Despite the fact that in most communities interaction occurs between the child and multiple speakers, most previous research on input to children focused on input from mothers. We annotated recordings of Sesotho-learning toddlers living in non-industrial Lesotho in South Africa, and French-learning toddlers living in urban regions in France. We…

We examined French-learning toddlers' sensitivity to Subject-Verb agreement with conjoined subjects. In French, a conjoined NP triggers plural agreement even when made up of individual singular NPs. Processing of this infrequent structure in the input (see Corpus Analyses) requires going beyond surface patterns of non-adjacent dependencies to…

The present study applies a multidimensional methodological approach to the study of the acquisition of morphosyntax. It focuses on evaluating the degree of productivity of an infrequent subject-verb agreement pattern in the early acquisition of French and considers the explanatory role played by factors such as input frequency, semantic…

The goal of the current study was to statistically evaluate the reliable scalability of a set of tasks designed to assess Theory of Mind (ToM) without language as a confounding variable. This tool might be useful to study ToM in populations where language is impaired or to study links between language and ToM. Low verbal versions of the ToM tasks…

In this experiment using the conditioned head-turn procedure, 18-month-old French-learning toddlers were trained to respond to either a target noun ("la balle"/"the ball") or a target verb ("je mange"/"I ea"t). They were then tested on target word recognition in two syntactic contexts: the target word was…

Dynamic analyses of language growth tell us how vocabulary and grammar develop and how the two might be intertwined. Analyses of growth curves between 17 and 42 months, based on longitudinal data for 34 children, revealed interesting patterns of vocabulary and grammatical developments. They showed that these patterns were nonlinear, but with…

Using a picture pointing task, this study examines toddlers' processing of phonological alternations that trigger sound changes in connected speech. Three experiments investigate whether 2;5- to 3-year-old children take into account assimilations--processes by which phonological features of one sound spread to adjacent sounds--for the purpose of…

A fundamental question in developmental science is how brains with and without language compute numbers. Measuring young children's verbal reactions in Spain and Finland, we show that, although there is a general arithmetic ability for small numbers that is shared by monkeys and preverbal infants, the development of such initial knowledge in…

Articles in this issue focus on language evolution, variation, and heterogeneity. The following are English translations of the French article titles appearing in the issue: "Irregular Phonetic Development Due to Frequency; Regional Traits in Proto-Romance"; "Linguistic Evolution and Evolution of Perspective in the Comparative…