RESUMEN
A reproducible method to measure the intelligibility of communication systems is required to assess their efficiency. The current study seeks to develop a French version of the Modified Rhyme Test (MRT) [(House, Williams, Heker, and Kryter (1965). J. Acoust. Soc. Am. 37, 158-66], an intelligibility test composed of 50 six-word lists, originally developed for military applications and now widely used. An evaluation of the authors' French MRT was carried out, reproducing the original experimental conditions used by House and colleagues. Very similar results were found between the original MRT and the French MRT, validating the latter for further use and dissemination.
RESUMEN
Consonants and vowels differ acoustically and articulatorily, but also functionally: Consonants are more relevant for lexical processing, and vowels for prosodic/syntactic processing. These functional biases could be powerful bootstrapping mechanisms for learning language, but their developmental origin remains unclear. The relative importance of consonants and vowels at the onset of lexical acquisition was assessed in French-learning 5-month-olds by testing sensitivity to minimal phonetic changes in their own name. Infants' reactions to mispronunciations revealed sensitivity to vowel but not consonant changes. Vowels were also more salient (on duration and intensity) but less distinct (on spectrally based measures) than consonants. Lastly, vowel (but not consonant) mispronunciation detection was modulated by acoustic factors, in particular spectrally based distance. These results establish that consonant changes do not affect lexical recognition at 5 months, while vowel changes do; the consonant bias observed later in development does not emerge until after 5 months through additional language exposure.