Self-Perception of Vocal Effort in Response to Modeled Communication Demands.

Objectives: The optimization of vocal effort given a response to a voice demand is a common clinical and vocal performance goal. Increases in vocal effort are often in response to communication limitations from both the interlocutors and the communication environment. This study investigates the relationship between vocal effort and vocal demands from changes and limitations imposed by the communication environment.

Methods: Thirty-seven participants rated their vocal effort associated with a map description task in a range of communication demands. These demands included communication distance (from 1 m to 4 m), loudness goal (54 dB-66 dB), and excess background noise (53 dBA-71 dBA). The vocal effort ratings were compared across the different types and extents of vocal demand conditions.

Results: As would be expected, there were significant increases in vocal effort levels from the control condition to the extremes of the distance and loudness goal vocal demands. Each increase in background noise resulted in distinct increases in vocal effort level. Participants were able to use the vocal effort scale to efficiently quantify expected increases in vocal demands.

Conclusions: Increases of vocal effort level accompany increases to vocal demands that exceed the habitual or expected communication. While voice training and vocal therapy are essential for reducing internal vocal demands, clients with a goal to reduce vocal effort should also consider external vocal demands such as communication distance and background noise.