Contributions of auditory feedback frequency components on F0 fluctuations

Abstract

Auditory feedback effects on voice F0 control were investigated in terms of the frequency range of feedback harmonic components. The analysis was based on data obtained by a new experimental auditory feedback method called TAF (transformed auditory feedback). This method replaces a natural side tone path with an artificial path which modifies the parameters of the feedback speech sounds in real time, and measures effects in the speech sounds produced [Kawahara and Williams, Vocal Fold Physiology Symposium (1995)]. A series of TAF experiments using sustained vowel phonations with band limitations using high-pass and low-pass filters was conducted. Estimated impulse responses from pitch perception to voice F0 control illustrated that the response is compensatory and can be decomposed into two second-order responses with an initial delay. The results indicated that high-pass filtering does not show significant effects on response parameters while low-pass filtering shows a negative correlation between the cutoff frequency and the response delay. The average response delays for high-pass filtering and low-pass filtering were equivalent for a 800-Hz cutoff frequency. Implications on voice pitch perception will be discussed.