Objective: To examine the acoustic perturbation characteristics of sustained vowel /a/ production in native Mandarin speakers across the lifespan. The study focused on how age, sex, and pitch influence the relationships among fundamental frequency (F0), absolute jitter (Jita), and shimmer in dB (ShdB), aiming to reveal general patterns of phonatory stability in normal voices.
Methods: A total of 767 native Mandarin speakers (365 males, 402 females) as subject participated in this study. These subjects were categorized by sex and further divided into eight age groups for each sex: 3–6, 7–10, 11–15, 16–18, 19–30, 31–45, 46–60, and over 60 years. Each one pronounced two sustained vowels /a/ (2–3 seconds each) under five pitch conditions, yielding more than 7,900 valid voice samples.
Acoustic parameters (F0, Jita, and ShdB) were extracted using the Multi-Dimensional Voice Program (MDVP). Statistical analyses were performed in R (version 4.5.0). Group means and standard deviations were computed to describe acoustic distributions. Multiple linear regression models examined the main and interaction effects of F0, sex, and age. Pearson correlation analyses within each age–sex group assessed the relationships between F0,Jita, and ShdB。. Independent-sample t-tests compared Jita and ShdB across pitch conditions.
Results:Significant main effects of sex (p < 0.01) and age (p < 0.001) were observed, with a significant interaction between the two on the relationships between F0 and acoustic perturbations (p < 0.01). Across all age–sex groups, F0 was strongly and negatively correlated with Jita and ShdB (r < −0.85), except in females aged 16–18 years, where the correlation between F0 and ShdB was weaker (r = −0.70). Jita and ShdB values were significantly higher under the lowest pitch condition than under all other pitch conditions (p < 0.001).
Conclusion: From a lifespan and sex perspective, revealed the overall characteristics and variation patterns of Jita, and ShdB in sustained vowel production among native Mandarin speakers. Based on large-scale acoustic data, a quantitative reference framework for vocal perturbation in Mandarin was established, providing a valuable basis for voice function assessment, clinical diagnosis, and rehabilitation training.
Acknowledgments: This research was supported by the Major Program of the National Social Science Foundation of China ( Grant No. 22&ZD213).