Dynamic center of gravity effects: Matching virtual frequency glides

Abstract

Lublinskaja (1996) demonstrated that changing the amplitudes of two‐resonance Russian vowels over time leads listeners to hear a glidelike transition that follows the dynamic center of gravity (COG). Anantharaman (1998) investigated COG transitions for sinusoidal signals by asking subjects to match frequency‐modulated (FM) to virtual frequency (VF) glides. The amplitudes of two tones were simultaneously modulated to produce a percept of a glide with rising pitch, similar to that of an FM sweep, although the frequencies remained fixed. However, listeners might perform Anantharaman’s task by simply attending to the location of one of the anchor tones without perceiving the virtual glide, as the frequencies of the two component tones were changed to alter the frequency span of the VF glide. This study modified that work by fixing the anchor frequencies, but confirmed the potential for procedural artifacts. Two additional experiments eliminated FM signals altogether and asked listeners to match VF glides to VF glides. Even with anchor frequency roving, subjects were able to match the VF glide trajectories for frequency separations up to 6 to 8 ERB. Results were compared with predictions from the perceptual spectral centroid model. [Research supported by a grant from NIH/NIDCD R01‐DC006879.]