Why do people's voices lower as they age?

June 30, 2006 2:39 AM

Why do people's voices lower as they age?

I understand that various vices -- smoking, drinking -- can produce a lower tone. But do the vocal chords shorten over time? Is there a physical change that occurs causing a tonal shift to someone's voice over time?

posted by Ms Snit to science & nature (10 comments total)

If vocal cords shortened, your voice would get higher - think of a guitar.

Your chords must lengthen and/or be stretched less tightly... but I don't know which.
posted by cogat at 3:31 AM on June 30, 2006

Generally when I am wondering about physical changes to the body I search for the change and add "physiology" in. With this search, the 4th result says:

Growth may double the length of the vocal cords in the male adolescent; hence his dramatic "change of voice."
posted by jwells at 4:53 AM on June 30, 2006

Not sure I agree with the premise. Listen to Jack Welch and John Fogarty, then and now. Decline in testoterone, I read somewhere.
posted by IndigoJones at 5:22 AM on June 30, 2006

Women's voices get lower with age, but what I've always seen is male voices getting higher. I always thought it was due to hormonal changes.

This is rotten formatting, but search for "Changes with age" on that page.
posted by booksandlibretti at 6:06 AM on June 30, 2006

Not that anyone asked for it, but here is the physics of the whole 'looser vocal cords = lower voice':

f = v/2L where v is the speed of sound through air (about 300 m/s), L is the length of string (or in this case, vocal cord) and f is the frequency (pitch). This is similar to a guitar. When you press down on a fret on a guitar (shortening it) it has a higher note.
posted by Serial Killer Slumber Party at 6:10 AM on June 30, 2006

As with other tissues in the body, vocal cords lose volume and grow less supple with age. Thus they vibrate more slowly.

Another aggravating cause is the reduction in what voice teachers call "breath pressure." Less air moving through the cords over a given time results in slower vibration and thus lower pitch.

Some ENT practices are now offering "voice lift" surgery, a procedure to plump up the vocal cords with fat, collagen or Gore-Tex, promising a more youthful vocal timbre.
posted by La Cieca at 7:34 AM on June 30, 2006

A second point here is that older voices are generally weaker and less resonant (for the same reasons I mentioned above) and so speakers tend to use chest voice to make themselves heard. The vocal position for chest voice works most optimally at lower pitches. And so, essentially, the speaker is choosing to speak on low notes because those are his loudest notes. (Or I should say "her" because this particular shift of modal pitch is more obvious in women's voices.)
posted by La Cieca at 7:43 AM on June 30, 2006

Heck, just listen to William Shatner as Capt. Kirk and as Denny Crane. A world of difference. How come?
posted by madman at 11:25 AM on June 30, 2006

I think that it is not only a matter of older vocal cords becoming stiffer, but of supporting structures in the larynx and pharynx also becoming less pliable, and of the soft palate drooping with age. The youthful voice contains a far higher percentage of harmonic energy over the fundemental than does the older voice, and these higher frequencies are more readily projected and transmitted by younger throats and palates. Then too, many older folks have accumulated some fat about the neck (wattle, double chins, etc.) and have sagging lower jaws, all of which also effectively dampen higher frequency energy.

It's kind of like playing a pipe organ, where, gradually, the top ranks become encrusted by bat guano from the belfry... Eventually, all you've got left are the pedal notes from the big pipes, and the wheezing of the compressor.
posted by paulsc at 12:06 PM on June 30, 2006

Thank you all... a lot of good info/quesstimates abound.
posted by Ms Snit at 9:48 AM on July 3, 2006