We usually don’t think too much about talking, except when we physically cannot.
Then we croak, cough, try to clear our throats, and wait for whatever is wrong to go away. Usually problems resolve on their own. But sometimes people need help from a speech pathologist.
Almost all voice problems are caused by irregularities in the two flaps of muscle that provide humans with a way to hum, sing, speak and shout.
Mary Bellandese, assistant professor in the Center for Communication Disorders at Southern Connecticut State University, has seen most of the ways that vocal folds, or cords, can malfunction.
Some problems arise from overuse. Others are caused by tension. At this time of year many people with colds develop bronchitis and “lose’ their voices temporarily.
Acid reflux also impinges on speech, and diseases like Parkinson’s can make talking difficult. Traumatic brain injury, including stroke, are additional culprits.
“People take their voice and swallowing for granted until something goes wrong. Then they’re surprised,” Bellandese said.
“Many people are hoarse, or they don’t like the way they sound,” she said.
Why does screaming make voices scratchy? How does coughing cause silence?
The same way that over-exertion can cause sore muscles, or repetitive action can lead to inflammation, or how ill-fitting shoes generate calluses.
This is because the vocal cords (or folds, as speech pathologists call them) are a set of small muscles set in the larynx, directly in the path of incoming air and exhalation.
The cords are about one-inch long in men, and a little shorter in women, which is why females tend to have higher voices. The muscles also lose their resiliency as we age, hence the higher pitch of old age.
These little muscles generate everything from a concert hall-filling soprano to an intimate murmur.
Cords come in pairs, forming a human wind instrument.
Like any other muscle, they are connected to the body by ligaments. The cords are also covered by a layer of tissue that vibrates when air is forced between them. Vibrating cords makes exhaled air vibrate, creating sound.
Long ago, idle children would take two blades of grass, hold them parallel between thumbs and forefingers, and blow through them, producing an ear piercing screech.
That’s pretty much what the vocal cords do. However, we can control the timbre and pitch of our voices by relaxing or contracting the cord muscles.
If the muscles are tensed, the cords bunch up, and the pitch is higher. This is why people under duress often speak in a higher voice, Bellandese said. Relax the cords and the voice drops.
But if all men and women have vocal cords of about the same length, why doesn’t everyone sound the same?
For the same reason that woodwind and brass instruments need tubing and bells. Vibrations in the vocal cords resonate through the throat mouth and sinuses.
“Voice depends on the size and thickness of the vocal folds, and the way they vibrate. It also depends on air flow and how the muscles configure the vocal cords. Sound resonates in the oral cavity,” Bellandese said.
“We can modify any of these factors,” she said.
Otherwise, no two people have exactly the same phonetic plumbing.
One of the most common voice problems, excluding hoarseness from hacking, is muscle tension dysphonia, she said.
“Seven to 10 percent of Americans have it at any given time. It’s a little higher in the winter,” Bellandese said.
Muscle tension dysphonia seems to appear most commonly in teachers, lawyers and in others who spend a lot of time talking loudly, she said.
The muscles in these over-talkers bunch up into a gnarl, keeping the vocal cords slightly apart. The result is hoarseness, as extra air whooshes through the gap.
This also happens when the vocal cords become inflamed by coughing. The cords temporarily lose their flexibility and are unable to close sufficiently to vibrate.
Chronic inflammation can lead to formation of a callus, which leads to a bump on the cord called a vocal nodule. Voice therapy and rest is usually enough to send the nodule on its way. Sometimes surgery is necessary to remove the nodule.
Know someone who seems to scream rather than talk? She might have a nodule, or other lesion on her vocal cords. Squeezing the cords together helps, but then a burst of air is necessary to make a voice. The result can be a very loud talker.
Vocal cords can also become inflamed by errant stomach acid. If the muscles separating the stomach from the esophagus weaken, acid can gurgle up into the larynx. Medication or surgery is the solution.
Bellandese said the best strategy is to keep the voice healthy. “Learn to ‘warm up.’ Take care of your voice. This is especially important for teachers,” she said.
You may want to warm up in private. Generally, the idea is to limber up the muscles by humming from a low pitch to high, and from high to low, several times. Sustain certain notes, and perform trills. Stretch your neck and relax your facial muscles and tongue.
It’s also important to keep your vocal machinery well hydrated. Do not imbibe coffee or alcohol in excess, Bellandese said. Just drink a lot of water.
Smoking is bad for numerous reasons, and it’s also hard on the vocal folds. Avoid dust and mold, as well.
What about the current crop of bands led by vocalists who literally scream lyrics? Why don’t their vocal cords disintegrate?
“There are ways to make all sorts of sounds safely,” Bellandese said.
Professional screamers learn to, or are trained, to use “false vocal cords,” two flaps of tissue above the real cords, that otherwise do not vibrate, she said.
That way they can scream for hours without damaging the delicate cords.
Don’t try this at home unless you know what you’re doing, or do not mind the prospect of speaking in a permanently gravelly voice.