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Acoustic characteristics of voice in different cycles of life: an integrative literature review

ABSTRACT Purpose: to carry out an integrative literature review about the acoustic characteristics of healthy voice production, from childhood to old age. Methods: a bibliographic survey was conducted on the databases PubMed, SciELO, MEDLINE and LILACS, covering the last 10 years. Nineteen studies were found, meeting the proposed criteria, on acoustic measurements: F0 (fundamental frequency), jitter, shimmer and/or noise measurements, in males and females, with normal voices in their different stages of life. Results: the analysis showed that F0 is the most changing acoustic parameter as people grow up and grow old. Its values present gradual fall from childhood to old age in the female population, whereas among men such decrease lasts until adulthood. Jitter, shimmer and noise remain stable throughout childhood and adulthood, while shimmer and noise measurements increase in old age. In the literature, there is no consensus regarding increase of jitter measurements in the elderly. Conclusion: from childhood to old age, in both genders, vocal changes take place which are reflected, especially by F0. There is a scarcity of information on acoustics related to specific populations with ample age range, using the same methodology. The information in this study may guide future investigations aiming to understand natural changes occurring in the human voice, in addition to guiding in the clinical practice.