Computational models of child language development can help us understand the cognitive underpinnings of the language learning process, which occurs along several linguistic levels at once (e.g., prosodic and phonological). However, in light of the replication crisis, modelers face the challenge of selecting representative and consolidated infant…

Purpose: This scoping review considers the acoustic features of a clear speech register directed to nonnative listeners known as foreigner-directed speech (FDS). We identify vowel hyperarticulation and low speech rate as the most representative acoustic features of FDS; other features, including wide pitch range and high intensity, are still under…

In their first year, infants begin to learn the speech sounds of their language. This process is typically modeled as an unsupervised clustering problem in which phonetically similar speech-sound tokens are grouped into phonetic categories by infants using their domain-general inference abilities. We argue here that maternal speech is too…

This dissertation investigated how four factors -- the degree of L2 experience, L1 sound structure, age difference in L1 language development and age of L2 exposure -- affect the perceptual cue weighting of duration and spectral differences for English tense-lax vowel contrasts. Four major hypotheses were tested: desensitization hypothesis (DH)…

Phonotactic patterns are generalizations that govern the order of consonants and vowels, within words and syllables. Certain second-order phonotactic patterns--those that relate multiple sounds within a syllable, such as "if the vowel is [near-close near-front unrounded vowel], then [s] can only appear at the end of the…

Purpose: Depicting the development pattern of vowel perception for children with normal hearing (NH) and cochlear implants (CIs) would be useful for clinicians and school teachers to monitor children's auditory rehabilitation. The study was to investigate the development of Mandarin Chinese vowel perception for Mandarin Chinese native-speaking…

Research attempting to understand the intermediate stages of first-language acquisition and disordered speech has led to the discovery of covert contrast. A covert contrast is a statistically reliable difference between phonemes that is produced by a language learner, but in a way that cannot be heard readily by a listener of the target language.…

Language experience shapes infants' abilities to process speech sounds, with universal phonetic discrimination abilities narrowing in the second half of the first year. Brain measures reveal a corresponding change in neural discrimination as the infant brain becomes selectively sensitive to its native language(s). Whether and how bilingual…

This study explores the use of F0, intensity and duration in the production of two types of prominences in French: primary accent with duration as the main acoustic cue, and secondary accent with F0 and intensity as acoustic cues. These parameters were studied in 13 children using a cochlear implant (CI) and 17 children with a normal hearing (NH),…

The purpose of this article is to report results of an investigation into the production of a covert contrast by native speakers of Korean, Portuguese, and Spanish in the acquisition of the English distinction between the high front vowels /i/ and /?/. A covert contrast is a statistically reliable acoustic distinction made by a language learner…

Purpose: The purpose of this study was to determine whether the degree of dominance of Mandarin-English bilinguals' languages affects phonetic processing of tone content in their native language, Mandarin. Method: We tested 72 Mandarin-English bilingual college students with a range of language-dominance profiles in the 2 languages and ages of…

How are languages learned, and to what extent are learning mechanisms similar in infant native-language (L1) and adult second-language (L2) acquisition? In terms of vocabulary acquisition, we know from the infant literature that the ability to discriminate similar-sounding words at a particular age does not guarantee successful word-meaning…

Languages instantiate many different kinds of dependencies, some holding between adjacent elements and others holding between nonadjacent elements. In the domain of phonology-phonotactics, sensitivity to adjacent dependencies has been found to appear between 6 and 10 months. However, no study has directly established the emergence of sensitivity…

Despite abundant evidence of malleability in speech production, previous studies of the effects of late second-language learning on first-language production have been limited to advanced learners. This dissertation examines these effects in novice learners, finding that experience in a second language rapidly, and possibly inexorably, affects…