The role of rate of transition in place perception

Abstract

Kewley‐Port, Pisoni, and Studdert‐Kennedy [“Perception of static and dynamic acoustic cues to place of articulation in initial stop consonants,” J. Acoust. Soc. Am. 73, 1779–1793 (1983)] showed that initial bilabial and alveolar stops can be reliably identified from information in the first 20 ms of the syllable, including the burst and the beginning of the transition. Identification of stops as velars required a longer stimulus, indicating that a slow change in formant frequencies is characteristic of this place of articulation. If rate of change of formant frequencies is a positive cue to the identification of velar stops, it would be predicted that varying rate of change would affect their identification. To test this prediction, synthetic stop‐vowel stimuli, derived from natural tokens, consisting of all combinations of [b,d,g] and the vowels [i,a], were edited to produce stimuli with four rates of formant transition: 100, 75, 50, and 25 ms. Listeners in this experiment identified place of articulation consistently regardless of rate of transition; specifically, there was no significant interaction between place and rate of transition. This would indicate that a slow formant transition is not necessary if a stop is to be identified as a velar. There was, however, a significant interaction between vowel and place of articulation, which implies that the magnitude, if not the rate, of the transition is a significant cue to place.