Objective:
This study takes native Mandarin speakers across the lifespan as the research object, explores the impact of different vowels on voice jitter, and systematically examines the differences in voice perturbation among different ages and genders. Specifically, the research focuses on the differences in voice perturbation among four sound samples /a/, /i/, /u/, and /m/as well as their internal correlations, aiming to explain the basic characteristics and variation patterns of voice jitter for different vowels across the lifespan and genders in Mandarin.
Methods:
The participants of this study were 767 native Mandarin speakers (365 males and 402 females), who were divided into eight age groups: 3–6, 7–10, 11–15, 16–18, 19–30, 31–45, 46–60, and over 60 years old. All participants were in good health with no voice disorders. For data collection, participants were asked to produce the sustained vowels /a/, /i/, and /u/ twice each at a comfortable pitch and loudness; meanwhile, they were also asked to produce the nasal /m/ twice each as a reference, with each production lasting approximately 2–3 seconds.
The recording equipment included a SHURE BETA 54 headworn microphone, a Creative Sound Blaster X-Fi Surround 5.1 Pro sound card. Cool Edit Pro 2.0 was used to monitor the amplitude in real time (ensuring it did not exceed 80% of the maximum quantization value), with a quantization precision of 16 bits and a sampling rate of 44.1 kHz. For acoustic measurement, all voice parameters were extracted using the Multi-Dimensional Voice Program (MDVP, Model 5105), including five parameters: Jita, Jitt, ShdB, Shim and Pitch. After normalizing the results, the mean and variance were calculated. Subsequently, the results of voice parameters for four sounds were analyzed by genders and eight age groups.
Results:
The research results showed that: F0 was higher in younger age groups, regardless of vowel quality; For the vowel /i/, Jita and Jitt exhibited generally significant differences compared with the vowels /a/, /u/ and the nasal /m/ across all age groups (p<0.05), and such differences were more prominent in females than in males, with Jitt showing the most differences in the three youngest age groups; For the vowel /a/, ShdB and Shim presented significant differences compared with the vowel /u/ and the nasal /m/ (p<0.05), while no significant difference was observed between /a/ and /i/; For the vowel /i/, ShdB displayed significant differences compared with /u/ and /m/ in the first five age groups (p<0.05), and Shim showed significant differences compared with /u/ and /m/ in the first three age groups (p<0.05); No significant differences were found in the voice jitter parameters of /u/ and /m/ when compared with other sounds.
Conclusion:
This study reveals the overall characteristics and differences of frequency perturbation and amplitude perturbation in vowels and nasals of Mandarin, as well as the effects of gender and age variables, provides a reference basis for voice function assessment.
Acknowledgments: This research was supported by the Major Program of the National Social Science Foundation of China: Grant No. 22&ZD213.