The first window infants have into language acquisition comes from listening to their caregivers. My research along this line focuses on infant-directed speech (IDS), a speech style that caregivers normally use when talking to young children. The aims of my work in this area are to (1) characterize acoustic and phonological properties of IDS, and (2) understand the underlying mechanisms by which IDS might serve to promote language and cognitive development. This work suggests that IDS promotes language development because it enhances attention in a way that would facilitate learning, instead of highlighting linguistically relevant components for speech processing.

Infants come to language acquisition with perceptual biases that serve as emergent sources of support for spoken language development. One track of my research explores structural biases that infants bring to guide their language acquisition. This work suggests that infants begin their life with a determined set of phonological biases that do not only reflect linguistic universals, but also form a foundation on which specific language experience can build. This initial predisposition sets the stage for learning, perhaps by allowing infants to direct their limited attentional resources to the most relevant information in the environmental input thus maximizing learning.

Pediatric hearing loss and subsequent cochlear implantation lead to more global changes in cognitive functions that play a pivotal role in supporting successful spoken language processing. My research along this line examines how early hearing experience may affect attention to speech skills in children with cochlear implants. This work demonstrates that early auditory deprivation and subsequent degraded auditory input affect attention to speech in deaf infants with cochlear implants; in addition, the degree of attention to speech predicts language outcomes over a period of 10 years. It is possible that greater attention to speech would allow children with CIs better access to speech, leading to better encoding and processing of acoustic-phonetic and phonological information. These findings provide support for further assessing the mechanisms underlying the relationship between attention to speech and language development in children with hearing loss.

Sensitivity to paralinguistic information in speech processing
Much of what we know about the world is learned from other individuals. This is especially true for young children, who have little experience with new objects, entities, and events that occur in their daily lives. One of the most important sources of information that is available to young children is the speech that they hear in their everyday world. The speech signal does not only carry important linguistic information, but also carries a variety of paralinguistic or indexical information, including information about the talker’s social class, emotional state, accent, gender, and age, among others. Sensitivity to talker-specific information is important, as successful processing of information in the speech signal depends on the integration of linguistic and talker-specific information. Further, talker-specific information can influence both behavior and preferences. The primary goal of this research is to examine toddlers’ ability to encode talker-specific information, in the speech signal and whether this sensitivity influences learning.

Dilley, L, Gamache, J., Wang, Y., Houston, D. M., & Bergeson, T. (2019). Statistical distributions of consonant variants in infant-directed speech: /t/ is exceptional. Journal of Phonetics.

Wang, Y., Shafto, C. L., & Houston, D. M. (2018). Attention to speech and language development in deaf children with cochlear implants: A 10-year longitudinal study. Developmental Science. 

Wang, Y., Bergeson, T. R., & Houston, D. M. (2018). Preference for infant-directed speech in infants with hearing aids: effects of early auditory experience. Journal of Speech, Language, and Hearing Research, 61 (9), 2431-2439. 

Wang, Y., & Houston, D. M. (2018). Attention to speech, speech perception, and referential learning. Commentary on Janet Werker's keynote article \Perceptual beginnings to language acquisition". Applied Psycholinguistics, 39 (4), 764-768. 

Wang, Y., Bergeson, T. R., & Houston, D. M. (2017). Infant-directed speech enhances attention to speech in deaf infants with cochlear implants. Journal of Speech, Language, and Hearing Research, 60, 3321-3333. 

Wang, Y., Llanos, F., & Seidl, A. (2017). Infants adapt to speaking rate differences in word segmentation. The Journal of Acoustical Society of America, 141(4), 2569-2578. DOI: 10.1121/1.4979704

Wang, Y., Lee, C. S., & Houston, D. M. (2016). Infant-directed speech reduces 9-month-olds' preference for the predominant stress pattern. The Journal of Acoustical Society of America, 140(6), 4101-4110. DOI: 10.1121/1.4968793

Wang, Y., & Seidl, A. (2016). Twenty-four-month-olds' perception of word-medial on-sets and codas. Language Learning and Development, 12(4), 447-460. DOI:10.1080/15475 441.2016.1150185

Wang, Y., Seidl, A., & Cristia, A. (2015). Acoustic-phonetic differences between infant-and adult-directed speech: The role of stress and utterance position. Journal of Child Language, 42(4), 821-842. DOI:10.1017S0305000914000439

Wang, Y., & Seidl, A. (2015). The learnability of phonotactic patterns in onset and coda positions. Language Learning and Development, 11 (1), 1-17.

*corresponding author

 

Society for Improvement of Psychological Science Mission Award for improving psychological science in the face of challenge, as contributor to the ManyBabies1 Collaboration