Various measures of infant responsiveness have been shown to predict child outcomes. Despite this extensive research, there is no work examining links between infant responsiveness during caregiver-infant interactions with infants' ability to perform basic linguistic tasks. One key task in early linguistic development is word segmentation, an achievement that allows infants to build their mental dictionaries. We hypothesized that infants' responsiveness to caregiver facial expressions might be related to their word segmentation ability.In order to test this hypothesis, mothers came into the lab and were videotaped reading books containing target words to their 5-month-old children. After the infants were read to, we tested their listening preference for words in the books, as well as novel words; this test yielded a preference score (preference for familiar vs. unfamiliar words). We also used the videotaped reading to code facial expressions for both infant and caregiver, and subsequently, we tabulated occasions where synchronous facial expressions occurred for each member of the dyad.We then examined possible correlations between our preference score and measures gleaned from the dyadic facial expression coding. Although neither the number of infant-led synchronous facial expressions nor the total number of facial expressions produced by either member was significantly correlated with preference score, our measure of synchronous facial expressions led by the caregiver was highly correlated with preference score. Thus, results support the hypothesis that infant responsiveness during caregiver-infant interaction, as indexed by synchronous facial expressions with caregivers, may be related to language learning ability.Kish, A., Courtaney, K., Dilger, A., Gallo, T., Jarvis, A., King, L., . . . Thottichira, S. (2014 Student AuthorsAmanda Seidl is an associate professor in the Speech, Language, and Hearing Sciences Department. The overarching goal of her research is to discover how language comes to the child. Seidl's current research program focuses on early predictors of language. Specifically, this work explores the ways in which measures of early speech perception, production, and the input to the child relate to later language in both typical development and in children at risk for autism spectrum disorders. MentorsRana Abu-Zhaya is a PhD student in the Speech, Language, and Hearing Sciences Department. She has worked as a speech-language pathologist in Israel and is exploring the role of dyadic interactions in the course of language acquisition for her PhD work, focusing on effects of caregiver touch on infant word segmentation and learning.