The influence of glottal and respiratory factors on aerosol emission during phonation

<b>Methods:</b> Five healthy female adults (22–43 years) sustained vowels across six phonation types: modal register, glottal fry, falsetto register, force whisper, loud modal register, and vowels preceded by /h/ (i.e., h-onset). Aerosol concentration and size distribution (0.1–20 µm) were measured using an aerodynamic particle sizer (APS). Laryngoscopy, conducted in a separate session on sustained /i/, was used to estimate normalized glottal gap (NGG). Exhaled CO₂ range was recorded concurrently with APS as a control for ventilatory variation across tasks. Bayesian regression models assessed relationships between phonation type, aerosol generation, and physiological predictors.

**研究方法：** 5名年龄介于22至43岁的健康成年女性按照6种发声类型持续发出元音，分别为：模态声区（modal register）、声门颤音（glottal fry）、假声区（falsetto register）、强耳语声（force whisper）、强模态声区（loud modal register），以及以/h/音起首的元音（即h起始元音）。采用空气动力学粒子计数器（aerodynamic particle sizer, APS）测量气溶胶浓度与粒径分布（0.1~20 μm）。在单独的测试环节中，针对持续发出的/i/音进行喉镜检查，以此估算归一化声门间隙（normalized glottal gap, NGG）。同步记录呼出气CO₂浓度范围，用于控制不同发声任务间的通气变异。采用贝叶斯回归模型分析发声类型、气溶胶产生量与生理预测因子之间的关联。