Marygrace Yale

Responding to Joint Attention Across the 6- Through 24-Month Age Period and Early Language Acquisition

Abstract This study examined individual differences in the development of the capacity of infants to respond to the joint attention bids of others (e.g., gaze shift, pointing, and vocalizing) across the first and second year. The primary aim of the study was to determine if responding to joint attention (RJA) in the first and second year was related to subsequent vocabulary acquisition and whether a specific period of development during the first 2 years was optimal for the assessment of individual differences in this skill. The study was also designed to determine if RJA provided unique predictive information about language development over and above that provided by parent reports of early vocabulary acquisition. Findings indicated that RJA at 6, 8, 10, 12, and 18 months was positively related to individual differences in vocabulary development. Furthermore, both a 6- to 18-month aggregate measure of RJA and a parent report measure of language development made unique contributions to the predictions of vocabulary acquisition. Finally, individual differences in RJA measured at 21 and 24 months were not related to language development.

Individual Differences in Infant Skills as Predictors of Child‐Caregiver Joint Attention and Language

Current research suggests that the extent to which child-caregiver dyads engage in interactions involving episodes of joint or coordinated attention can have a significant impact on early lexical acquisition. In this regard it has been recognized that individual differences in early developing child communication skills, such as capacity to follow gaze and early infant language, may contribute to these child-caregiver interactional patterns, as well as to subsequent language development. To address this expectation, 21 infant-parent dyads were recruited for participation in a longitudinal study. Early infant language, responding to joint attention skill, and cognitive development were assessed at 12 months of age. Child-caregiver joint attention episodes, as well as responding to joint attention skill and child language, were assessed at 18 months of age. Developmental outcome, using the MacArthur Communicative Development Inventories and the Bayley Scales of Infant Development-II, was assessed at 21 and 24 months of age. Consistent with previous findings, results indicated that individual differences in child-caregiver episodes of joint attention were related to language at 18 months. In addition, though, 12 month vocabulary and responding to joint attention skill were associated with some aspects of 18 month child-caregiver interaction, as well as subsequent language development. In general, 12 month child measures and 18 month child-caregiver interaction measures appeared to make unique contributions to language development in this sample. These results suggest the need to further consider the role of infant skills in the connections between child-caregiver joint attention episodes and language development.

Gaze following, temperament, and language development in 6-month-olds: A replication and extension

Abstract This study examined the age of onset of the capacity to align with direction of gaze, and the relations between individual differences in this capacity, temperament and language acquisition. Infants demonstrated the capacity to match mother’s direction of gaze, and individual differences in this capacity were related to temperament and vocabulary development.

Getting the point: electrophysiological correlates of protodeclarative pointing

We examined the longitudinal relationships between power data in two bands (i.e. 4–6 and 6–9 Hz) of electrical activity in the brain at 14 months, as measured by background electroencephalograms (EEG), with protodeclarative and protoimperative pointing at 18 months, as measured by the Early Social Communication Scales (ESCS), [Mundy et al., ESCS: A Preliminary Manual for the Abridged Early Social Communication Scales, 1996, unpublished manual] (n=27). EEGs were recorded from 64 sensors using the Electrical Geodesics (EGI) systems dense array sensor nets. Multivariate permutation testing (MPT), which controlled for experiment‐wise error due to multiple significance tests, revealed significant correlations between log‐transformed power in the frontal region at 14 months and protodeclarative, but not protoimperative, pointing at 18 months.

Infant responses to direction of parental gaze: A comparison of two still-face conditions

Abstract Six-month-old infants (N=43) showed differences in the frequency of neutral/positive vocalizations produced when exposed to a standard (parent gazes at infant) versus modified still-face condition (parent gazes above infant). No significant differences in smiling, social gaze, negative affect, and fuss/cry vocalizations were observed.

An Event-Based Analysis of the Coordination of Early Infant Vocalizations and Facial Actions.

This study used an event-based approach to provide empirical evidence regarding the nature of coordination in 3- and 6-month-old infants. Vocalizations and facial actions of 12 normally developing infants interacting with their caregivers were coded. Coded vocalizations and facial actions were considered coordinated when they temporally overlapped. Results indicate that infants coordinated their vocalizations and facial actions more than expected by chance. Coordinated events were governed by 2 sequence patterns. When 2 communicative events were temporally associated across modalities, 1 event tended to be completely embedded within the other, and vocalizations tended to end before facial actions. This study provides new information about how infant communication is structured, confirms results from other coordination studies, and describes a new method for analysis of event-based data.