Why does your voice change as you get older? - Shaylin A. Schundler

In the mid-16th century, 00:08 Italians were captivated by a type of male singer 00:11 whose incredible range contained notes 00:14 previously thought impossible for adult men.s='mceAudioTime'>[:] 00:17 However, this gift came at a high price. 00:19 To prevent their voices from breaking, 00:22 these singers had been castrated before puberty, 00:25 halting the hormonal processes that would deepen their voices. 00:28 Known as castrati, their light, angelic voices were renowned throughout Europe, 00:33 until the cruel procedure that created them was outlawed in the 1800s.ass='mceAudioTime'>[:] 00:39 Though stunting vocal growth can produce an extraordinary musical range, 00:43 naturally developing voices are already capable of incredible variety. 00:48 And as we age, our bodies undergo two major changes which explore that range. 00:54 So how exactly does our voice box work, and what causes these shifts in speech? 01:00 The specific sound of a speaking voice is the result of many anatomical variables, 01:05 but it's mostly determined by the age and health of our vocal cords 01:09 and the size of our larynxes. 01:12 The larynx is a complex system of muscle and cartilage 01:16 that supports and moves the vocal cords, 01:18 or, as they're more accurately known, the vocal folds. 01:22 Strung between the thyroid and arytenoid cartilages, 01:25 these two muscles form an elastic curtain that opens and shuts across the trachea, 01:31 the tube that carries air through the throat. 01:34 The folds are apart when we're breathing, 01:36 but when we speak, they slam shut. [:] AudioTime'>[:] 01:39 Our lungs push air against the closed folds, 01:42 blowing them open and vibrating the tissue to produce sound. 01:46 Unlike the deliberate focus required for playing an external instrument, 01:50 we effortlessly change notes as we speak.<span class='mceAudioTime'>[:] 01:53 By pushing air faster or slower, 01:55 we change the frequency and amplitude of these vibrations, 01:58 which respectively translate to the pitch and volume of our voices. 02:03 Rapid and small vibrations create high-pitched, quiet tones, 02:07 while slow, large vibrations produce deep, bellowing rumbles. 02:12 Finally, by moving the laryngeal muscles between the cartilages, 02:16 we can stretch and contract those folds 02:19 to intuitively play our internal instruments. 02:22 This process is the same from your first words to your last, 02:26 but as you age, your larynx ages too. 02:29 During puberty, the first major shift starts, 02:32 as your voice begins to deepen. 02:35 This happens when your larynx grows in size, 02:38 elongating the vocal folds and opening up more room for them to vibrate. 02:43 These longer folds have slower, larger vibrations, 02:47 which result in a lower baseline pitch. [:] eAudioTime'>[:] 02:50 This growth is especially dramatic in many males, 02:53 whose high testosterone levels lead first to voice cracks, 02:57 and then to deeper, more booming voices, 03:00 and laryngeal protrusions called Adam's apples. [:] dioTime'>[:] 03:04 Another vocal development during puberty 03:06 occurs when the homogenous tissue covering the folds 03:09 specializes into three distinct functional layers: 03:13 a central muscle, 03:15 a layer of stiff collagen wrapped in stretchy elastin fibers, 03:19 and an outer layer of mucus membrane. 03:23 These layers add nuance and depth to the voice, 03:25 giving it a distinct timbre that sets it apart from its pre-pubescent tones.<span class='mceAudioTime'>[:] 03:30 After puberty, most people's voices remain more or less the same 03:35 for about 50 years. 03:37 But we all use our voices differently, 03:39 and eventually we experience the symptoms associated with aging larynxes, 03:44 known as presbyphonia. 03:45 First, the collagen in our folds stiffens 03:48 and the surrounding elastin fibers atrophy and decay. 03:52 This decreased flexibility increases the pitch of older voices. 03:57 But for people who have experienced the hormonal effects of menopause, 04:01 the higher pitch is countered and outweighed by swollen vocal folds. 04:06 The folds' increased mass slows their vibrations, resulting in deeper voices. 04:13 All these symptoms are further complicated 04:15 by having fewer healthy laryngeal nerve endings, 04:18 which reduces precise muscle control and causes breathy or rough voices. 04:23 Ultimately, these anatomical changes are just a few of the factors 04:28 that can affect your voice. 04:30 But when kept in good condition, 04:31 your voice box is a finely tuned instrument, 04:34 capable of operatic arias, 04:36 moody monologues, 04:38 and stirring speeches.