Dynamic center-of-gravity effects in consonant–vowel transitions

Abstract

Lublinskaja has reported that dynamic changes in the spectral center-of-gravity (COG) of one formant in selected Russian vowels led to changes in the identification of the vowel. Movement of the COG was effected by simultaneous amplitude modulation of two formants placed at the end points of the desired frequency transition [Iyer et al., J. Acoust. Soc. Am. 109, 2294 (2001)]. The present study explores whether such COG effects will extend into the processing of consonant–vowel transitions (CVs). A [dɑ]–[gɑ] continuum was generated using a Klatt synthesizer with a 50-ms CV transition and a 200-ms vowel. The onset of F3 varied from 2018–2818 Hz in 80-Hz step. The F3 of the vowel remained constant at 2527 Hz. Three different stimulus sets differed in terms of whether the F3 transition was a: (1) formant, (2) FM tone, or (3) virtual frequency (VF) glide. In the VF stimuli, the frequencies of two tones matched the onset or offset frequencies of the F3 transition and modulation of their amplitudes produced a gliding spectral COG. Preliminary results indicate that listener performance is not strongly affected by changing the means by which spectral changes to F3 are made. [Research supported by a grant from OSU’s College of Social and Behavioral Sciences to L. Feth and an INRS award from NIH to R. Fox.]