Assessing the impact of conversational overlap in content on child language growth

VocabStudy: A remote collection of naturalistic topic-structured parental speech and toddlers' vocabularies using a mobile phone application

The current work presents VocabStudy, a collection of natural language samples and children's vocabularies collected remotely by parents via a mobile phone application. The corpus contains 567,003 word tokens and represents 144 hours of speech over a period of six months from the language environment of 63 British toddlers aged 13 to 28 months. The corpus incorporates labeled speech samples of five typical routines: mealtime, bedtime, playtime, bathtime, and nappytime (i.e., diaper). To explore consistency and variability across these five linguistic contexts, topic modeling was employed. The topic most successfully detected as having a unique structure was mealtime, which was identified as such nearly 100% of the time; bathtime, nappytime, and bedtime were found to cluster together most of the time, suggesting that they have a similar language structure; playtime was correctly identified as such about 14% of the time. To validate the accuracy of parents marking the words that their child produced, the child's utterances found in the audio recordings were examined. About 18% of the vocabulary reported by parents appeared in the transcripts, and the reported vocabulary sizes were highly correlated with the number of unique words uttered by the children (ρ = .72, p < 001). The results suggest that most parents marked the words soon after their children start producing them (p < .001, d = 0.9). I discuss the advantages and disadvantages of using a mobile phone application as a method to collect children's data remotely, what worked to keep participants entering data, and what could have been done to avoid some issues encountered.

Lexical Alignment is Pervasive Across Contexts in Non-WEIRD Adult-Child Interactions

Lexical alignment, a communication phenomenon where conversational partners adapt their word choices to become more similar, plays an important role in the development of language and social communication skills. While this has been studied extensively in the conversations of preschool-aged children and their parents in Western, Educated, Industrialized, Rich, and Democratic (WEIRD) communities, research in other pediatric populations is sparse. This study makes significant expansions on the existing literature by focusing on alignment in naturalistic conversations of school-aged children from a non-WEIRD population across multiple conversational tasks and with different types of adult partners. Typically developing children aged 5 to 8 years (n = 45) engaged in four semi-structured conversations that differed by task (problem-solving vs. play-based) and by partner (parent vs. university student), resulting in a corpus of 180 conversations. Lexical alignment scores were calculated and compared to sham conversations, representing alignment occurring at the level of chance. Both children and adults coordinated their conversational utterances by re-using or aligning each other's word choices. This alignment behavior persisted across conversational tasks and partners, although the degree of alignment was moderated by the conversational context. These findings suggest that lexical alignment is a robust phenomenon in conversations between school-age children and adults. Furthermore, this study extends lexical alignment findings to a non-WEIRD culture, suggesting that alignment may be a coordination strategy employed by adults and children across diverse linguistic and cultural backgrounds.

A comparison of automatic and manual measures of turn-taking in monolingual and bilingual contexts

The Language ENvironment Analysis system (LENA) records children's language environment and provides an automatic estimate of adult-child conversational turn count (CTC) by automatically identifying adult and child speech in close temporal proximity. To assess the reliability of this measure, we examine correlation and agreement between LENA's CTC estimates and manual measurement of adult-child turn-taking in two corpora collected in the USA: a bilingual corpus of Spanish-English-speaking families with infants between 4 and 22 months (n = 37), and a corpus of monolingual families with English-speaking 5-year-olds (n = 56). In each corpus for each child, 100 30-second segments were extracted from daylong recordings in two ways, yielding a total of 9300 minutes of manually annotated audio. LENA's CTC estimate for the same segments was obtained through the LENA software. The two measures of CTC had low correlations for the segments from the monolingual 5-year-olds sampled in both ways, and somewhat higher correlations for the bilingual samples. LENA substantially overestimated CTC on average, relative to manual measurement, for three out of four analysis conditions, and limits of agreement were wide in all cases. Segment-level analyses demonstrated that accidental contiguity had the largest individual impact on LENA's average CTC error, affecting 12-17% of analyzed segments. Other factors significantly contributing to CTC error were speech from other children, presence of multiple adults, and presence of electronic media. These results indicate wide discrepancies between LENA's CTC estimates and manual CTCs, and call into question the comparability of LENA's CTC measure across participants, conditions, and developmental time points.

Caregiver linguistic alignment to autistic and typically developing children: A natural language processing approach illuminates the interactive components of language development

BACKGROUND

Language development is a highly interactive activity. However, most research on linguistic environment has focused on the quantity and complexity of linguistic input to children, with current models showing that complexity facilitates language in both typically developing (TD) and autistic children.

AIMS

After reviewing existing work on caregiver engagement of children's utterances, we aim to operationalize such engagement with automated measures of linguistic alignment, thereby providing scalable tools to assess caregivers' active reuse of their children's language. By assessing the presence of alignment, its sensitivity to the child's individual differences and how well it predicts language development beyond current models across the two groups, we showcase the usefulness of the approach and provide initial empirical foundations for further conceptual and empirical investigations.

METHODS

We measure lexical, syntactic and semantic types of caregiver alignment in a longitudinal corpus involving 32 adult-autistic child and 35 adult-TD child dyads, with children between 2 and 5 years of age. We assess the extent to which caregivers repeat their children's words, syntax, and semantics, and whether these repetitions predict language development beyond more standard predictors.

RESULTS

Caregivers tend to re-use their child's language in a way that is related to the child's individual, primarily linguistic, differences. Caregivers' alignment provides unique information improving our ability to predict future language development in both typical and autistic children.

CONCLUSIONS

We provide evidence that language development also relies on interactive conversational processes, previously understudied. We share carefully detailed methods, and open-source scripts so as to systematically extend our approach to new contexts and languages.

Spontaneous verbal repetition in toddler-adult conversations: a longitudinal study with Spanish-speaking two- year-olds

The role of children's verbal repetition of parents' utterances on vocabulary growth has been well documented (Masur, 1999). Nevertheless, few studies have analyzed adults' and children's spontaneous verbal repetition around the second birthday distinguishing between the types of repetition. We analyzed longitudinally Spanish-speaking parent-child dyads during spontaneous interaction at 21, 24 and 30 months. Linguistic level was measured using the Spanish version of the MacArthur CDI (López-Ornat et al., 2005). Children's and adults' repetitions are about 17% of the speech. Children repeated adults' utterances in a reduced manner whereas adults produced more extended repetitions. Adults' rate of repetition predicted children's linguistic level at 30 months. Children's rate of repetition did not predict linguistic level. These results suggest that parents adapt their speech to children's communicative abilities. Since children's rate of repetition did not predict linguistic level, we suggest that verbal imitation plays an indirect and complex role in communicative development.

Teachers' Use of Scaffolds Within Conversations During Shared Book Reading

PURPOSE

We studied conversations initiated through teacher questions during shared book reading in prekindergarten and kindergarten classrooms as these conversations provide opportunities for the teacher to scaffold emerging language skills. This study provides detailed analysis of scaffolding strategies used by teachers after children answered teachers' questions.

METHOD

Participants included 93 prekindergarten and kindergarten teachers who read aloud a standard narrative text to their class of students. All the sessions were video-recorded, transcribed, and then coded for conversational turns and teacher scaffolding strategies.

RESULTS

Descriptive findings showed great variability in the length of conversations and the extent to which teachers used scaffolding strategies. Most teacher scaffolds matched children's accuracy of response such that they provided support after incorrect responses and provided additional challenge after correct responses. Significant sequential associations were observed between the level of children's response and multiple types of scaffolds (e.g., corrective feedback scaffold after incorrect response; discussing factual questions after a correct response).

CONCLUSIONS

Findings indicate that during shared reading, teachers are responsive to children's answers and are able to provide challenge or support as needed. However, teachers infrequently used scaffolding strategies like causal effects, predictions, and recasts. Given evidence that strategies such as recasts support early language skills, professional development experiences could encourage early childhood teachers to incorporate this and other key scaffolding strategies.

The Longitudinal Relationship Between Conversational Turn-Taking and Vocabulary Growth in Early Language Development

Children acquire language embedded within the rich social context of interaction. This paper reports on a longitudinal study investigating the developmental relationship between conversational turn-taking and vocabulary growth in English-acquiring children (N = 122) followed between 9 and 24 months. Daylong audio recordings obtained every 3 months provided several indices of the language environment, including the number of adult words children heard in their environment and their number of conversational turns. Vocabulary was measured independently via parental report. Growth curve analyses revealed a bidirectional relationship between conversational turns and vocabulary growth, controlling for the amount of words in children's environments. The results are consistent with theoretical approaches that identify social interaction as a core component of early language acquisition.

Infant language predicts fathers' vocabulary in infant-directed speech

Research on sources of individual difference in parental Infant-Directed Speech (IDS) is limited and there is a particular lack of research on fathers' compared to mothers' speech. This study examined the predictive relations between infant characteristics and variability in paternal lexical diversity (LD) in dyadic free play with two-year-olds (M = 24.1 months, SD = 1.39, 35 girls). Ten minutes of interaction for sixty-four father-infant dyads were transcribed and multiple regression analyses were performed to examine the effects of a set of distal and proximal sources of infant influence on paternal LD. Fathers' LD was predicted only by infant language, both standardised language scores and dynamic language measures, and was not predicted by infant age, gender, executive function, or temperament. Findings are discussed in the light of the complex interplay of factors contributing to variability in IDS and the infant's linguistic environment.