This study focuses on parental use of parentese: the acoustically exaggerated, clear, and higher-pitched speech produced by adults across cultures when they address infants. While previous research shows that parentese enhances language learning and processing, it is still unclear what drives the variability in the amount of parental parentese…

What are the vocal experiences of children growing up on Malakula island, Vanuatu, where multilingualism is the norm? Long-form audio-recordings captured spontaneous speech behavior by, and around, 38 children (5-33 months, 23 girls) from 11 villages. Automated analyses revealed most children's vocal input came from female adults and other…

Studies of the acquisition of verbs tend to focus on one-verb predicates of the prevalent English type. But in hundreds of languages around the world, multi-verb predicates like serial verb constructions are widely used. It could be reasoned that children should begin producing simple, single-verb predicates before they are able to produce…

Infant-directed speech (IDS) is phonetically distinct from adult-directed speech (ADS): It is typically considered to have special prosody--like higher pitch and slower speaking rates--as well as unique speech sound properties, for example, more breathy, hyperarticulated, and/or variable consonant and vowel articulation. These phonetic features…

Purpose: Mean length of utterance (MLU) is one of the most widely reported measures of syntactic development in the developmental literature, but its responsiveness in young school-age children's language has been questioned, and it has been shown to correlate with nonsyntactic measures. This study tested the extent to which MLU shows measurement…

Bilingual infants must navigate the similarities and differences between their languages to achieve native proficiency in childhood. Bilinguals learning to find individual words in fluent speech face the possibility of conflicting cues to word boundaries across their languages. Despite this challenge, bilingual infants typically begin to segment…

Our aim was to assess whether infants influence the quantity and quality of their mothers' speech to them and, in turn, whether this maternal speech influences children's later language. As 189 mothers interacted with each of their twins at age 0;5, we calculated the number of utterances, the proportion of sensitive utterances, and the proportion…

We reexamine the distribution of nonfinite root forms (NRFs) in Child French on the basis of two novel spontaneous speech corpora focusing on two issues that have increasingly dominated recent analyses of French on the one hand and NRFs/RIs on the other. First, we argue that the level of NRF production peaking at ~24% is in line with the…

This study explored the differences in mean length of utterance (MLU) and mean length of the five longest utterances (MLU5) between 5-6-year-old Mandarin-speaking children, and between typically developing children and children with developmental language disorders (DLD). Eighty-nine typically developing children and 35 children with a DLD…

Purpose: Frequent sounds and frequent words are both acquired at an earlier age and are produced by children more accurately. Recent research suggests that frequency is not always a facilitative concept, however. Interactions between input frequency in perception and practice frequency in production may limit or inhibit growth. In this study, we…

The positive effects of shared book reading on vocabulary and reading development are well attested (e.g., Bus, van Ijzendoorn, & Pellegrini, 1995). However, the role of shared book reading in GRAMMATICAL DEVELOPMENT remains unclear. In this study, we conducted a construction-based analysis of caregivers' child-directed speech during shared…

This study compares the use of the variable (q), which is realized as rural [q] and urban [?], in the speech of twenty-two parents and their twenty-one children from the village of Oyoun Al-Wadi in Syria. The study shows that children acquire the general gendered linguistic pattern of the community but do not replicate the linguistic frequencies…

This study tested the impact of child-directed language input on language development in Spanish-English bilingual infants (N = 25, 11- and 14-month-olds from the Seattle metropolitan area), across languages and independently for each language, controlling for socioeconomic status. Language input was characterized by social interaction variables,…

It is well known that mental state verbs are difficult to acquire, but little is known about the acquisition of mental state language encoded through intonation. Puerto Rican Spanish (PRS) has at least three intonation contours available for marking polar questions (PQs): ¡H*L% marks an utterance as a PQ; H+L*L%, in addition to doing the former,…

This study investigates the developmental trajectory of relative clauses (RCs) in Mandarin-learning children's speech. We analyze the spontaneous production of RCs by four monolingual Mandarin-learning children (0;11 to 3;5) and their input from a longitudinal naturalistic speech corpus (Min, 1994). The results reveal that in terms of the…