Infants’ Recognition of Vowel Contrasts in a Word Learning Task Suzanne Curtin, Christopher Fennell & Paola Escudero University of Calgary, University of Ottawa, & University of Amsterdam 1.0 Introduction At the end of the first year of life, there is a confluence of two major developments in infant language acquisition. Infants this age are emerging from a period of refining their speech perception skills to native-language contrasts (e.g., Werker & Tees, 1984). Concurrently, the infants’ word learning skills are solidifying. Although infants have some success with word learning prior to 12 months of age (Tincoff & Jusczyk, 1999), the second year of life witnesses a veritable explosion of word comprehension and acquisition (e.g., Feldman, et al., 2000). The key question for the current paper is how speech perception cues influence the emergence of word learning, and vice-versa. 1.1. Word learning in infancy Even very young infants’ have a robust ability to remember word forms, where no meaning is attached to sequences of sounds. Newborns can remember a simple word form for over 24 hours (Swain, Zelazo & Clifton, 1993) and 9- month-old infants can retain the sound patterns of frequently presented words for two weeks (Jusczyk & Hohne, 1997). We see the beginnings of true word comprehension in the second half the first year of life, when infants understand the meaning of a few very frequent word forms. Studies using parental reports of children’s vocabularies suggest that infants as young as 8 months of age comprehend an average of 36 words (Bates, Dale & Thal, 1995). Yet, laboratory studies provide evidence for limited word understanding in this age range. Few experimental studies provide clear evidence of infants’ ability to look correctly toward a referent in the presence of a label (Tincoff & Jusczyk, 1999), and many of these studies indicate only partial success prior to 12-months (see Woodward & Markman, 1998, for a review). Beyond 1 year, however, infants demonstrate comprehension of an increasing number of words in laboratory settings. Beginning around 14 months of age, infants can reliably link words and objects in arbitrary associations, without considerable contextual support, in a lab task (Schafer & Plunkett, 1998; Werker, Cohen, Casasola, Lloyd & Stager, 1998).