Elicitation of Minimum and Maximum Fundamental Frequency and Vocal Intensity: Discrete Half Steps Versus Glissando

Do Flexible Silicone Tubes Immersed in Water Combined With Vocalise Improve the Immediate Effect on Voice?

PURPOSE

This study aimed to analyze the immediate effect on a singer's voice of a flexible silicone tube immersed in water combined with ascending and descending vocalise scales compared with ascending and descending vocalise scales alone.

METHOD

A pre- and post-intervention quasi-experimental study was conducted. Thirty adult singers between 18 and 45 years old with no laryngeal disorders performed the two techniques for 3 min each on different days. Acoustic measurements of frequency, jitter, shimmer, glottal-to-noise excitation ratio, noise, smoothed cepstral peak prominence (CPPS), maximum phonation time (MPT), voice range profile, and self-perceived vocal effort (Borg Category Ratio 10-BR Scale adapted for vocal effort) were assessed before and after performing the techniques.

RESULTS

The results indicated an increase in singers' CPPS and MPT values and a decrease in shimmer and noise when performing with a flexible silicone tube immersed in water combined with vocalise. The singers reported a perception of decreased vocal effort after both methods. However, the diminished perceived vocal effort became more pronounced with the tube phonation technique combined with vocalise.

CONCLUSIONS

Phonation in tubes combined with vocalise improved the vocal acoustic parameters (including cepstral measurements), increased MPT, and diminished perceived vocal effort. Although using vocalise alone diminished perceived vocal effort, this decrease was more pronounced in the tube phonation technique combined with vocalise.

Comparing the Effects of Self-Generated and Platform-Generated Whole Body Vibration on Vocal Fatigue

OBJECTIVES

A whole body vibration platform using vertical oscillation has been shown to be efficacious in reducing vocal fatigue in adults. This study aimed to investigate whether this platform-generated whole body vibration was unique in reducing vocal fatigue by comparing it with self-generated whole body vibration.

METHODS

Twenty-four female adults (mean age = 23.96 years) were randomly assigned to one of the following three groups: a machine-generated whole body vibration group (N = 8), a self-generated whole body vibration group (N = 8), and a placebo vocal resting group (N = 8). All participants performed a karaoke singing task for at least 95 minutes. Each participant received 10 minutes of platform-generated vibration, self-vibration, or sham localised vibration (placebo group with basically voice rest only), according to their group allocation. Vocal function ability, measured by the highest fundamental frequency produced, and a self-reported vocal fatigue score were evaluated at three time points: baseline (prefatigue), after the singing task (post-fatigue) and post-vibration.

RESULTS

The study revealed that machine-generated whole body vibration was significantly better at improving vocal fatigue than self-generated whole body vibration or voice rest.

CONCLUSION

The findings support previous research that machine-generated whole body vibration is effective in reducing vocal fatigue. The non-significant results of self-generated whole body vibration in terms of relieving vocal fatigue suggest that inadequate vibration frequency or amplitude together with leg muscle fatigue may have been the main factor of ineffectiveness.

Vibrational Therapies for Vocal Fatigue

BACKGROUND

Vibration is commonly used to relax tension in the limb and truck muscle. Vibration used directly on the muscle concerned and vertical vibration used on the whole-body through a foot platform have been reported in the literature to be useful to release muscle tension.

AIM

The present study investigated the effect of indirect whole-body vibration (WBV) and direct localized perilaryngeal vibration (LPV) on the phonatory functions of nondysphonic individuals with vocal fatigue.

METHODS

Forty-four subjects (mean age = 21.67 years) with normal voice, were randomly assigned to either the WBV group, the LPV group, or the Control (sham hand-held vibratory device) group. They performed karaoke singing for at least 95 minutes. They then received either WBV through a Turbosonic vibratory machine, LPV with a Novofan vibrator, or a sham vibrator for 10 minutes. The highest pitch produced, and self-reported vocal fatigue score were taken before singing, after singing, and after the intervention. Data were analyzed separately for the gender subgroups.

RESULTS

All subject groups showed significant reduction of vocal function (highest pitch production, and vocal fatigue score) after singing. Following the vibrational interventions, both the WBV and LPV groups showed significantly recovery in the highest pitch production and the perception of vocal fatigue (P < 0.002) than the Control groups.

CONCLUSION

Vibrational therapy, whether it is localized vibration on the peri-laryngeal muscles, or whole-body vibration, is more effective than voice rest per se in relieving vocal fatigue. Vibrational methods are recommended for treating vocal fatigue.

Longitudinal Case Study of Transgender Voice Changes Under Testosterone Hormone Therapy

The purpose of this study was to comprehensively evaluate voice and speech changes in one healthy 30-year-old transgender male undergoing testosterone therapy for transition. Testing occurred at three timepoints before cross-sex hormone therapy and every 2 weeks thereafter for 1 year. Data collected included measures of acoustics, aerodynamics, and laryngeal structure and function via flexible laryngoscopy. Analysis included acoustic correlates of pitch, loudness, voice quality, and vocal tract length, as well as perceptual measures of voice quality and gender. Speaking fundamental frequency (f_o) lowered from 183 Hz to 134 Hz. Phonatory frequency range (ie, minimum and maximum singing range) shifted from a range of D#3-E6 to a range of A2-A5. Perceptual measures of voice quality indicated no negative changes. Naïve listeners reliably rated the participant's speech samples as male after 37 weeks on testosterone. Few studies document in detail the variety of voice changes that occur during cross-sex hormone therapy, focusing instead on f_o alone. This study adds to the literature a comprehensive case study of speech and voice changes experienced by one transmasculine participant undergoing testosterone therapy.