There is considerable controversy over the factors that shape infants' developing knowledge of grammar. Work with artificial languages suggests that infants' ability to track statistical regularities within the speech they hear could, in principle, support grammatical development. However, little work has tested whether infants' performance on…

Iconic words imitate their meanings. Previous work has demonstrated that iconic words are more common in infants' early speech, and in adults' child-directed speech (e.g., Perry et al., 2015; 2018). This is consistent with the proposal that iconicity provides a benefit to word learning. Here we explored iconicity in four diverse language…

This review describes a computational approach for modeling the development of speech motor control in infants. We address the development of two levels of control: articulation of individual speech sounds (defined here as phonemes, syllables, or words for which there is an optimized motor program) and production of sound sequences such as phrases…

Within developmental psychology, pointing gestures have received a great deal of attention, while ostensive gestures have been overlooked in terms of their emergence and intentionality. In a longitudinal and micro-genetic study with six children at 9, 11, and 13 months of age, we codified gesture production of children within second-by-second data…

This research investigates selectivity in word learning for bilingual infants. Previous work demonstrated that bilingual infants show greater openness to non-native language sounds in object labels than monolinguals (Hay et al., 2015; Singh, 2018). It remains unclear whether bilingual openness extends to nonspeech sounds. We presented 14- and…

Children diagnosed with autism spectrum disorder (ASD) often have smaller vocabularies in infancy compared to typically-developing children. To understand whether their smaller vocabularies stem from problems in learning, our study compared a prospective risk sample of 18 elevated risk and 11 lower risk 24-month-olds on current vocabulary size and…

Do parents fine-tune the MLU of utterances with a particular word as the word is on the verge of appearing in the child's production? We analyzed a corpus of spontaneous interactions of 30 dyads. The children were in the initial stages of their lexical development, and the parents' utterances containing the words the children eventually acquired…

Aims: Although IDS is typically described as slower than adult-directed speech (ADS), potential impacts of slower speech on language development have not been examined. We explored whether IDS speech rates in 42 mother-infant dyads at four time periods predicted children's language outcomes at two years. Method: We correlated IDS speech rate with…

We test the comprehension of transitive sentences in very young learners of Mandarin Chinese using a combination of the weird word order paradigm with the use of pseudo-verbs and the preferential looking paradigm, replicating the experiment of Franck et al. (2013) on French. Seventeen typically-developing Mandarin infants (mean age: 17.4 months)…

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…

Both touch and speech independently have been shown to play an important role in infant development. However, little is known about how they may be combined in the input to the child. We examined the use of touch and speech together by having mothers read their 5-month-olds books about body parts and animals. Results suggest that speech+touch…

Previous studies have demonstrated an effect of early vocal production on infants' speech processing and later vocabulary. This study focuses on the relationship between vocal production and new word learning. Thirty monolingual Italian-learning infants were recorded at about 11 months, to establish the extent of their consonant production. In…

We examined the relation between maternal responsiveness and children's acquisition of mental and non-mental state vocabulary in 59 pairs of mothers and children aged 10 to 26 months as they engaged in a free-play episode. Children wore a head camera and responsiveness was defined as maternal talk that commented on the child's actions (e.g., when…

The objective of this study was to examine the links between prosodic features of paternal Infant-Directed Speech (IDS) and child characteristics. Pitch variability measures were extracted from the speech samples of 50 fathers during unstructured play with their two-year-old children. Evidence for a link between child receptive language ability…

Code-switching is a common phenomenon in bilingual communities, but little is known about bilingual parents' code-switching when speaking to their infants. In a pre-registered study, we identified instances of code-switching in day-long at-home audio recordings of 21 French-English bilingual families in Montreal, Canada, who provided recordings…