HOW DO 4-DAY-OLD INFANTS CATEGORIZE MULTISYLLABIC UTTERANCES

Three experiments, using the high-amplitude sucking procedure, tested whether 4-day-old infants discriminate multisyllabic utterances on the basis of number of syllables or number of phonemes. Experiment 1 showed that infants discriminate 2 large sets of phonetically variable utterances composed of 2- vs. 3-CV (consonant-vowel) syllables. Experiment 2 was run to assess whether infants discriminated the 2 sets on the basis of duration differences between the 2- and 3-CV stimuli. Results indicate that reducing the duration differences does not affect infants' discrimination. Finally, Experiment 3 investigated whether infants discriminate 4- vs. 6-phoneme bisyllabic utterances. The results provide no evidence that infants are sensitive to such a change in number of phonemic constituents. Although not decisive, these results appear to be congruent with the hypothesis that infants perceptually structure complex speech inputs.