Impact of Respiratory Discomfort on Vocal Quality and Perceived Effort: The Moderating Role of Fear.

Abstract

Objectives/hypothesis: The goal of this study was to investigate the relationship between respiratory discomfort and voice measures, including perceived vocal effort and selected acoustic parameters. A secondary aim was to examine whether threat appraisal-measured as susceptibility to experience fear of suffocation-modulated these relationships. We hypothesized that greater dyspnea would predict worse voice outcomes, especially in speakers with greater fear susceptibility.

Study design: Repeated measures study.

Methods: Fifty-eight healthy females were submitted to various levels of respiratory discomfort through rounds of breath-holding while they rated their perceived dyspnea. Participants performed a phonation task-in a comfortable and a loud voice-immediately after each breath hold and rated their perceived vocal effort and fear of suffocation. Smoothed cepstral peak prominence (CPPS), harmonics-to-noise ratio (HNR), mean fundamental frequency (mean F₀), relative level of high-frequency noise (Hfno), and amplitude difference between the first two harmonics (H₁-H₂) were extracted. Linear mixed models and repeated measures correlations were generated to assess the relationships between dyspnea, fear susceptibility, and voice measures.

Results: In the vocal effort models for comfortable and loud phonation, dyspnea was a significant predictor (P < 0.0001) and interacted significantly with fear susceptibility (P < 0.0001). In the comfortable condition, dyspnea was also found to be a significant predictor for CPPS (P = 0.0014) and mean F₀ (P = 0.0003) and interacted significantly with fear susceptibility in the CPPS model (P = 0.0051). Post hoc analyses showed that perceived vocal effort increased as dyspnea intensified, especially in participants with greater fear susceptibility. The direction of CPPS fluctuations with increasing dyspnea varied based on level of fear susceptibility, although correlations were weak.

Conclusions: The relationships between respiratory discomfort and voice were influenced by fear, suggesting that sensory and affective mechanisms interact when impacting voice production and vocal effort perception. Future studies could investigate whether similar interactions may impact laryngeal function in voice and upper airway disorders.