Correlates of infant pointing frequency in the first year

This study examines the emergence of concurrent correlates of infant pointing frequency with the aim of contributing to its ontogenetic theories. We measured monthly from 8 to 12 months infants' (N = 56) index-finger pointing frequency along with several candidate correlates: (1) family socioeconomic status (SES), (2) mothers' pointing production, and (3) infants' point following to targets in front of and behind them. Results revealed that (1) infants increased their pointing frequency across age, but high-SES infants had a steeper increase, and a higher pointing frequency than low-SES infants from 10 months onward, (2) maternal pointing frequency was not associated with infant pointing frequency at any age, (3) infants' point following abilities to targets behind their visual fields was positively associated with their pointing frequency at 12 months, after pointing had already emerged around 10 months. Findings suggest that family SES impacts infants' pointing development more generally, not just through maternal pointing. The association between pointing and following points to targets behind, but not in front, suggests that a higher level of referential understanding emerges after, and perhaps through the production of pointing.     

Associations between observed and reported infant negative affectivity,fear and self-regulation,and early communicative development—Evidence from the FinnBrain Birth Cohort Study

Self-regulation and language are intertwined abilities, but the nature of their relations in early childhood when both skills are still emerging is insufficiently understood. Our knowledge of the relations between early negative affectivity and preverbal and verbal communicative development is still limited. Further, observed and reported temperament capture how aspects of temperament operate in different settings but are rarely used in parallel in studies examining early language. During the period of rapid development, longitudinal studies are needed to identify early risk factors for delayed communicative development. We studied relations between aspects of emerging self-regulation and negative affectivity using both observations at 8 months and mother-reports at 6 and 12 months, and communicative development measured by gesturing and vocabulary at 14 and vocabulary at 30 months in 183 children. Mother-reported self-regulation was related to a higher use of communicative gestures and observed self-regulation by gaze aversion to poorer receptive and expressive vocabulary at 14 months, but neither was significantly associated with vocabulary at 30 months. We found little evidence for associations between negative affectivity and fear in infancy and communicative development. Our findings highlight different aspects of self-regulation as both potential risk and protective factors for communicative development. Mixed results indicate a need for a more detailed examination of different strategies of self-regulation in different conditions and developmental stages to yield a deeper understanding of the relations between self-regulation in infancy and communicative development.     

Mothers' use of touch across infants' development and its implications for word learning: Evidence from Korean dyadic interactions

Caregivers' touches that occur alongside words and utterances could aid in the detection of word/utterance boundaries and the mapping of word forms to word meanings. We examined changes in caregivers' use of touches with their speech directed to infants using a multimodal cross-sectional corpus of 35 Korean mother-child dyads across three age groups of infants (8, 14, and 27 months). We tested the hypothesis that caregivers' frequency and use of touches with speech change with infants' development. Results revealed that the frequency of word/utterance-touch alignment as well as word + touch co-occurrence is highest in speech addressed to the youngest group of infants. Thus, this study provides support for the hypothesis that caregivers' use of touch during dyadic interactions is sensitive to infants' age in a way similar to caregivers' use of speech alone and could provide cues useful to infants' language learning at critical points in early development.     

Families,Not Parents,Differ: Development of Communication in Finnish Infants

This longitudinal study on Finnish families was conducted to identify developmental differences in family‐level communication among mothers, fathers, and their infants during the second half of the infant's first year, and associations with infants' later language and communicative skills. We examined coregulated communication of parent‐infant dyads during 5‐min laboratory play sessions at 7 and 11 months. Few differences in mutually regulated communicative exchanges emerged between maternal and paternal dyads, and few developmental changes were found across the whole sample. Families with different communication profiles were identified, and changes rather than stability characterized communicative development at the family level. The family‐level differences at 7 months predicted variation in children's language and communicative skills at 14 months.     

Infants’ Lexical Processing Efficiency is Related to Vocabulary Size by One Year of Age

By 15–18 months, infants’ skill in interpreting familiar words, or lexical processing efficiency (LPE), improves substantially and is correlated with vocabulary size concurrently and several months later. Prior to this age LPE is quite poor, and to date there is little evidence that it is related to vocabulary size. If this relation only emerges once infants have relatively good LPE, and also know a substantial number of words, it could suggest that the processes that support the rapid growth in vocabulary commonly observed as infants approach age 2 may not yet be functional in the earlier stages of lexical development. However, using a modified LPE task we found that 12‐month‐olds with better LPE understood more words at that age and also produced more words several months later. These results suggest that meaningful individual differences in LPE are already emerging by 12 months and may support lexical development across the second year.     

Separable Attentional Predictors of Language Outcome

The aim of this study was to examine the combined influences of infants' attention and use of social cues in the prediction of their language outcomes. This longitudinal study measured infants' visual attention on a distractibility task (11 months), joint attention (14 months), and language outcomes (word–object association, 14 months; MBCDI vocabulary size and multi‐word productions at 18 months of age). Path analyses were conducted for two different language outcomes. The analysis for vocabulary revealed unique direct prediction from infants' visual attention on a distractibility task (i.e., maintaining attention to a target event in the presence of competing events) and joint attention (i.e., more frequent response to tester's bids for attention) for larger vocabulary size at outcome; this model accounted for 48% of variance in vocabulary, after controlling for baseline communication status (assessed at 11 months). The analysis for multi‐word productions yielded direct effects for infants' distractibility, but not joint attention; this model accounted for 45% of variance in multi‐word productions, again after controlling for baseline communication status. Indirect effects were not significant in either model. Results are discussed in light of the unique predictive role of attentional factors and social/attention cues for emerging language.     

Can a Click be a Word?: Infants' Learning of Non‐Native Words

Forms that are nonlinguistic markers in one language (i.e., “tsk‐tsk” in English) may be part of the phoneme inventory—and hence part of words—in another language. In the current paper, we demonstrate that infants' ability to learn words containing unfamiliar language sounds is influenced by the age and vocabulary size of the infant learner, as well as by cues to the speaker's referential intent. When referential cues were available, infants at 14 months learned words with non‐native speech sounds, but at 20 months only those infants with smaller vocabularies succeeded. When no referential cues were present, infants at both 14 and 20 months failed to learn the same words. The implications of the relation between linguistic sophistication and non‐native word learning are discussed.     

A parent gesture intervention as a means to increase parent declarative pointing and child vocabulary

This study examined whether a brief parent gesture training resulted in a change in the communicative intent of pointing gestures used by parents of infants from age 10–12 months and whether specific types of points (declarative vs. imperative) were more or less likely to predict later child language skill at 18 months. Compared to parents who were randomized to the control group, parents in the intervention group produced significantly more declarative pointing gestures as a result of the intervention. Moreover, parents’ use of declarative points at 12 months was predictive of later child vocabulary comprehension at 18 months. These findings suggest that a short-term parent training can have important effects on the communicative intentions conveyed through gesture which predict vocabulary development.     

What's the point? Infants' and adults' perception of different pointing gestures

Adults and infants as young as 4 months old orient to pointing gestures. Although adults are shown to orient faster to index-finger pointing than other hand shapes, it is unknown whether hand shapes influence infants' perception of pointing. In this study, we used a spatial cueing paradigm on an eye tracker to investigate whether and to what extent adults and 12-month-old infants orient their attention in the direction of pointing gestures with different hand shapes: index finger, whole hand, and pinky finger. Furthermore, we assessed infants' and their parents' pointing production. Results revealed that adults showed a reliable cueing effect: shorter saccadic reaction times (SRTs) to congruent than incongruent targets, for all hand shapes. However, they did not show a larger cueing effect triggered by the index or any other finger. This contradicts previous findings and is discussed with respect to the differences in methodology. Infants showed a cueing effect only for the whole hand but not for the index or pinky fingers. The current results suggest that infants' orienting to pointing may be more robust for the whole hand shape in the first year, and tuning in to the social-communicative relevance of the canonical index finger shape may develop later or require additional social-communicative cues.     

The Value of Vocalizing: 10‐Month‐Olds' Vocal Usage Relates to Language Outcomes at 15 Months

The interaction between infant's communicative competence and responsiveness of caregivers facilitates the transition from prelinguistic to linguistic communication. It is thus important to know how infants' communicative behavior changes in relation to different caregiver responses; furthermore, how infants' modification of communicative behavior relates to language outcomes. We investigated 39 10‐month‐old infants' communication as a function of mothers' attention and responses and the relationship to language outcomes at 15 months. We elicited infants' communicative behavior in three conditions: (1) joint attention: Mothers were visually attending and responding to infants' attention and interest; (2) available: Mothers were visually attending to infants, but not responding contingently to infants' attention and interest; (3) unavailable: Mothers were not attending to infants nor responding to them. Infants vocalized more when mothers attended and responded to them (conditions 1 and 2) than when mothers did not (condition 3), but infants' gesture and gesture‐vocal production did not differ across conditions. Furthermore, infants' production of a higher proportion of vocalizations in the unavailable condition relative to the joint attention condition correlated with, and predicted, infants' language scores at 15 months. Thus, infants who appear to be aware of the social effects of vocalizations may learn words better.     

Parental Speech at 6 Months Predicts Joint Attention at 12 Months

In a prospective longitudinal study of a representative community sample (N = 264), mothers' references to infants' mental states were coded during a topic‐sharing task in the home at 6 months. Joint attention behaviour was assessed in the laboratory at 12 months. Individual joint attention skills (gaze following, gaze alternating, and declarative pointing) were significantly inter‐correlated, with a single factor accounting for 68% of the variance. Mothers' references to infants' mental states at 6 months predicted infants' joint attention at 12 months. The association was not explained by sociodemographic characteristics of the family, the mother's mental state, or by the quantity or acoustic properties of her speech. However, variability in pitch of maternal speech was an independent predictor of the infants' later joint attention skills. Taken together, these findings suggest that mothers' infant‐directed speech fosters infants' attentive participation in topic‐sharing interactions, which in turn provide an important arena in which joint attention skills develop over the first year of life.     

The context of infants' giving gestures in mother-infant dyads: Typical giving gestures and those contingent on exploration and play

This study aimed to focus on a niche that has not yet been investigated in infants' gesture studies that is the effect of the prior context of one specific gestural behavior (gives) on maternal behavior. For this purpose, we recruited 23 infants at 11 and 13 months of age yielded 246 giving gesture bouts that were performed in three contexts: typical when the object was offered immediately, contingent on exploration, and contingent on play. The analysis revealed that maternal responses to infants' giving gestures varied and were affected by their age and gesture context. Hence, mothers amended their responses according to the background that generated each gesture. The number of verbal responses to infants' giving gestures decreased as the infants aged, whereas the number of pretense responses increased. For infants aged 11 months, mothers generally provided motor responses to typical gestures. However, for infants aged 13 months, this trend declined and was replaced by a strong positive correlation between giving gestures contingent on play and verbal responses. We concluded that the type of activity with objects prior to employing giving gestures could enhance infants' symbolic skills because caregivers monitor the contingent act that yields the gesture that shapes their response.     

Maternal Responsiveness and the Development of Directed Vocalizing in Social Interactions

For effective communication, infants must develop the phonology of sounds and the ability to use vocalizations in social interactions. Few studies have examined the development of the pragmatic use of prelinguistic vocalizations, possibly because gestures are considered hallmarks of early pragmatic skill. The current study investigated infant vocal production and maternal responsiveness to examine the relationship between infant and maternal behavior in the development of infants' vocal communication. Specifically, we asked whether maternal responses to vocalizations could influence the development of prelinguistic vocal usage, as has been documented in recent experimental studies exploring the relation between maternal responses and phonological development. Twelve mother–infant dyads participated over a six‐month period (between 8 and 14 months of age). Mothers completed the MacArthur Communicative Development Inventory when infants were 15 months old. Maternal sensitive responses to infant vocalizations in the previous months predicted infants' mother‐directed vocalizations in the following months, rather than overall response rate. Furthermore, mothers' sensitive responding to mother‐directed vocalizations was correlated with an increase in developmentally advanced, consonant–vowel vocalizations and some language measures. This is the first study to document a social shaping mechanism influencing developmental change in pragmatic usage of vocalizations in addition to identifying the specific behaviors underlying development.     

Infants' Ability to Distinguish Between Intentional and Accidental Actions and Its Relation to Internal State Language

The experiment reported here investigated infants' concept of intention, as well as the relation among intention understanding, general productive vocabulary, and internal state language production during the 2nd year. Results from an imitation task indicated that 18‐month‐olds are better able to differentiate between intentional and accidental actions than 14‐month‐olds. Although there was no relation between infants' performance on the intention task and their general productive vocabulary, internal state language production at 30 months was predicted by infants' ability to differentiate between intentional and accidental actions about a year earlier. These findings shed light on the developmental progression of infants' concept of intention, as well as on the continuity between infants' understanding of intentional action and their ability to use internal state words.     

The Relationship Between Infant Holdout and Gives,and Pointing

We provide an analysis of holdout and giving (Ho&G) behaviours in prelinguistic infants and investigate their relationship with index finger pointing. The frequency of Ho&Gs at 10 and 11 months along with the length of the following social interaction correlated with index finger pointing at 12 months. We conclude that Ho&Gs are a precursor to index finger pointing and that this provides support for social‐pragmatic approaches to communicative development.     

Mother-infant emotional availability through the COVID-19 pandemic: Examining continuity,stability, and bidirectional associations

The COVID-19 pandemic may impact the development of infants' social communication patterns with their caregivers. The current study examined continuity, stability, and bidirectional associations in maternal and infant dyadic Emotional Availability (EA) before and during the COVID-19 pandemic. Participants were 110 Israeli mother-infant dyads (51% girls) that were assessed prior to (Mage = 3.5 months) and during (Mage = 12.4 months) the pandemic. At both time points, mother-infant interactions were observed during play (nonstressful context) and tasks designed to elicit infant frustration (stressful context). Maternal and child EA were coded offline. Maternal EA demonstrated no significant mean-level changes from before to during the COVID-19 pandemic, whereas infant responsiveness and involvement increased over time. Stability and bidirectional associations in EA differed by context and were evident only in the stressful context. Mothers' perceived levels of social support further moderated these associations. Specifically, infants' pre-pandemic responsiveness and involvement predicted maternal EA during the pandemic only when mothers reported low levels of social support. Our findings suggest that maternal and child EA were not adversely impacted by the COVID-19 pandemic. However, patterns of EA demonstrated moderate-to-no stability over time, suggesting considerable individual differences in trajectories of EA.     

Infants' Perception of Intonation: Is It a Statement or a Question?

The ability to distinguish phonetic variations in speech that are relevant to meaning is essential for infants' language development. Previous studies into the acquisition of prosodic categories have focused on lexical stress, lexical pitch accent, or lexical tone. However, very little is known about the developmental course of infants' perception of linguistic intonation. In this study, we investigate infants' perception of the correlates of the statement/yes–no question contrast in a language that marks this sentence type distinction only by prosodic means, European Portuguese (EP). Using a modified version of the visual habituation paradigm, EP‐learning infants at 5–6 and 8–9 months were able to successfully discriminate segmentally varied, single‐prosodic word intonational phrases presented with statement or yes–no question intonation, demonstrating that they are sensitive to the prosodic cues marking this distinction as early as 5 months and maintain this sensitivity throughout the first year. These results suggest the presence of precocious discrimination abilities for intonation across segmental variation, similarly to previous reports for lexical pitch accent, but unlike previous findings for word stress.     

The Ability to Map Differentially Stressed Labels to Objects Predicts Language Development at 24 months in 12‐month‐olds at High Risk for Autism

Sensitivity to language‐specific stress patterns during infancy facilitates finding, mapping, and recognizing words, and early preferences for the predominate stress pattern of the infant's native language have been argued to facilitate language relevant outcomes (Ference & Curtin, 2013 Journal of Experimental Child Psychology, 116, 891; Weber et al., 2005 Cognitive Brain Research, 25, 180). We examined 12‐month‐old infant siblings of typically developing children (SIBS‐TD) and infant siblings of children diagnosed with autism spectrum disorder (ASD; SIBS‐A) on their ability to map differentially stressed labels to objects. We also examined whether success at this task relates to infants’ vocabulary size at 12 months, and more specifically to SIBS‐A's vocabulary at both 12 and 24 months. SIBS‐TD successfully mapped the word–object pairings, which related to their vocabulary comprehension at 12 months. In contrast, SIBS‐A as a group did not map the word–object pairings, which was unrelated to vocabulary size at 12 months. However, success on this task for SIBS‐A predicted expressive language abilities at 24 months using the Mullen Scales of Early Learning (MSEL; Mullen, 1995 Mullen Scales of Early Learning. Circle Pines, MN: American Guidance) and the MacArthur‐Bates Communicative Development Inventory (MB‐CDI; Fenson et al., 1993 MacArthur Communicative Development Inventory: Users Guide and Technical Manual. San Diego, CA: Singular Publishing Company). Our study is the first to demonstrate that 12‐month‐old SIBS‐A who succeed at word mapping using lexical stress are more likely to have stronger expressive language abilities at 24 months.     

Mothers' Verbal and Nonverbal Strategies in Relation to Infants' Object‐Directed Actions in Real Time and Across the First Three Years in Ethnically Diverse Families

We examined maternal behavioral strategies in relation to infants' object‐directed actions in real time and over developmental time in 206 mother–infant dyads from African American, Dominican immigrant, and Mexican immigrant backgrounds. Mothers were asked to share a set of beads and strings with their infants when children were 14, 24, and 36 months. We coded three types of maternal strategies—eliciting attention, instructive assistance, and encouragement—which could be expressed verbally (e.g., “look”, “turn it”, “good job!”) or physically (i.e., through gestures, hands‐on guidance, or transfer of objects). We also coded infants' unassisted bead‐stringing. Across ethnic groups and ages, mothers' hands‐on guidance and object transfer increased the likelihood that infants would follow with unassisted bead‐stringing during real‐time interaction. Over developmental time, mothers modified their strategies: They displayed fewer attention‐getting strategies and more encouragement across infant ages, and peaked in their provision of instructive assistance when infants were 24 months. Additionally, Mexican mothers displayed more nonverbal strategies (e.g., gestures, hands‐on guidance) than did African American and/or Dominican mothers, who displayed more verbal strategies (e.g., attention‐getting and encouraging language). Developmental and real‐time patterns in mother–infant object‐related interactions generalize across ethnicities, although mothers' emphases on specific strategies are culture specific.     

Effects of Maternal Responsiveness on Infant Responsiveness and Behavior in the Still‐Face Task

The effects of maternal responsiveness on infant responsiveness and behavior in the Still‐Face Task were longitudinally examined through infants' first 3 months. Maternal vocal responsiveness and infant vocal and smiling responsiveness significantly increased when infants were 2 months of age. Mothers showed continuity of individual differences in vocal responsiveness from the infants' newborn period. Maternal responsiveness predicted infant responsiveness within and across sessions. Compared with infants with low‐responsive mothers, infants with high‐responsive mothers were more attentive and affectively engaged during the Still‐Face Task from 1 month of age. Infants with high‐responsive mothers discriminated between the task phases with their smiling at 1 month, a month before infants with low‐responsive mothers did so. Infants in both groups discriminated between the phases with their attention and nondistress vocalizations throughout their first 3 months. Results suggest that maternal responsiveness influences infant responsiveness and facilitates infants' engagement and expectations for social interaction.