madman
Super Moderator
Abstract
The aim of the present literature review is to describe the influence of sex hormones on the human voice in physiological conditions. As a secondary sexual organ, the larynx is affected by sex hormones and may change considerably over the lifespan. In the current review, sex hormone-related voice modifications occurring during childhood, puberty, the menstrual cycle, pregnancy, and senescence are described. The roles of sex hormones (including gonadotropins, testosterone, estrogen, androstenedione, dehydroepiandrosterone, and dehydroepiandrosterone-sulfate) underlying physiological voice changes are discussed, the main differences between males and females are explained and clinical implications are taken into account.
Introduction
The voice is one of the most complex and finely developed of human functions, is not only fundamental for social interaction and communication but also for self-recognition and gender identification.
*The voice is produced through the interaction of the lungs, the vocal folds, and the vocal tract. Functionally, the lungs represent the power supply, while the vocal folds (an oscillator) work as the sound source and the vocal tract acts as an active resonator. Subglottal pressure is primarily responsible for sound pressure level (SPL) perceived as sound intensity. The vibrating vocal folds, by rapidly oscillating and rhythmically contacting each other, generate a fundamental frequency (F0) perceived as sound pitch. Through the vocal tract, the glottal sound is articulated and selectively amplified, obtaining a unique voice timbre [1].
Hormones have a major influence on the voice organ, affecting both the larynx itself and the structures of the vocal tract. Both in physiological conditions and in the case of endocrine disorders, the human voice can be strongly affected with consistent modifications [2]. The larynx, like a secondary sexual organ, is also considerably influenced by sex hormones.
The purpose of the present literature review is to collect and discuss present knowledge about the influence of sex hormones on the human voice from childhood to senescence, both in males and in females.
Elements of voice physiology
*Childhood
Sex hormones play an important role from the first period after birth during which a postnatal surge of gonadotropins and sex hormones is observed. This phase is called “mini puberty” because of its similarity to the pubertal period [5, 6]. During “mini-puberty”, boys have higher concentrations of circulating testosterone (T) while girls have higher levels of bioavailable estradiol (E2) [7].
*Puberty
Puberty is a crucial period of life during which dramatic physiologic and psychological changes take place. The onset of puberty is preceded by the phenomenon of adrenarche characterized by an increase of androgen secretion by the adrenal glands. The adrenal androgens include dehydroepiandrosterone (DHEA), dehydroepiandrosterone-sulfate (DHEAS), and androstenedione. Adrenarche is involved in the appearance of body odor and axillary and pubic hair. At puberty, the reactivation of the hypothalamic gonadostat and the secretion of gonadotropin releasing-hormone (GnRH) is responsible for gonadotropin secretion (follicle-stimulating hormone (FSH) and luteinizing hormone (LH)) by the pituitary gland, which stimulates the testis and the ovary production of T and E2, respectively. Clinically, the first physiological changes during puberty are the appearance of secondary sex characteristics, in particular, testicular enlargement in males and breast development in females [13].
With puberty, significant sex-related modifications of the voice organ take place, with enlargement and elongation of the larynx, the vocal tract, and the vocal folds. Males experience more dramatic changes than females, reaching a mean vocal fold length of 1.6 cm compared to a mean length of 1.0 cm in females and a mean vocal tract length of 16.9 cm compared to 14.1 cm in females. This difference can be explained by the so-called secondary descent of the larynx, a male-specific secondary sexual feature occurring during puberty [12]. Newman et al. found androgen receptors both in the cytoplasm and in the nucleus of the vocal fold cells in males. Testosterone is thought to target these receptors during puberty, this resulting in significant elongation and thickening of the vocal folds in males [14].
Functionally, during puberty, voice mutation takes place. With the mutation, voice pitch (F0) drops by about one octave in males, while the F0 of the female voice drops by about 3–4 semitones (Table 1). A parallel change of the vocal range is observed. Voice mutation occurs at a mean age of 12; in males, when testicular growth reaches 20 ml (Tanner stage G5), the mutation will start in less than a year. During voice mutation three main stages are observed, as follows [15]:
– Pre-mutation period: voice quality becomes flat and occasionally hoarse and breathy.
– Proper mutational period: uncertain intonation, sudden alterations in pitch, and falsetto-shifts.
– Post-mutational period: gradual maturation of the voice quality, reaching the typical adult voice timbre and range.
*Menstrual cycle
*Pregnancy
*Senescence
Conclusions
The human voice is strongly influenced by sex hormones throughout the lifespan, from childhood to senescence. As a secondary sexual characteristic, voice is deeply affected by sex hormone modifications, with substantial gender differences. The voices of males and females follow a divergent trajectory, reaching their maximum divergence during adolescence and tending to converge again with the aging process.
Vocal changes follow the physiological body modifications during life and reflect the hormonal well-being of a subject, in particular during critical transition processes. Clinicians should pay particular attention to their patients’ voice quality since it mirrors hormonal physiology and can therefore also be a marker of endocrine disorders, with significant implications for physical and psychological health.
The aim of the present literature review is to describe the influence of sex hormones on the human voice in physiological conditions. As a secondary sexual organ, the larynx is affected by sex hormones and may change considerably over the lifespan. In the current review, sex hormone-related voice modifications occurring during childhood, puberty, the menstrual cycle, pregnancy, and senescence are described. The roles of sex hormones (including gonadotropins, testosterone, estrogen, androstenedione, dehydroepiandrosterone, and dehydroepiandrosterone-sulfate) underlying physiological voice changes are discussed, the main differences between males and females are explained and clinical implications are taken into account.
Introduction
The voice is one of the most complex and finely developed of human functions, is not only fundamental for social interaction and communication but also for self-recognition and gender identification.
*The voice is produced through the interaction of the lungs, the vocal folds, and the vocal tract. Functionally, the lungs represent the power supply, while the vocal folds (an oscillator) work as the sound source and the vocal tract acts as an active resonator. Subglottal pressure is primarily responsible for sound pressure level (SPL) perceived as sound intensity. The vibrating vocal folds, by rapidly oscillating and rhythmically contacting each other, generate a fundamental frequency (F0) perceived as sound pitch. Through the vocal tract, the glottal sound is articulated and selectively amplified, obtaining a unique voice timbre [1].
Hormones have a major influence on the voice organ, affecting both the larynx itself and the structures of the vocal tract. Both in physiological conditions and in the case of endocrine disorders, the human voice can be strongly affected with consistent modifications [2]. The larynx, like a secondary sexual organ, is also considerably influenced by sex hormones.
The purpose of the present literature review is to collect and discuss present knowledge about the influence of sex hormones on the human voice from childhood to senescence, both in males and in females.
Elements of voice physiology
*Childhood
Sex hormones play an important role from the first period after birth during which a postnatal surge of gonadotropins and sex hormones is observed. This phase is called “mini puberty” because of its similarity to the pubertal period [5, 6]. During “mini-puberty”, boys have higher concentrations of circulating testosterone (T) while girls have higher levels of bioavailable estradiol (E2) [7].
*Puberty
Puberty is a crucial period of life during which dramatic physiologic and psychological changes take place. The onset of puberty is preceded by the phenomenon of adrenarche characterized by an increase of androgen secretion by the adrenal glands. The adrenal androgens include dehydroepiandrosterone (DHEA), dehydroepiandrosterone-sulfate (DHEAS), and androstenedione. Adrenarche is involved in the appearance of body odor and axillary and pubic hair. At puberty, the reactivation of the hypothalamic gonadostat and the secretion of gonadotropin releasing-hormone (GnRH) is responsible for gonadotropin secretion (follicle-stimulating hormone (FSH) and luteinizing hormone (LH)) by the pituitary gland, which stimulates the testis and the ovary production of T and E2, respectively. Clinically, the first physiological changes during puberty are the appearance of secondary sex characteristics, in particular, testicular enlargement in males and breast development in females [13].
With puberty, significant sex-related modifications of the voice organ take place, with enlargement and elongation of the larynx, the vocal tract, and the vocal folds. Males experience more dramatic changes than females, reaching a mean vocal fold length of 1.6 cm compared to a mean length of 1.0 cm in females and a mean vocal tract length of 16.9 cm compared to 14.1 cm in females. This difference can be explained by the so-called secondary descent of the larynx, a male-specific secondary sexual feature occurring during puberty [12]. Newman et al. found androgen receptors both in the cytoplasm and in the nucleus of the vocal fold cells in males. Testosterone is thought to target these receptors during puberty, this resulting in significant elongation and thickening of the vocal folds in males [14].
Functionally, during puberty, voice mutation takes place. With the mutation, voice pitch (F0) drops by about one octave in males, while the F0 of the female voice drops by about 3–4 semitones (Table 1). A parallel change of the vocal range is observed. Voice mutation occurs at a mean age of 12; in males, when testicular growth reaches 20 ml (Tanner stage G5), the mutation will start in less than a year. During voice mutation three main stages are observed, as follows [15]:
– Pre-mutation period: voice quality becomes flat and occasionally hoarse and breathy.
– Proper mutational period: uncertain intonation, sudden alterations in pitch, and falsetto-shifts.
– Post-mutational period: gradual maturation of the voice quality, reaching the typical adult voice timbre and range.
*Menstrual cycle
*Pregnancy
*Senescence
Conclusions
The human voice is strongly influenced by sex hormones throughout the lifespan, from childhood to senescence. As a secondary sexual characteristic, voice is deeply affected by sex hormone modifications, with substantial gender differences. The voices of males and females follow a divergent trajectory, reaching their maximum divergence during adolescence and tending to converge again with the aging process.
Vocal changes follow the physiological body modifications during life and reflect the hormonal well-being of a subject, in particular during critical transition processes. Clinicians should pay particular attention to their patients’ voice quality since it mirrors hormonal physiology and can therefore also be a marker of endocrine disorders, with significant implications for physical and psychological health.
