The Immediate Acoustic Effect of Whistling on Vocal Tract Qualities

Abstract

Whistling is a vocalization used in a variety of cultures and contexts. Research on whistling in the context of voice disorders and speech-language pathology is limited. The purpose of this study was to determine what qualities of the human vocal tract are affected immediately following an intervention of whistling. 30 individuals (N=30) were recruited as participants in the library and various public study spaces across the campus of the University of Wisconsin- River Falls. All participants were current students at the University of Wisconsin- River Falls, competent whistlers between the ages of 18 and 25 years old, and had no past or current voice disorders. Each participant completed 3 surveys, which collected their demographic information, vocal health history, and personal perceptions of their voice. The Vocal Comfort Questionnaire was administered a second time following intervention. 28 vocalizations were recorded before and after completing a whistling intervention, which required participants to whistle 3 distinct tones repeatedly. A Shapiro–Wilk test was used to determine the normality of the data. Based on these findings, non-parametric testing (Wilcoxon Signed-Ranked Test, p ≤ .05) was completed on each participant’s fundamental frequency, jitter, shimmer, intensity, H-N ratio, formant 1, and formant 2. Significant differences were found in the jitter of “Ah” and the shimmer of “Ee”. Non-significant differences were found in participants’ perception of their own voice before and after the whistling intervention, and all other vocal tract qualities. Due to the high number of comparisons in our experimental design, a Bonferroni correction was applied to statistically significant differences. Following this correction, all findings showed statistical insignificance. These findings suggest that whistling does not have a statistically significant effect on vocal tract qualities.