In children acquiring various languages, the early mastery of determiners strongly predicts syntactic development. What makes determiners important is not yet clear as there is a linguistic controversy regarding their syntactic behaviour. Some consider determiners to be similar to adjectives and to modify common nouns, while others consider the…

Infants begin to understand some of the meanings of the adjective "good" at around thirteen months, but it is not clear when they start to map it to concepts in the moral domain. We investigated infants' and toddlers' knowledge of "good" in the domains of help and fairness. Participants at 20 and 30 months were shown computer…

Purpose: Fathers play a critical but underresearched role in their children's cognitive and linguistic development. Focusing on two-parent families with a mother and a father, the present longitudinal study explores the amount of paternal input infants hear during the first 2 years of life, how this input changes over time, and how it relates to…

Lexical iconicity--signs or words that resemble their meaning--is overrepresented in children's early vocabularies. Embodied theories of language acquisition predict that symbols are more learnable when they are grounded in a child's firsthand experiences. As such, pantomimic iconic signs, which use the signer's body to represent a body, might be…

Purpose: The Index of Productive Syntax (IPSyn; Scarborough, 1990) is widely used to measure syntax production in young children. The goal of this article is to promote greater clarity and consistency in machine and hand scoring by presenting a revised version of the IPSyn (IPSyn-R) and comparing it with the original IPSyn (IPSyn-O). Method:…

We explored whether supported (SJE) or coordinated joint engagement (CJE) between mothers recruited from the community and their 24-month-old children who were slow-to-talk at 18 months old were associated with child language scores at ages 24, 36, and 48 months (n = 197). We further explored whether SJE or CJE modifed the concurrent positive…

Children's speech development begins in infancy. The pattern of this development has been explored in studies over a number of years using a range of research methodology and approaches to investigation. A systematic review of the existing literature was carried out to determine the collective contribution of this literature to our understanding…

This study examines the role of the lexicon and grammatical structure building in early grammar. Parent-report data in CDI format from a sample of 1151 German-speaking children between 1;6 and 2;6 and longitudinal spontaneous speech data from 22 children between 1;8 and 2;5 were used. Regression analysis of the parent-report data indicates that…

In languages with evidential marking, utterances consist of an informational content and a specification of the mode of access to that information. In this first longitudinal study investigating the acquisition of the Turkish evidential marker "-mIs" in naturalistic child-caregiver interactions, we examined six children between 8 and 36…

In typical development, word learning goes from slow and laborious to fast and seemingly effortless. Typically developing 2-year-olds seem to intuit the whole range of things in a category from hearing a single instance named--they have word-learning biases. This is not the case for children with relatively small vocabularies ("late…

For children with normal hearing (NH), early communication skills predict vocabulary, a precursor to grammar. Growth in early communication skills of infants with cochlear implants (CIs) was investigated using the Early Communication Indicator (ECI), a play-based observation measure. Multilevel linear growth modelling on data from six ECI sessions…

This study examines whether children's decontextualized talk--talk about nonpresent events, explanations, or pretend--at 30 months predicts seventh-grade academic language proficiency (age 12). Academic language (AL) refers to the language of school texts. AL proficiency has been identified as an important predictor of adolescent text…

Purpose: This study examined the efficacy of the Vocabulary Acquisition and Usage for Late Talkers (VAULT) treatment in a version that manipulated the length of clinician utterance in which a target word was presented (dose length). The study also explored ways to characterize treatment responders versus nonresponders. Method: Nineteen primarily…

This paper investigates how negation develops in the speech of a Turkish-speaking child in the very early stages of language acquisition. The study features the video recordings of a child between the ages of 19 and 22 months and the analyses of negative forms in the recorded data. The development of negation in parent-child interactions is…

This paper describes an investigation into the function of child-directed speech (CDS) across development. In the first experiment, 10-21-month-olds were presented with familiar words in CDS and trained on novel words in CDS or adult-directed speech (ADS). All children preferred the matching display for familiar words. However, only older toddlers…