The prevalent "core phonological deficit" model of dyslexia proposes that the reading and spelling difficulties characterizing affected children stem from prior developmental difficulties in processing speech sound structure, for example, perceiving and identifying syllable stress patterns, syllables, rhymes and phonemes. Yet spoken word…

Psycholinguistic research on children's early language environments has revealed many potential challenges for language acquisition. One is that in many cases, referents of linguistic expressions are hard to identify without prior knowledge of the language. Likewise, the speech signal itself varies substantially in clarity, with some productions…

Language acquisition depends on the ability to detect and track the distributional properties of speech. Successful acquisition also necessitates detecting changes in those properties, which can occur when the learner encounters different speakers, topics, dialects, or languages. When encountering multiple speech streams with different underlying…

The speech register that adults especially caregivers use when interacting with infants and toddlers, that is, infant-directed speech (IDS) or baby talk, has been reported to facilitate language development throughout the early years. However, the neural mechanisms as well as why IDS results in such a developmental faciliatory effect remain to be…

Over half of US children are enrolled in preschools, where the quantity and quality of language input from teachers are likely to affect children's language development. Leveraging repeated objective measurements, we examined the rate per minute and phonemic diversity of child and teacher speech-related vocalizations in preschool classrooms and…

Bilingual and monolingual infants differ in how they process linguistic aspects of the speech signal. But do they also differ in how they process non-linguistic aspects of speech, such as who is talking? Here, we addressed this question by testing Canadian monolingual and bilingual 9-month-olds on their ability to learn to identify native…

Autistic children (AC) show less audiovisual speech integration in the McGurk task, which correlates with their reduced mouth-looking time. The present study examined whether AC's less audiovisual speech integration in the McGurk task could be increased by increasing their mouth-looking time. We recruited 4- to 8-year-old AC and nonautistic…

Noise typically induces both peripheral and central masking of an auditory target. Whereas the idea that a deficit of speech in noise perception is inherent to dyslexia is still debated, most studies have actually focused on the peripheral contribution to the dyslexics' difficulties of perceiving speech in noise. Here, we investigated the…

Newborns are able to extract and learn repetition-based regularities from the speech input, that is, they show greater brain activation in the bilateral temporal and left inferior frontal regions to trisyllabic pseudowords of the form AAB (e.g., "babamu") than to random ABC sequences (e.g., "bamuge"). Whether this ability is…

Teaching a new concept through gestures--hand movements that accompany speech--facilitates learning above-and-beyond instruction through speech alone (e.g., Singer & Goldin-Meadow, 2005). However, the mechanisms underlying this phenomenon are still under investigation. Here, we use eye tracking to explore one often proposed…

Bilingual acquisition presents learning challenges beyond those found in monolingual environments, including the need to segment speech in two languages. Infants may use statistical cues, such as syllable-level transitional probabilities, to segment words from fluent speech. In the present study we assessed monolingual and bilingual 14-month-olds'…

Recent neurophysiological theories propose that the cerebral hemispheres collaborate to resolve the complex temporal nature of speech, such that left-hemisphere (or bilateral) gamma-band oscillatory activity would specialize in coding information at fast rates (phonemic information), whereas right-hemisphere delta- and theta-band activity would…

Gesture is an integral part of children's communicative repertoire. However, little is known about the neurobiology of speech and gesture integration in the developing brain. We investigated how 8- to 10-year-old children processed gesture that was essential to understanding a set of narratives. We asked whether the functional neuroanatomy of…

Previous findings indicate that bilingual Catalan/Spanish-learning infants attend more to the highly salient audiovisual redundancy cues normally available in a talker's mouth than do monolingual infants. Presumably, greater attention to such cues renders the challenge of learning two languages easier. Spanish and Catalan are, however,…

Before infants can learn words, they must identify those words in continuous speech. Yet, the speech signal lacks obvious boundary markers, which poses a potential problem for language acquisition (Swingley, "Philos Trans R Soc Lond. Series B, Biol Sci" 364(1536), 3617-3632, 2009). By the middle of the first year, infants seem to have…