Immediate Effects of Semi-Occluded Vocal Tract Exercises on Acoustic, Auditory-Perceptual, and Self-Perceptual Measures of Voice Production.

Introduction: This study examined the immediate acoustic, auditory-perceptual, and self-perceptual effects of two semi-occluded vocal tract exercises (SOVTs): straw phonation and straw phonation into a cup of water, delivered in a remote setting.

Method: Thirty-six participants (19 females and 17 males) completed a baseline battery of acoustic recordings, followed by one of two SOVTs, and an identical post-task battery. The procedure repeated itself to include the other SOVT. Participants were also asked to rate their self-perceived vocal effort and quality following each condition. Recordings were presented to three expert listeners for completion of auditory-perceptual analysis.

Results: Acoustically, a significant decrease in shimmer was noted following straw phonation. Auditory-perceptual analysis revealed a significant increase in the perception of strain following straw phonation into a cup of water. While no significant differences were found between SOVT tasks in self-perception of vocal effort, a significant increase in self-perception of vocal loudness was reported following straw phonation into a cup of water.

Conclusion: SOVTs have a varied, yet significant short-term impact across acoustic, auditory-perceptual, and self-perceptual measures of voice production. Straw phonation provided consistently significant acoustic results, with nearly every variable improving to some degree. Results also support the notion that shimmer is an acoustic measure that is particularly susceptible to change following modest manipulation. These results, in addition to the auditory-perceptual and self-perceptual findings, have a direct impact on how SOVTs are being used clinically and may generalize to inform the way voice metrics are collected and analyzed.