Vowel duration as a perceptual cue to postvocalic consonant voicing in young children and adults.

Vowel duration is a powerful acoustic cue for adults' perception of postvocalic consonant voicing, but it has not been studied sufficiently in children. The purpose of the present work was to study the development of the use of this duration cue in 3-year-olds, 6-year-olds, and adults. The duration of the vowel was varied to construct three stimulus continua (BIP-BIB, POT-POD, BACK-BAG). The subjects, who had normal language, articulation skills, and hearing sensitivity, identified all stimuli from each of the three continua ten times. Significant developmental differences in the perceptual judgments of voicing were demonstrated. These differences were reflected in both the locus of the category boundary and the slope of the identification function.