Acoustic correlates of vocal effort: External factors and personality traits

Effects of warm-up exercises on self-assessed vocal effort

PURPOSE

An elevated sense of vocal effort due to increased vocal demand is frequently reported by patients with voice disorders. However, effects of vocal warm-up on self-assessed vocal effort have not been thoroughly examined. A recently developed version of the Borg CR-10 Scale facilitates vocal effort assessments, following different vocal warm-up tasks.

METHODS

Effects of a short (5 min) vocal warm-up on self-assessed vocal effort was evaluated using the Borg CR-10. Twenty-six vocally healthy participants (13F, 13M, mean age 22.6), in two randomised groups, underwent sessions of either reading aloud or semi-occluded vocal tract exercises (SOVTE). Vocal effort was evaluated at four times: pre to post vocal warm-up and two silence periods. Non-parametric analyses for repeated measures and calculations for within-subject standard deviation were applied in group comparisons.

RESULTS

Following vocal warm-up, vocal effort ratings were increased to a statistically significant degree in both intervention groups compared to baseline ratings. After a 5-min rest in silence following completion of the vocal warm-up, vocal effort ratings returned to baseline levels in both groups. The drop in ratings immediately post warm-up compared to 5 min later was statistically significant for the SOVTE group.

CONCLUSIONS

Five minutes of vocal warm-up caused increased self-perceived vocal effort in vocally healthy individuals. The increased sense of effort dissipated faster following warm-up for the SOVTE group. When using the Borg CR-10 scale to track vocal effort, it may be beneficial to apply experience-based anchors.

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.

The effects of theatre-based vocal empowerment on young Egyptian women's vocal and language characteristics

This study investigates the impact of a theatre-based vocal empowerment program on the vocal and language characteristics and the self-perceptions of young bilingual Egyptian women. The program used applied theatre, a dramatic practice that promotes civic action by utilizing improvisational techniques to engage participants in exploring solutions to self-identified community concerns. These techniques supported participants' pursuit of vocal empowerment: the ability to comfortably express their intended content with a clear audible voice, accompanied by the belief that what they had to say was worthwhile. The program was implemented in Alexandria and Aswan, two Egyptian cities in different regions of the country, with distinct socio-economic profiles. Thirty-six young women from Aswan and nineteen from Alexandria participated. The program was facilitated in Arabic, for 90 minutes per day over twelve consecutive days in 2018. Participants in both groups spoke Arabic as a home language and studied English in school settings but differed in their educational experiences and English proficiency. The vocal and language characteristics of each participant were tested in Arabic and English pre- and post- program using a spontaneous speech task and a reading aloud task. Their self-perceptions were evaluated through a vocal self-perception survey. Results indicated that participants responded differently in each city. In Alexandria, participants showed significant improvement in language skills (e.g., mean length of utterance). In contrast, participants in Aswan showed a significant change in fundamental frequency. Overall, the self-surveys indicated that all participants experienced an increased sense of confidence, a stronger belief in self-authorship, and an increased desire to voice their opinions clearly in public; however, there were subtle differences between the groups. In analyzing these results, we conclude that to design effective vocal empowerment outreach programs internationally, it is necessary to consider participants' cultural backgrounds, language diversity, and socio-economic status.