Feedback Effects of Audition and Vocal Effort on Intensity of Voice

Abstract

Variations in sidetone gain and in ambient-noise level were found to produce changes in the intensity of voice that were in the direction of constant S/N ratios at the talkers' ears. However, the magnitude of the changes was small and the data fit a model of constant voice level as well as a feedback model. An indirect analysis of the effects of vocal effort on vocal intensity was done, based on the assumption that vocal effort would be proportional to vocal intensity. No evidence was found for feedback control of voice level based on vocal effort. The narrowness of the range of voice levels produced by each subject, in contrast with the wide range of auditory stimulation, suggests that talkers have important nonauditory mechanisms for the control of voice level. Voice-level control, then, appears to depend on both auditory feedback and nonauditory nonfeedback mechanisms.