An Acoustic Exploration of Female Voice Under Loading in Beijing's Winter Environment

This exploratory study examined whether female university students with different residence durations in Beijing differed in subjective voice symptoms, baseline acoustic characteristics, and acoustic responses to a laryngeal diadochokinesis vocal loading task (LDDK-VLT) in winter.

Forty-one nonsmoking female undergraduate students aged 18-21 years were recruited at Beijing Language and Culture University and divided into recent arrivals (n = 16), intermediate residents (n = 14), and local controls (n = 11). Acoustic recordings were obtained at baseline (t0), immediately after the LDDK-VLT (t1), and after a 15-minute quiet rest (t2). Measures included Maximum Phonation Time (MPT), Dysphonia Severity Index (DSI), Fundamental Frequency (F0), Intensity, Jitter, Shimmer, Harmonics-to-Noise Ratio (HNR), and Smoothed Cepstral Peak Prominence (CPPS). Participants completed the Voice Handicap Index-10 (VHI-10) and Vocal Fatigue Index (VFI) after all recordings. Group differences, acoustic change scores, questionnaire-acoustic associations, and longitudinal acoustic trajectories were analyzed.

Recent arrivals showed numerically higher VHI-10 and VFI Factor 1 scores than local controls, but no questionnaire or baseline acoustic measure differed significantly across groups after false discovery rate (FDR) correction. Change-score analyses showed an uncorrected group difference for post-rest Jitter (free speech) change, but this did not survive FDR correction. Linear mixed-effects models showed significant corrected time effects for MPT, DSI, Intensity (reading), Intensity (free speech), Shimmer (reading), CPPS (reading), and CPPS (free speech). No group main effect or Group × Time interaction remained significant after correction. Questionnaire-acoustic associations were exploratory and did not survive correction.

The LDDK-VLT elicited measurable time-dependent acoustic changes, whereas residence duration in Beijing did not significantly moderate longitudinal acoustic trajectories after correction. Descriptive patterns in subjective scores and selected acoustic changes suggest that residence duration may be relevant to voice status and recovery, but larger studies with direct environmental exposure assessment are needed.