Amy T. Neel
Dept. of Speech and Hear. Sci., Indiana Univ., Bloomington, IN 47405
Traditionally, target values of F1 and F2 are viewed as primary determinants of vowel identity. Several recent studies, however, have demonstrated the importance of dynamic formant information to vowel identification. The present study examines the contribution of both dynamic and durational information to vowel identification using sine-wave vowel analogs. Sine-wave stimuli consisting of two tones representing F1 and F2 were constructed using careful LPC measurements of ten vowels produced in /dVd/ context by male and female speakers. Four types of stimuli were constructed by varying two factors: (1) appropriate versus fixed vowel duration and (2) variation in tones representing formant movement throughout the token versus static target formant values. Listeners identified the sine-wave vowel analogs using a key-word response form. Results demonstrated that stimuli with appropriate vowel duration were identified with significantly greater accuracy than those with fixed length. For appropriate duration stimuli, there was no significant difference for dynamic versus static tokens. However, for fixed length stimuli listeners identified dynamic tokens with significantly greater accuracy than static stimuli. This suggests that intrinsic vowel duration, as expected, is an important cue to vowel identity and that dynamic formant information is used more by listeners when duration cues are unavailable.