Language Development

Children's ability to share attention with another social partner (joint attention) plays an important role in language development. However, our understanding of the role of joint attention comes mainly from children learning spoken languages, which gives a very narrow, speech-centric impression of the role of joint attention. This study broadens the scope by examining how deaf children learning a sign language achieve joint attention with their caregivers during natural social interaction, and how caregivers provide word learning opportunities. We analyzed naturalistic play sessions of 54 caregiver-child dyads using American Sign Language (ASL), and identified joint attention that surrounded caregivers' labeling of either familiar or novel objects using a comprehensive multimodal coding scheme. We observed that dyads using ASL establish joint attention using linguistic, visual, and tactile cues, and that most naming events took place in the context of a successful joint attention episode. Key characteristics of these joint attention episodes were significantly correlated with the children's expressive vocabulary size, mirroring the patterns observed for spoken language acquisition. We also found that sign familiarity as well as the order of mention of object labels affected the timing of naming events within joint attention. Our results suggest that caregivers using ASL are highly sensitive to their child's visual attention in interactions and modulate joint attention differently when providing familiar versus novel object labels. These joint attentional episodes facilitate word learning in sign language, just as they do in spoken language interactions.

Gastrointestinal symptoms are common during infancy, including infantile colic. Colic can be loosely defined as prolonged and recurrent crying without obvious cause. The cause indeed remains unclear despite much research. Results on infant nutrition are inconclusive, but prior work has linked maternal mental health to infant crying. Recently, several small studies have described associations between gut microbiota and colic. We used a larger cohort to examine the role of the microbiota in infant gastrointestinal health, while also accounting for other biopsychosocial factors. Using fecal 16S rRNA gene amplicon sequencing data from 1,012 infants in the KOALA birth cohort, we examined associations between the 1-month gut microbiota and parent-reported functional gastrointestinal symptoms throughout infancy, including colic, constipation, and cramps. These analyses were adjusted for biopsychosocial factors that were associated with symptoms in a broader analysis involving 2,665 participants. In 257 infants, we also explored associations between breastmilk human milk oligosaccharides (HMOs) and gastrointestinal symptoms. Higher relative abundance of Staphylococcus at one month was associated with less constipation in the first three months of life. Conversely, Ruminococcus gnavus group abundance was associated with more colicky symptoms, particularly between four and seven months. Breastmilk concentrations of the HMOs lacto-N-hexaose (LNH) and lacto-N-neohexaose (LNnH) were associated with less constipation in the first three months. Our results support the conclusion that gut microbiota are relevant in infantile colic and constipation. However more work is needed to elucidate the underlying mechanisms, and explore their interplay with other relevant biopsychosocial factors such as maternal mental health.

BackgroundChildren with developmental language disorder (DLD) have problems acquiring language, affecting their communicative participation, social-emotional functioning (SEF) and quality of life (QoL).AimsTo investigate whether communicative participation mediates the relation between language and SEF and QoL.Methods & proceduresIn a longitudinal design, 511 children were recruited via early intervention groups for children with (presumed) DLD. Language and IQ scores were obtained at a mean age of 3;11 (T0). In kindergarten, communicative participation, SEF and QoL were measured via parental questionnaires (T1, mean age 4;8). The relationship between language and SEF and QoL was investigated directly and with communicative participation as a mediating factor using structural equation modelling.Outcomes & resultsExpressive grammar was related to communicative participation, SEF and QoL, while receptive language and expressive vocabulary were not. Children with better expressive grammar at T0 showed better communicative participation at T1. Better communicative participation, in turn, was related to less problems in SEF and higher QoL. We also found an unexpected positive direct relation between expressive grammar and problems in SEF. Post-hoc analyses showed that this was likely to be a suppressor effect, caused by a small subset of children with relatively good expressive grammar and poor communicative participation.Conclusions & implicationsCommunicative participation is a mediator in the relation between language and SEF and QoL. These results underline the importance of addressing communicative participation as a functional measure of language ability both in research and clinical practice.What this paper addsWhat is already known on the subject Children with DLD have problems acquiring language and communication skills. Alongside and related to these challenges, many children with DLD experience greater problems in SEF and lower levels of QoL, although there is considerable variation among children. Previous research has demonstrated that structural language abilities only explain a small part of the variance in well-being, and more functional language measures, such as pragmatic skills, play an important role. What this paper adds to the existing knowledge This study investigated whether the relation between language problems and well-being is mediated by children's ability to participate in communication (communicative participation). Structural equation modelling in a large, longitudinal sample of children with (presumed) DLD showed that communicative participation mediates the relationship between language abilities and both SEF and QoL. Better expressive grammatical skills were associated with better communicative participation, which in turn was related to higher SEF and QoL scores. Thus, the relation between language and well-being is mediated by how effectively children can communicate in daily life. What are the potential or actual clinical implications of this work? For clinicians, this study underlines the importance of addressing communicative participation as a functional measure of language ability. Measuring communicative participation can aid in identifying a child's specific needs and determining the most suitable setting for providing support. Measuring communicative participation can also assist clinicians in setting treatment goals, evaluating intervention effects, and providing advice to parents and schools. Furthermore, this study underscores the importance of recognizing that early language difficulties can affect well-being.

Adults rate the speech of children assigned male at birth (AMAB) and assigned female at birth (AFAB) as young as 2.5 years of age differently on a scale of definitely a boy to definitely a girl (Munson et al., 2022), despite the lack of consistent sex dimorphism in children's speech production mechanisms. This study used longitudinal data to examine the acoustic differences between AMAB and AFAB children and the association between the acoustic measures and perceived gender ratings of children's speech. We found differences between AMAB and AFAB children in two acoustic parameters that mark gender in adult speech: the spectral centroid of /s/ and the overall scaling of resonant frequencies in vowels. These results demonstrate that children as young as 3 years old speak in ways that reflect their sex assigned at birth. We interpret this as evidence that children manipulate their speech apparatus volitionally to mark gender through speech.