Speakers consider their listeners and adjust the way they communicate. One well-studied example is the register of infant-directed speech (IDS), which differs acoustically from speech directed to adults. However, little work has explored how parents adjust speech to infants across different contexts. This is important because infants and parents engage in many activities throughout each day. The current study tests whether the properties of IDS in English vary across three in-lab tasks (sorting objects, free play, and storytelling). We analysed acoustic features associated with prosody, including mean fundamental frequency (F0, perceived as pitch), F0 range, and word rate. We found that both parents’ pitch ranges and word rates varied depending on the task in IDS. The storytelling task stood out among the tasks for having a wider pitch range and faster word rate. The results depict how context can drive parents’ speech adjustments to infants.

A growing body of research has found that talking to young children is positively associated with language outcomes. However, there is tremendous heterogeneity in the design of these studies, which could potentially affect the strength and reliability of this association. The present meta-analysis, comprising 4760 participants across 71 studies, goes beyond prior research by including: 1) more recent studies, 2) non-English-speaking populations, 3) more fine-grained categorization of measures of input, 4) additional moderators, and 5) a multilevel model design allowing us to consider multiple effect sizes per study. We find a moderate association between input and outcomes (R2=0.04-0.07) across four input measures, with some evidence of publication bias. We find no differences in effect size across any of the input measures. Child age and study duration moderated some effects of input. Our findings suggest that language input-outcome associations remain robust but modest across a multitude of contexts and measures.

Mental state verbs (MSVs) describe people’s knowledge, thoughts, feelings and desires, and develop through early childhood. This study used a cross-sectional design and a parental questionnaire to describe the developmental process of MSV use by exploring different trajectories of semantic categories within MSVs. One-hundred-fourteen typically developing, Hebrew-speaking children, ages 1;6–10;0 participated in the study. Their parents completed a questionnaire developed for the current study, which contains MSVs from five semantic categories: desire, emotion, cognition, perception, and psychological, plus physical verbs as a control category. Among them, 58 children (ages 3;2–10;0 years) participated in a narrative task that prompted production of MSVs. Results showed scores increased with age from early childhood to elementary school, demonstrating prolonged development of using MSVs. A minor advantage for girls was found in the younger ages compared with boys. Both, boys and girls had different developmental trajectories for physical, physiological, and desire verbs compared with cognition and emotion verbs. The correlation found between the questionnaire scores and the narrative task supports the validity of the questionnaire for assessing MSV use in children. The results are explained by the complex syntactic structure and abstract meaning of MSVs.

This retrospective study provides insights on linguistic development in exceptional circumstances assessing 378 children (between 2;6 and 3;6) who lived their first years during the COVID-19 pandemic and comparing it with normative data collected before this period (CDI-III-PT; Cadime et al., 2021). It investigates the extent to which linguistic development was modulated by a complex set of factors, including sex, maternal education, book reading, language-promoting practices, COVID-19 infection, parental stress and sleeping problems, considering three periods (during lockdowns, out of lockdowns and at present). The results show a substantial negative effect of the pandemic on both lexical and syntactic development. Considering individual variation, structural equation modelling unveiled a complex scenario in which age, sex, book reading, language-promoting practices, sleeping problems and COVID-19 infection showed a direct effect on linguistic development. Maternal education and parental stress had an indirect effect on children’s language, mediated by book reading and sleeping problems, respectively.

Alexithymia (difficulties identifying and describing feelings) predicts increased risks for psychopathology, especially during the transition from childhood to adolescence. However, little is known of the early contributors to alexithymia. The language hypothesis of alexithymia suggests that language deficits play a primary role in predisposing language-impaired groups to developing alexithymia; yet longitudinal data tracking prospective relationship between language function and alexithymia are scarce. Leveraging data from the Surrey Communication and Language in Education cohort (N = 229, mean age at time point 1 = 5.32 years, SD = 0.29, 51.1% female), we investigated the prospective link between childhood language development and alexithymic traits in adolescence. Results indicated that boys with low language function at ages 4–5 years, and those who later met the diagnostic criteria for language disorders at ages 5–6 years, reported elevated alexithymic traits when they reached adolescence. Parent-reported child syntax abilities at ages 5–6 years revealed a dimensional relationship with alexithymic traits, and this was consistent with behavioral assessments on related structural language abilities. Empirically derived language groups and latent language trajectories did not predict alexithymic traits in adolescence. While findings support the language hypothesis of alexithymia, greater specificity of the alexithymia construct in developmental populations is needed to guide clinical interventions.

We present an exploratory cross-linguistic analysis of the quantity of target-child-directed speech and adult-directed speech in North American English (US & Canadian), United Kingdom English, Argentinian Spanish, Tseltal (Tenejapa, Mayan), and Yélî Dnye (Rossel Island, Papuan), using annotations from 69 children aged 2–36 months. Using a novel methodological approach, our cross-linguistic and cross-cultural findings support prior work suggesting that target-child-directed speech quantities are stable across early development, while adult-directed speech decreases. A preponderance of speech from women was found to a similar degree across groups, with less target-child-directed speech from men and children in the North American samples than elsewhere. Consistently across groups, children also heard more adult-directed than target-child-directed speech. Finally, the numbers of talkers present in any given clip strongly impacted children’s moment-to-moment input quantities. These findings illustrate how the structure of home life impacts patterns of early language exposure across diverse developmental contexts.

In the current pre-registered study, we examined the associations between shared book reading, daily screen time, and vocabulary size in 1,442 12- and 24-month-old Norwegian infants. Our results demonstrate a positive association between shared reading and vocabulary in both age groups, and a negative association between screen time and vocabulary in 24-month-olds. Exploratory analyses revealed that the positive relationship between shared reading and expressive vocabulary in 12-month-olds was stronger in lower SES groups, suggesting that shared reading may act as a compensatory mechanism attenuating potentially impoverished learning environment and parent-infant interactions in low-SES families.

This research investigated the impact of the number of talkers with whom children engage in daily conversation on their language development. Two surveys were conducted in 2020, targeting two-year-olds growing up in Japanese monolingual families. Caregivers reported the number of talkers in three age groups and children’s productive vocabulary via questionnaires. The results demonstrated significant effects of variability in talkers in fifth grade or above in Study 1 (N = 50; male = 23; r = .372) and in adult talkers in Study 2 (N = 175; non-nursery going; male = 76; r = .184) on children’s vocabulary development, after controlling for language exposure time and demographic variables. Possible mediating factors are discussed. This research extends previous findings from immigrant bilingual children to monolingual speakers in Japan, suggesting the potential contribution of available talkers other than caregivers in conversational environments.

Internal state language (ISL) research contains knowledge gaps, including dimensionality and predictors of growth, addressed here in a two-aim study. Parent-reported expressive language from N = 6,373 monolingual, English-speaking toddlers (Mage = 23.5mos, 46% male, 57% white) was collected using cross-sectional and longitudinal data in WordBank. Exploratory and confirmatory factor analyses suggested a best-fitting one-factor model of ISL. The single-factor model of ISL was then submitted to hierarchical linear modeling to evaluate predictors of ISL development. Age 2 ISL production was predicted by child sex, wherein females outperform males, and maternal education, wherein higher education contributes to higher ISL. Only maternal education emerged as a significant predictor of ISL growth. These results provide support to theory suggesting a unitary construct of ISL, as opposed to considering ISL as categorical, and further illustrate linear growth through the second postnatal year that varies as a function of child sex and maternal education.

As a result of the Covid-19 pandemic, public life in many countries ground to a halt in early 2020. The aims of this study were (i) to uncover the language practices of multilingual families during the pandemic, in general and especially regarding homeschooling; and (ii) to determine to what extent the changes in circumstance caused by the pandemic impacted children’s language use and proficiency, and family well-being. Parents from 587 families completed an online survey for 1051 children. Data were analysed using ordinal logistic regression. Our results showed that for most children, there were no changes in language use, proficiency or well-being. When there were changes, these were more likely for (families with) preschool children. Using the heritage language for homeschooling (some or all of the time) did not have a negative impact on Dutch language proficiency, but it did have a positive impact on the heritage language proficiency.

When speaking or writing, people tend to re-use the syntactic structures they recently encountered (structural priming). Individuals differ in the extent to which they are primed (primeability). Previous research has suggested that perspective-taking, that is, the ability to imagine the feelings, thoughts and perceptions of others, predicts the magnitude of priming in adults. The present study investigates if this also holds for monolingual and bilingual children. We primed the possessive structure in monolingual Dutch children and bilingual children with varying L2s. There was individual variation in children’s primeability in both groups. For both monolinguals and bilinguals, we found that the better children were at perspective-taking, the more likely they were to be primed. Dutch language proficiency also influenced children’s primeability: higher language proficiency resulted in more priming in both groups. The findings suggest that structural priming serves a social function which is mediated by perspective-taking abilities.

Combining adjective meaning with the modified noun is particularly challenging for children under three years. Previous research suggests that in processing noun-adjective phrases children may over-rely on noun information, delaying or omitting adjective interpretation. However, the question of whether this difficulty is modulated by semantic differences among (subsective) adjectives is underinvestigated.

A visual-world experiment explores how Italian-learning children (N=38, 2;4–5;3) process noun-adjective phrases and whether their processing strategies adapt based on the adjective class. Our investigation substantiates the proficient integration of noun and adjective semantics by children. Nevertheless, alligning with previous research, a notable asymmetry is evident in the interpretation of nouns and adjectives, the latter being integrated more slowly. Remarkably, by testing toddlers across a wide age range, we observe a developmental trajectory in processing, supporting a continuity approach to children’s development. Moreover, we reveal that children exhibit sensitivity to the distinct interpretations associated with each subsective adjective.

We examined how noun frequency and the typicality of surrounding linguistic context contribute to children’s real-time comprehension. Monolingual English-learning toddlers viewed pairs of pictures while hearing sentences with typical or atypical sentence frames (Look at the… vs. Examine the…), followed by nouns that were higher- or lower-frequency labels for a referent (horse vs. pony). Toddlers showed no significant differences in comprehension of nouns in typical and atypical sentence frames. However, they were less accurate in recognizing lower-frequency nouns, particularly among toddlers with smaller vocabularies. We conclude that toddlers can recognize nouns in diverse sentence contexts, but their representations develop gradually.

There has recently been an increased interest in studying the language development of non-western languages. This is not new - it began in 1960’s and continued into the 1980’s and 1990’s. The current renewed interest is much welcomed, and will benefit from many of the experimental methods and theoretical insights developed over the past decades.

Adolescent pregnancy can impact the educational attainment of adolescent mothers and language development of their children. However, support services and interventions can mitigate these risk factors. Adolescent mothers have shown success in implementing various language facilitation strategies (LFS) with their children when coached. We developed a triadic language intervention in a facilitated playgroup context to support adolescent mothers’ use of language strategies when interacting with their children. The current pilot study utilized a pre-test, post-test descriptive approach to analyze differences in adolescent mothers’ language use and parenting behaviors and their children’s language use after participation in facilitated playgroups. All adolescent mothers demonstrated enhanced parenting practices. Changes in mothers’ and children’s language from pre- to post-test were variable across participants. While this pilot study shows promising evidence of the utility of a triadic intervention situated in playgroups with adolescent families, further research is required to address the limitations of this study.