracker as well as the scene and eye videos and other data streams (pupil size, gyroscope, accelerometer, and TTL input) that this headset can record. The software provides the following functionality written in MATLAB: (1) a graphical interface for navigating the study- and recording structure produced by the Tobii Glasses 2; (2) functionality to unpack, parse, and synchronize the various data and video streams comprising a Glasses 2 recording; and (3) a graphical interface for viewing the Glasses 2's gaze direction, pupil size, gyroscope and accelerometer time-series data, along with the recorded scene and eye camera videos. In this latter interface, segments of data can furthermore be labeled through user-provided event classification algorithms or by means of manual annotation. Lastly, the toolbox provides integration with the GazeCode tool by Benjamins et al. (2018), enabling a completely open-source workflow for analyzing Tobii Pro Glasses 2 recordings.