Anticipatory coarticulation in the speech of adults and children: A perceptual study

Abstract

Two competing theories attempt to explain anticipatory coarticulation in the speech of adults and children: One suggests more extensive coarticulation in children’s speech than in that of adults, while the other suggests more extensive coarticulation in adult speech [see S. Nittrouer and D. Whalen, J. Acoust. Soc. Am. 86, 1266–1276 (1989) for discussion]. To address this issue, a perceptual experiment was conducted in which adult listeners identified vowel information from gated CV syllables. The syllables /si/, /su/, /∫i/, and /∫u/ produced by children (5 and 7 years old) and adults were gated into four segments of varying lengths (1/2 fricative, 3/4 fricative, full fricative, and fricative +1/2 vowel). The stimuli were presented to ten adult listeners in randomized order (experiment 1) and to another ten listeners, blocked by individual talkers (experiment 2). Syllable identification for key fricative gates was 6% better in blocked compared to random presentation. Both experiments revealed a trend of listeners detecting more extensive coarticulation in children’s productions than in those of adults; however, this pattern resulted from heightened responses to a single 7-year-old talker. Results suggest children coarticulate with greater variability than adults, but not necessarily with a greater temporal extent.