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 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…

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)…

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…

At the babbling stage, the syllable does not have the temporal characteristics of adult syllables because of the infant's limited oro-motor skills. This research aims to further our knowledge of syllable duration and temporal variability and their evolution with age as an indicator of the development of articulatory skills. The possible impact of…

The validity of the Language ENvironment Analysis (LENA) System was evaluated for Dutch. 216 5-min samples (six samples per age per child) were selected from daylong recordings at 5, 10 and 14 months of age of native Dutch-speaking younger siblings of children with autism spectrum disorder (N=6) and of typically developing children (N=6). Two…

Fourteen-month-old infants are unable to link minimal pair nonsense words with novel objects (Stager & Werker, 1997). Might an adult's productions in a word learning context support minimal pair word-object association in these infants? We recorded a mother interacting with her 24-month-old son, and with her 5-month-old son, producing nonsense…

Infant-directed speech (IDS) is a specific register that adults use to address infants, and it is characterised by prosodic exaggeration and lexical and syntactic simplification. Several authors have underlined that this simplified speech becomes more complex according to the infant's age. However, there is a lack of studies on lexical and…

Social feedback is a driving force for speech development. A recent study provided a key finding to explain how contingent responses influence developmental change: infant speech-related vocalizations are contingent on responses to prior speech-related vocalizations (Warlaumont "et al.," 2014). However, the study did not distinguish…

There have been many studies examining the differences between infant-directed speech (IDS) and adult-directed speech (ADS). However, investigations asking whether mothers clarify vowel articulation in IDS have reached equivocal findings. Moreover, it is unclear whether maternal speech clarification has any effect on a child's developing language…

This longitudinal study assessed three acoustic components of maternal infant-directed speech (IDS) -- pitch, affect, and vowel hyperarticulation -- in relation to infants' age and their expressive vocabulary size. These three individual components were measured in IDS addressed to infants at 7, 9, 11, 15, and 19 months (N = 18). All three…

This study investigates the pitch properties of infant-directed speech (IDS) specific to word-learning contexts in which mothers introduce unfamiliar words to children. Using a semi-spontaneous story-book telling task, we examined (1) whether mothers made distinctions between unfamiliar and familiar words with pitch in IDS compared to…

We investigated longitudinal relations among gaze following and face scanning in infancy and later language development. At 12 months, infants watched videos of a woman describing an object while their passive viewing was measured with an eye-tracker. We examined the relation between infants' face scanning behavior and their tendency to follow the…

We examined the functions of mothers' speech to infants during two tasks -- book-sharing and bead-stringing -- in low-income, ethnically diverse families. Mexican, Dominican, and African American mothers and their infants were video-recorded sharing wordless books and toy beads in the home when infants were aged 1;2 and 2;0. Mothers' utterances…

The aim of the present study was to examine the contextual effects of social games on prelinguistic vocalizations. The two main goals were to (1) investigate the functions of vocalizations as symptoms of affective arousal and symbols of social understanding, and (2) explore form-function (de)coupling relations between vocalization types and game…