Comparison of frequency-modulated glides with virtual frequency glides in direction identification

Abstract

Four listeners were asked to identify the direction of frequency change, up versus down, for frequency-modulated (FM) and virtual-frequency (VF) glides. VF glides are generated by co-modulating a pair of fixed-frequency tones so that the spectral center-of-gravity moves. Performance in direction identification (D-ID) decreased as glide duration decreased for both types of glides. Further, performance was better when the glide increased in frequency than when it decreased. Finally, the VF D-ID task was more difficult than the FM task, but the patterns of performance were similar. These results suggest similar processing mechanisms for the two types of glides.