Discovering words in the continuous speech stream: the role of prosody

Abstract

Finding words in sentences is made difficult by the absence of obvious acoustic markers at word boundaries, such as silent pauses. Recent experimental evidence suggests that both adults and infants are able to use prosodic boundary cues on-line to constrain lexical access. French adults performing a word detection task were slowed down by local lexical ambiguities within phonological phrases but not across a phonological phrase boundary (Christophe, Peperkamp, Pallier, Block, & Mehler, J. Mem. Language (in revision)). Thirteen-month-old American infants who were trained to turn their heads upon hearing a bisyllabic word, such as ‘paper’, in a variant of the conditioned head-turning paradigm, responded more often to sentences that contained the target word than to sentences containing both its syllables separated by a phonological phrase boundary (Gout, Christophe, & Morgan, J. Mem. Language (in revision)). Taken together, these results suggest that both French adults and 13-month-old American infants perceive phonological phrase boundaries as natural word boundaries, and that they do not attempt lexical access on pairs of syllables which span such a boundary. We discuss the potential generalization of these results to other languages, the universality of prosodic boundary cues as well as their use in on-line syntactic analysis and syntax acquisition.