Words and syllables in fluent speech segmentation by French-learning infants: an ERP study.

In order to acquire their native language, infants must learn to identify and segment word forms in continuous speech. This word segmentation ability is thus crucial for language acquisition. Previous behavioral studies have shown that it emerges during the first year of life, and that early segmentation differs according to the language in acquisition. In particular, linguistic rhythm, which differs across classes of languages, has been found to have an early impact on segmentation abilities. For French, behavioral evidence showed that infants could use the rhythmic unit appropriate to their native language (the syllable) to segment fluent speech by 12months of age, but failed to show whole word segmentation at that age, a surprising delay compared to the emergence of segmentation abilities in other languages. Given the implications of such findings, the present study reevaluates the issue of whole word and syllabic segmentation, using an electrophysiological method, high-density ERPs (event-related potentials), rather than a behavioral technique, and by testing French-learning 12-month-olds on bisyllabic word segmentation. The ERP data show evidence of whole word segmentation while also confirming that French-learning infants rely on syllables to segment fluent speech. They establish that segmentation and recognition of words/syllables happen within 500ms of their onset, and raise questions regarding the interaction between syllabic segmentation and multisyllabic word recognition. Copyright 2010 Elsevier B.V. All rights reserved.