Developmental changes in voiceless fricative production: Influence of position in words

Abstract

Children master the production of fricative consonants later than other phonemes [Moeller et al., Ear Hear. 28, 605-627 (2007)]. Even though recognizable fricative categories are present before school age, fine-tuning of acoustic properties may continue throughout early adolescence [Nissen & Fox, J. Acoust. Soc. Am. 118, 2570-2578 (2005)]. Previous acoustic studies on the development of fricative production focused on those in word-initial position only. Even in adults’ speech, acoustics of consonants in word-medial or word-final positions vary more compared to those in the word-initial position. The present study hypothesized that adult-like production of fricatives in the word-final position may be achieved later than those in the word-initial position due to the acoustic variability in the adult exemplars children hear. Thirty-six (six each of 4-, 6-, 8-, 10-, 12-year-olds and adults) female native speakers of American English recorded five tokens of 16 consonant-vowel-consonant monosyllabic real words containing voiceless fricative consonants /f θ s ∫/ in initial or final position in /i/ and /ɑ/ vowel contexts. Each token was analyzed for frication duration, amplitude, and several spectral measures. Results will be discussed in terms of fricative position in word, vowel context, and speaker age. [Work supported by NIDCD R03 DC009334 and P30 DC004662.]