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.

Temperament in Toddlers With and Without Prelingual Hearing Loss.

PURPOSE: The purpose of this study is to examine parent-reported ratings of temperament in toddlers with and without prelingual hearing loss. METHOD: The parent-completed Early Childhood Behavior Questionnaire (ECBQ) was used to assess temperament in toddlers aged 18-36 months. Three dimensions of temperament were examined: surgency, negative affectivity, and effortful control. Analyses were conducted to (a) examine differences in temperament across toddlers with and without prelingual hearing loss; (b) examine possible associations between temperament, demographic, and communication factors; and (c) determine if the ECBQ is sensitive to differences in hearing, communication, and listening skills among toddlers with prelingual hearing loss. RESULTS: The parent-completed ECBQ revealed that toddlers with prelingual hearing loss differed from their hearing peers on some but not all dimensions of temperament. Specifically, children with prelingual hearing loss were rated as displaying higher levels of surgency and lower levels of effortful control but comparable levels of negative affectivity when compared to their hearing peers. Regression analyses revealed that chronological age and communication strategy predicted scores of effortful control in toddlers with prelingual hearing loss, whereas chronological age alone predicted scores of effortful control in toddlers with hearing. Finally, the ECBQ appears to contain "listening" items that skew (lower) levels of effortful control in toddlers with prelingual hearing loss, such that only the group effect of higher levels of surgency remained after removing these "listening" items. Correlations between the original and our modified ECBQ (removing the "listening" items) revealed strong associations, reflective of high construct validity. CONCLUSIONS: This was the first study to measure temperament in toddlers with prelingual hearing loss using the ECBQ. Our results revealed differences between children with and without prelingual hearing loss centering on the dimension of surgency. Examining differences in temperament during the toddler period of development may be particularly important and useful for predicting functional outcomes following prelingual hearing loss.

Are prosodic effects on sentence comprehension dependent on age?

PURPOSE: to investigate prosodic boundary effects on the comprehension of attachment ambiguities in Brazilian Portuguese and to test two hypotheses relying on the notion of boundary strength: the absolute boundary hypothesis (ABH) and the relative boundary hypothesis (RBH). Manipulations of prosodic structure influence how listeners interpret syntactically ambiguous sentences. However, the role of prosody in spoken language comprehension of sentences has received limited attention in languages other than English, particularly from a developmental perspective. METHODS: Twenty-three adults and 15 children participated in a computerized sentence comprehension task involving syntactically ambiguous sentences. Each sentence was recorded in eight different prosodic forms with acoustic manipulations of F0, duration and pause varying the boundary size to reflect predictions of the ABH and RBH. RESULTS: Children and adults differed in how prosody influenced their syntactic processing and children were significantly slower than adults. Results indicated that interpretation of sentences varied according to their prosodic forms. CONCLUSION: Neither the ABH or the RBH explained how children and adults who speak Brazilian Portuguese use prosodic boundaries to disambiguate sentences. There is evidence that the way prosodic boundaries influence disambiguation varies cross-linguistically.

The effect of sentence length on question comprehension in children with cochlear implants.

OBJECTIVES: The present study investigated the comprehension of subject and object who and which questions in children with cochlear implants (CI). METHODS: Growth Curve Analysis (GCA) was used to compare eye gaze fixations and gaze patterns to the appropriate subject or object nouns within a four-picture array between 16 children with CI and 31 children with typical hearing (aged 7;0-12;0) on wh-questions with and without added adjectives to increase length. Offline accuracy was also compared. RESULTS: Findings indicated children with typical hearing exhibited more fixations to the target noun across all conditions, supporting higher comprehension accuracy. Both groups of children demonstrated more fixations to the target noun in object questions and questions without added length. Patterns of eye movement were significantly different between groups, suggesting different patterns of eye gaze across the array before fixation on the target noun. Children with CI exhibited fewer fixations, slower speed to fixation, and differences in gaze patterns that may imply the presence of processing limitations. Error analyses also suggested that children with CI frequently fixated on a picture similar to the target noun. CONCLUSIONS: Results indicate children with CI comprehend questions more slowly than their hearing peers, which may be related to limitations in working memory.

Barriers to and Facilitators of Early Hearing Detection and Intervention in the United States: A Systematic Review.

OBJECTIVES: Early hearing detection and intervention (EHDI) is guided by the 1-3-6 approach: screening by one month, diagnosis by 3 mo, and early intervention (EI) enrollment by 6 mo. Although screening rates remain high, successful diagnosis and EI-enrollment lag in comparison. The aim of this systematic review is to critically examine and synthesize the barriers to and facilitators of EHDI that exist for families, as they navigate the journey of congenital hearing loss diagnosis and management in the United States. Understanding barriers across each and all stages is necessary for EHDI stakeholders to develop and test novel approaches which will effectively reduce barriers to early hearing healthcare. DESIGN: A systematic literature search was completed in May and August 2021 for empirical articles focusing on screening, diagnosis, and EI of children with hearing loss. Two independent reviewers completed title and abstract screening, full-text review, data extraction, and quality assessments with a third independent reviewer establishing consensus at each stage. Data synthesis was completed using the Framework Analysis approach to categorize articles into EHDI journey timepoints and individual/family-level factors versus system-level factors. RESULTS: Sixty-two studies were included in the narrative synthesis. Results revealed that both individual/family-level (e.g., economic stability, medical status of the infant including middle ear involvement) and system-level barriers (e.g., system-service capacity, provider knowledge, and program quality) hinder timely diagnosis and EI for congenital hearing loss. Specific social determinants of health were noted as barriers to effective EHDI; however, system-level facilitators such as care coordination, colocation of services, and family support programs have been shown to mitigate the negative impact of those sociodemographic factors. CONCLUSIONS: Many barriers exist for families to obtain appropriate and timely EHDI for their children, but system-level changes could facilitate the process and contribute to long-term outcomes improvement. Limitations of this study include limited generalizability due to the heterogeneity of EHDI programs and an inability to ascertain factor interactions.

Are prosodic effects on sentence comprehension dependent on age? / Os efeitos prosódicos na compreensão de frases variam de acordo com a idade?

ABSTRACT Purpose to investigate prosodic boundary effects on the comprehension of attachment ambiguities in Brazilian Portuguese and to test two hypotheses relying on the notion of boundary strength: the absolute boundary hypothesis (ABH) and the relative boundary hypothesis (RBH). Manipulations of prosodic structure influence how listeners interpret syntactically ambiguous sentences. However, the role of prosody in spoken language comprehension of sentences has received limited attention in languages other than English, particularly from a developmental perspective. Methods Twenty-three adults and 15 children participated in a computerized sentence comprehension task involving syntactically ambiguous sentences. Each sentence was recorded in eight different prosodic forms with acoustic manipulations of F0, duration and pause varying the boundary size to reflect predictions of the ABH and RBH. Results Children and adults differed in how prosody influenced their syntactic processing and children were significantly slower than adults. Results indicated that interpretation of sentences varied according to their prosodic forms. Conclusion Neither the ABH or the RBH explained how children and adults who speak Brazilian Portuguese use prosodic boundaries to disambiguate sentences. There is evidence that the way prosodic boundaries influence disambiguation varies cross-linguistically.

RESUMO Objetivo investigar os efeitos de fronteiras prosódicas na compreensão de ambiguidades sintáticas no português brasileiro além de testar duas hipóteses baseadas na noção de intensidade de fronteira: a hipótese de fronteira absoluta (ABH) e a hipótese de fronteira relativa (RBH). Manipulações da estrutura prosódica influenciam como os ouvintes interpretam frases sintaticamente ambíguas. No entanto, o papel da prosódia na compreensão da linguagem oral tem recebido atenção limitada em línguas além do inglês, particularmente do ponto de vista do desenvolvimento. Método Vinte e três adultos e 15 crianças participaram de uma tarefa computadorizada de compreensão de frases envolvendo frases sintaticamente ambíguas. Cada frase foi gravada em oito formas prosódicas diferentes com manipulações acústicas de F0, duração, e pausa, variando o tamanho da fronteira prosódica de modo a transparecer as previsões da ABH e RBH. Resultados Crianças e adultos diferiram em como a prosódia influenciou o processamento sintático; as crianças foram significativamente mais lentas que os adultos. Os resultados indicaram que a interpretação das frases variou de acordo com suas formas prosódicas. Conclusão Nenhuma das hipóteses (ABH ou RBH) explica como crianças e adultos falantes do Português brasileiro utilizam as fronteiras prosódicas para desambiguar frases. Há evidências de que a maneira com a qual os limites prosódicos influenciam a desambiguação de frases varia entre os idiomas.

Interactive Effects of Temperament and Family-Related Environmental Confusion on Spoken Language in Children Who Are Deaf and Hard of Hearing.

PURPOSE: The aim of this study was to examine the influence of caregivers' reports of family-related environmental confusion-which refers to the level of overstimulation in the family home environment due to auditory and nonauditory (i.e., visual and cognitive) noise-on the relation between child temperament and spoken language outcomes in children who are deaf and hard of hearing (DHH) in comparison to age-matched children with typical hearing (TH). METHOD: Two groups of families with children between 3 and 7 years of age (TH = 59, DHH = 58) were sequentially recruited from a larger longitudinal study on developmental outcomes in children who are DHH. Caregivers (all TH) completed questionnaires measuring three dimensions of child temperament (i.e., effortful control, negative affectivity, and surgency-extraversion) and family-related environmental confusion. A norm-referenced language measure was administered to children. Testing took place within the families' homes. RESULTS: For children who are DHH, effortful control was positively related to spoken language outcomes, but only when levels of family-related environmental confusion were low to moderate. Family-related environmental confusion did not interact with temperament to influence spoken language in children with TH. CONCLUSIONS: Homes with low-to-moderate levels of environmental confusion provide an environment that supports DHH children with better effortful control to harness their self-regulatory skills to achieve better spoken language comprehension than those with lower levels of effortful control. These findings suggest that efforts to minimize chaos and auditory noise in the home create an environment in which DHH children can utilize their self-regulatory skills to achieve optimal spoken language outcomes.

A Framework for Understanding the Relation Between Spoken Language Input and Outcomes for Children with Cochlear Implants.

Spoken language outcomes after cochlear implantation are highly variable. Some variance can be attributed to individual characteristics. Research with typically hearing children suggests that the amount of language directed to children may also play a role. However, several moderating factors may complicate the association between language input and language outcomes in children with cochlear implants. In this article, I present a conceptual framework that posits that the association between total language input directed to children and language outcomes is moderated by factors that influence what is accessible, attended to, and coordinated with the child. The framework also posits that children with cochlear implants exhibit more variability on those moderating factors, which explains why the relation between language input and language outcomes may be more complex even if language input is more important for successful language outcomes in this population.

Visual statistical learning in deaf and hearing infants and toddlers.

Congenital hearing loss offers a unique opportunity to examine the role of sound in cognitive, social, and linguistic development. Children with hearing loss demonstrate atypical performance across a range of general cognitive skills. For instance, research has shown that deaf school-age children underperform on visual statistical learning (VSL) tasks. However, the evidence for these deficits has been challenged, with mixed findings emerging in recent years. Here, we used a novel approach to examine VSL in the action domain early in development. We compared learning between deaf and hearing infants, prior to cochlear implantation (pre-CI), and a group of toddlers post implantation (post-CI). Findings revealed a significant difference between deaf and hearing infants pre-CI, with evidence for learning only in the hearing infants. However, there were no significant group differences between deaf and hearing toddlers post-CI, with both groups demonstrating learning. Further, VSL performance was positively correlated with language scores for the deaf toddlers, adding to the body of evidence suggesting that statistical learning is associated with language abilities. We discuss these findings in the context of previous evidence for group differences in VSL skills, and the role that auditory experiences play in infant cognitive development.

Variability in Quantity and Quality of Early Linguistic Experience in Children With Cochlear Implants: Evidence from Analysis of Natural Auditory Environments.

OBJECTIVES: Understanding how quantity and quality of language input vary across children with cochlear implants (CIs) is important for explaining sources of large individual differences in language outcomes of this at-risk pediatric population. Studies have mostly focused either on intervention-related, device-related, and/or patient-related factors, or relied on data from parental reports and laboratory-based speech corpus to unravel factors explaining individual differences in language outcomes among children with CIs. However, little is known about the extent to which children with CIs differ in quantity and quality of language input they experience in their natural linguistic environments. To address this knowledge gap, the present study analyzed the quantity and quality of language input to early-implanted children (age of implantation <23 mo) during the first year after implantation. DESIGN: Day-long Language ENvironment Analysis (LENA) recordings, derived from home environments of 14 early-implanted children, were analyzed to estimate numbers of words per day, type-token ratio (TTR), and mean length of utterance in morphemes (MLUm) in adults' speech. Properties of language input were analyzed across these three dimensions to examine how input in home environments varied across children with CIs in quantity, defined as number of words, and quality, defined as whether speech was child-directed or overheard. RESULTS: Our per-day estimates demonstrated that children with CIs were highly variable in the number of total words (mean ± SD = 25,134 ± 9,267 words) and high-quality child-directed words (mean ± SD = 10,817 ± 7,187 words) they experienced in a day in their home environments during the first year after implantation. The results also showed that the patterns of variability across children in quantity and quality of language input changes depending on whether the speech was child-directed or overheard. Children also experienced highly different environments in terms of lexical diversity (as measured by TTR) and morphosyntactic complexity (as measured by MLUm) of language input. The results demonstrated that children with CIs varied substantially in the quantity and quality of language input experienced in their home environments. More importantly, individual children experienced highly variable amounts of high-quality, child-directed speech, which may drive variability in language outcomes across children with CIs. CONCLUSIONS: Analyzing early language input in natural, linguistic environments of children with CIs showed that the quantity and quality of early linguistic input vary substantially across individual children with CIs. This substantial individual variability suggests that the quantity and quality of early linguistic input are potential sources of individual differences in outcomes of children with CIs and warrant further investigation to determine the effects of this variability on outcomes.

A phylogenomic perspective on the evolutionary history of the stonefly genus Suwallia (Plecoptera: Chloroperlidae) revealed by ultraconserved genomic elements.

Evolutionary biologists have long sought to disentangle phylogenetic relationships among taxa spanning the tree of life, an increasingly important task as anthropogenic influences accelerate population declines and species extinctions, particularly in insects. Phylogenetic analyses are commonly used to identify unique evolutionary lineages, to clarify taxonomic designations of the focal taxa, and to inform conservation decisions. Advances in DNA sequencing techniques have increasingly facilitated the ability of researchers to apply genomic methods to phylogenetic analyses, even for non-model organisms. Stoneflies are non-model insects that are important bioindicators of the quality of freshwater habitats and landscape disturbance as they spend the immature stages of their life cycles in fresh water, and the adult stages in terrestrial environments. Phylogenetic relationships within the stonefly genus Suwallia (Insecta: Plecoptera: Chloroperlidae) are poorly understood, and have never been assessed using molecular data. We used DNA sequence data from genome-wide ultraconserved element loci to generate the first molecular phylogeny for the group and assess its monophyly. We found that Palearctic and Nearctic Suwallia do not form reciprocally monophyletic clades, and that a biogeographic history including dispersal, vicariance, and founder event speciation via jump dispersal best explains the geographic distribution of this group. Our results also strongly suggest that Neaviperla forcipata (Neave, 1929) is nested within Suwallia, and the concept of the genus Suwallia should be revised to include it. Thus, we formally propose a new taxonomic combination wherein Neaviperla forcipata (Neave, 1929) is reclassified as Suwallia forcipata (Neave, 1929). Moreover, some Suwallia species (e.g., S. amoenacolens, S. kerzhneri, S. marginata, S. pallidula, and S. starki) exhibit pronounced cryptic diversity that is worthy of further investigation. These findings provide a first glimpse into the evolutionary history of Suwallia, improve our understanding of stonefly diversity in the tribe Suwallini, and highlight areas where additional research is needed.

Home Auditory Environments of Children With Cochlear Implants and Children With Normal Hearing.

OBJECTIVES: Early home auditory environment plays an important role in children's spoken language development and overall well-being. This study explored differences in the home auditory environment experienced by children with cochlear implants (CIs) relative to children with normal hearing (NH). DESIGN: Measures of the child's home auditory environment, including adult word count (AWC), conversational turns (CTs), child vocalizations (CVs), television and media (TVN), overlapping sound (OLN), and noise (NON), were gathered using the Language Environment Analysis System. The study included 16 children with CIs (M = 22.06 mo) and 25 children with NH (M = 18.71 mo). Families contributed 1 to 3 daylong recordings quarterly over the course of approximately 1 year. Additional parent and infant characteristics including maternal education, amount of residual hearing, and age at activation were also collected. RESULTS: The results showed that whereas CTs and CVs increased with child age for children with NH, they did not change as a function of age for children with CIs; NON was significantly higher for the NH group. No significant group differences were found for the measures of AWC, TVN, or OLN. Moreover, measures of CTs, CVs, TVN, and NON from children with CIs were associated with demographic and child factors, including maternal education, age at CI activation, and amount of residual hearing. CONCLUSIONS: These findings suggest that there are similarities and differences in the home auditory environment experienced by children with CIs and children with NH. These findings have implications for early intervention programs to promote spoken language development for children with CIs.

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.

Differential effects of nematode infection on pollinating and non-pollinating fig wasps: Can shared antagonism provide net benefits to a mutualism?

Species pairs that form mutualistic associations are also components of broader organismal community networks. These interaction networks have shaped the evolution of individual mutualisms through interspecific interactions ranging from secondarily mutualistic to intensely antagonistic. Our understanding of this complex context remains limited because characterizing the impacts of species interacting with focal mutualists is often difficult. How is the fitness of mutualists impacted by the co-occurring interactive network of community associates? We investigated this context using a model interaction network comprised of a fig and fig wasp mutualist, eight non-pollinating fig wasp (NPFW) antagonists/commensals and a nematode previously believed to be associated only with the pollinator wasp mutualist. Through repeated sampling and field observations, we characterized the ecological roles of these mutualist-associated organisms to identify key antagonists. We then investigated how potential nematode infection of NPFWs could impact wasp survival across key life stages and, in turn, inferred how this influences the fitness of the fig-pollinator mutualists. Unexpectedly, we found all Ficus petiolaris-associated NPFWs to be the targets for nematode infection, with infection levels sometimes exceeding that of pollinators. Experimental data collected for the most abundant NPFW species suggest that nematode infection significantly reduces their longevity. Further, comparisons of nematode loads for emerging and successfully arriving NPFWs suggest that infection severely limits their dispersal ability. Through these observations, we conclude that this infection could impact NPFWs more severely than either mutualistic partner, suggesting a novel role of density-dependent facultative mutualism between figs, pollinator wasps and the nematode. This antagonist-mediated suppression of other network antagonists may present an ecologically common mechanism through which antagonists can present net benefits for mutualists' fitness.

Estimating the reduced benefit of infant-directed speech in cochlear implant-related speech processing.

Caregivers modify their speech when talking to infants, a specific type of speech known as infant-directed speech (IDS). This speaking style facilitates language learning compared to adult-directed speech (ADS) in infants with normal hearing (NH). While infants with NH and those with cochlear implants (CIs) prefer listening to IDS over ADS, it is yet unknown how CI processing may affect the acoustic distinctiveness between ADS and IDS, as well as the degree of intelligibility of these. This study analyzed speech of seven female adult talkers to model the effects of simulated CI processing on (1) acoustic distinctiveness between ADS and IDS, (2) estimates of intelligibility of caregivers' speech in ADS and IDS, and (3) individual differences in caregivers' ADS-to-IDS modification and estimated speech intelligibility. Results suggest that CI processing is substantially detrimental to the acoustic distinctiveness between ADS and IDS, as well as to the intelligibility benefit derived from ADS-to-IDS modifications. Moreover, the observed variability across individual talkers in acoustic implementation of ADS-to-IDS modification and the estimated speech intelligibility was significantly reduced due to CI processing. The findings are discussed in the context of the link between IDS and language learning in infants with CIs.

Circumspection in using automated measures: Talker gender and addressee affect error rates for adult speech detection in the Language ENvironment Analysis (LENA) system.

Automatic speech processing devices have become popular for quantifying amounts of ambient language input to children in their home environments. We assessed error rates for language input estimates for the Language ENvironment Analysis (LENA) audio processing system, asking whether error rates differed as a function of adult talkers' gender and whether they were speaking to children or adults. Audio was sampled from within LENA recordings from 23 families with children aged 4-34 months. Human coders identified vocalizations by adults and children, counted intelligible words, and determined whether adults' speech was addressed to children or adults. LENA's classification accuracy was assessed by parceling audio into 100-ms frames and comparing, for each frame, human and LENA classifications. LENA correctly classified adult speech 67% of the time across families (average false negative rate: 33%). LENA's adult word count showed a mean +47% error relative to human counts. Classification and Adult Word Count error rates were significantly affected by talkers' gender and whether speech was addressed to a child or an adult. The largest systematic errors occurred when adult females addressed children. Results show LENA's classifications and Adult Word Count entailed random - and sometimes large - errors across recordings, as well as systematic errors as a function of talker gender and addressee. Due to systematic and sometimes high error in estimates of amount of adult language input, relying on this metric alone may lead to invalid clinical and/or research conclusions. Further validation studies and circumspect usage of LENA are warranted.

Action prediction during real-time parent-infant interactions.

Social interactions provide a crucial context for early learning and cognitive development during infancy. Action prediction-the ability to anticipate an observed action-facilitates successful, coordinated interaction and is an important social-cognitive skill in early development. However, current knowledge about infant action prediction comes largely from screen-based laboratory tasks. We know little about what infants' action prediction skills look like during real-time, free-flowing interactions with a social partner. In the current study, we used head-mounted eyetracking to quantify 9-month-old infants' visual anticipations of their parents' actions during free-flowing parent-child play. Our findings reveal that infants do anticipate their parents' actions during dynamic interactions at rates significantly higher than would be expected by chance. In addition, the frequency with which they do so is associated with child-led joint attention and hand-eye coordination. These findings are the first to reveal infants' action prediction behaviors in a more naturalistic context than prior screen-based studies, and they support the idea that action prediction is inherently linked to motor development and plays an important role in infants' social-cognitive development. A video abstract of this article can be viewed at https://www.youtube.com/watch?v=9HrmcicfiqE.

Using head-mounted eye-trackers to study sensory-motor dynamics of coordinated attention.

In this chapter, we introduce recent research using head-mounted eye-trackers to record sensory-motor behaviors at a high resolution and examine parent-child interactions at a micro-level. We focus on one important research topic in early social and cognitive development: how young children and their parents coordinate their visual attention in social interactions. We start by introducing head-mounted eye-tracking and recent studies conducted using this method. We then present two sets of novel analysis techniques that examine how manual actions of parents and children with and without hearing loss contribute to their attention coordination. In the first set of analyses, we investigated different pathways parents and children used to coordinate their visual attention in toy play. After that, we used Sankey diagrams to represent the temporal dynamics of parents' and children's manual actions prior to and during coordinated attention. These two sets of analyses allowed us to explore how participants' sensory-motor behaviors contribute to the establishment and maintenance of coordinated attention. More generally, head-mounted eye-tracking allows us to ask new questions and conduct new analyses that were not previously possible. With this new sensing technology, the results here highlight the importance of understanding early social interaction from a multimodal, embodied view.

A meta-analysis of the predictability of LENA™ automated measures for child language development.

Early language environment plays a critical role in child language development. The Language ENvironment Analysis (LENA™) system allows researchers and clinicians to collect daylong recordings and obtain automated measures to characterize a child's language environment. This meta-analysis evaluates the predictability of LENA's automated measures for language skills in young children. We systematically searched reports for associations between LENA's automated measures, specifically, adult word count (AWC), conversational turn count (CTC), and child vocalization count (CVC), and language skills in children younger than 48 months. Using robust variance estimation, we calculated weighted mean effect sizes and conducted moderator analyses exploring the factors that might affect this relationship. The results revealed an overall medium effect size for the correlation between LENA's automated measures and language skills. This relationship was largely consistent regardless of child developmental status, publication status, language assessment modality and method, or the age at which the LENA recording was taken; however, the effect was weakly moderated by the gap between LENA recordings and language measures taken. Among the three measures, there were medium associations between CTC and CVC and language, whereas there was a small-to-medium association between AWC and language. These findings extend beyond validation work conducted by the LENA Research Foundation and suggest certain predictive strength of LENA's automated measures for child language. We discussed possible mechanisms underlying the observed associations, as well as the theoretical, methodological, and clinical implications of these findings.

Individual Differences in Mothers' Spontaneous Infant-Directed Speech Predict Language Attainment in Children With Cochlear Implants.

Purpose Differences across language environments of prelingually deaf children who receive cochlear implants (CIs) may affect language acquisition; yet, whether mothers show individual differences in how they modify infant-directed (ID) compared with adult-directed (AD) speech has seldom been studied. This study assessed individual differences in how mothers realized speech modifications in ID register and whether these predicted differences in language outcomes for children with CIs. Method Participants were 36 dyads of mothers and their children aged 0;8-2;5 (years;months) at the time of CI implantation. Mothers' spontaneous speech was recorded in a lab setting in ID or AD conditions before ~15 months postimplantation. Mothers' speech samples were characterized for acoustic-phonetic and lexical properties established as canonical indices of ID speech to typically hearing infants, such as vowel space area differences, fundamental frequency variability, and speech rate. Children with CIs completed longitudinal administrations of one or more standardized language assessment instruments at variable intervals from 6 months to 9.5 years postimplantation. Standardized scores on assessments administered longitudinally were used to calculate linear regressions, which gave rise to predicted language scores for children at 2 years postimplantation and language growth over 2-year intervals. Results Mothers showed individual differences in how they modified speech in ID versus AD registers. Crucially, these individual differences significantly predicted differences in estimated language outcomes at 2 years postimplantation in children with CIs. Maternal speech variation in lexical quantity and vowel space area differences across ID and AD registers most frequently predicted estimates of language attainment in children with CIs, whereas prosodic differences played a minor role. Conclusion Results support that caregiver language behaviors play a substantial role in explaining variability in language attainment in children receiving CIs. Supplemental Material https://doi.org/10.23641/asha.12560147.