The role of consonants and vowels in lexical recognition at 5 months

Bouchon, C. 1, 2, 3 & Nazzi, T. 1, 2, 3

1 University Paris Descartes ? Laboratoire de Psychologie de la Perception UMR 8158
2 CNRS ? UMR 8158
3 LabEx Empirical Foundations of Linguistics

At 6 months infants already know a few sound patterns (Mandel et al., 1995; Tincoff & Juszcyk, 1999; 2011;
Bergelson & Swingley, 2012), and use familiar words to segment unfamiliar words from fluent speech (Bortfeld et al., 2005; Mersad & Nazzi, 2012). This study investigates the relative contribution of consonants (Cs) and vowels (Vs) to lexical recognition before 6 months. Cs carry more information at the lexical level (Nespor et al., 2003), yielding to a consonantal bias in lexical tasks in adults and infants older than 14 months. While a consonantal bias was observed at 12 and 8 months (respectively: Hochmann et al., 2011; Nishibayashi & Nazzi, 2012), 6?montholds exhibited a reversed vocalic bias in a lexical task (Hochmann, 2010). It is still unknown how much speech exposure infants need before Cs, although acoustically less salient and phonetically less defined than Vs, become preferential cues in word processing. 5 month?olds already recognize their own names (Mandel et al., 1995) and ERPs show that this recognition occurs from the first phoneme (Parise et al., 2010). Using HPP, we tested the sensitivity of French?learning 5?month?olds to a minimal initial phonetic change in their name, by presenting them with repetitions of their correctly vs. mispronounced names. To determine the relative weight of Cs and Vs, this change was either consonantal (n=30, e.g. victor/zictor) or vocalic (n=26, e.g. eliot/øliot). The vocalic change yielded a strong preference for the name (p = .002), whereas the consonantal change did not (p = .26). Results in control groups ruled out acoustic effects. Thus the consonantal bias might not have emerged yet by 5 months of age, and infants may be relying mostly on acoustic saliency to detect phonetic changes in familiar words.