Context-sensitive perception of naturally produced stop and fricative consonants by infants.

Abstract

In six separate experiments using controlled natural stimuli and a modification of the high-amplitude sucking paradigm, infants’ ability to perceive voicing differences in stop and fricative consonants in both prevocalic and postvocalic position was assessed. An attempt was also made to investigate the role of vowel duration as a supplemental cue to the difference between postvocalic voiced and voiceless consonants for infants. Results of a previous experiment by Trehub and Rabinovitch [Dev. Psycho. 6, 74–77 (1972)] indicate that infants have little difficulty perceiving the difference between the stop consonants [d] and [t] in prevocalic position. Present results indicate that infants discriminate postvocalic [d] and [t], even when vowel-duration cues are minimized in the vowel–consonant (VC) syllables. However, no evidence of discrimination was observed when durational differences were presented in the absence of voicing differences in consonants. In contrast, perception of the difference between the fricative consonants [s] and [z] could not be demonstrated either in consonant–vowel (CV) syllables or in VC syllables with vowel-duration cues minimized. Evidence of discrimination was obtained in VC syllables when the [s] and [z] stimuli differed in vowel duration, frication duration, formant-transition information, and voicing.