THE LARYNX AND THE VOICE
The picture on the right of of the larynx, was taken from the top looking down into the trachea. The V-shaped structure is what we are looking at. This structure is made up of ligaments and muscles covered by mucous membranes. At rest, the ligaments are in a V-shape and air can pass uninterrupted up and down the trachea.
To create voice, these vocal folds (otherwise known as vocal cords) come together, totally closing off the airway. As we breathe out , the air from the lungs cannot get through the valve that has been formed. As the pressure builds up, a tiny amount of air can get through, then the cords close because of the dropped pressure. As we continue to breathe out, the pressure build up again, and the air can get through the valve. Then the pressure drops, the valve closes, and the cycle repeats itself over and over. This is how voice is made. The air is vibrating and it is this vibrating air that we hear as sound.
The air comes up into the nose and or mouth and the sounds of speech are made by what we do with that air...e.g. we stop it at the lips to make a /b/.
CHANGING THE VOICE
We can make our voices louder or softer by controlling how much air comes out , and with what degree of pressure. We can control the pitch of the voice by stretching the vocal cords for a high pitch or by shortening and thickening them to produce a low pitched sound. We can change the quality of the voice e.g. a 'sad' voice, a whinge, a growling voice, a booming voice and so on.
Some voices are gorgeous ... like that of the man who says, "This is CNN"; others are irritating... like Donald Duck's voice.
There is a huge variability in what makes a voice 'normal'. Some men have low voices; others less low.
Voices change with age. Little children have higher pitched voices than older children. Voices change at puberty. Some teenage boys have squeaky voices that then break ... this happens as the body grows and changes and the vocal folds thicken. Older people have voice changes too - the tone of the muscles changes, strength is diminished and so the voice can change too.
Swelling associated with inflammation and laryngitis makes the vocal fold thicker, heavier and stiffer. The vocal pitch will lower because the folds are thicker and the increased stiffness causes irregular and inconsistent vocal vibrations. Perceptually the voice will be heard as rough and breathy in quality.
NODULES AND POLYPS
A vocal cord nodule is a small, inflammatory or fibrous growth that develops on the vocal cords." A nodule is a growth of the epithelium that covers the mucous membrane. Nodules look like callouses. As a result, the edge of the vocal cord is uneven and so when the vocal cords come together to form voice, the quality of the voice is affected, and there is air escape and hoarseness or huskiness.
A vocal cord polyp is a small swelling in the mucous membranes covering the vocal cords. As they grow, they take on a rounded shape. They may run the whole length of the vocal cords or be localized.
ASHA's states, "Polyps can take a number of forms. They are sometimes caused by vocal abuse. Polyps appear on either one or both of the vocal cords. They appear as a swelling or bump (like a nodule), a stalk-like growth, or a blister-like lesion. Most polyps are larger than nodules and may be called by other names, such as polypoid degeneration or Reinke's edema."
Causes of nodules and polyps
Some of the time, the nodules are caused by using the voice in ways that stress the anatomical structures such as
talking too loudly
Some people are at risk from their occupations
people who work in noisy environments
Sometimes, anxiety and tension influence the voice.
Medical conditions can influence the health of the larynx such as GERD (reflux) and allergies. People who cough a lot can hurt their vocal folds.
Smoking irritates the larynx. A lot.
Coffee can be dehydrating.
How does the voice sound when there are nodules or polyps?
People can have pain when speaking and/or earache
Treatment of nodules and polyps
The last option is surgery. We usually try to change the way you speak.
SPEECH THERAPY AND VOICE PROBLEMS
Speech therapists are trained to work with people who have problems with voice. We work in consultation with medical personnel such as ear, nose and throat surgeons (ENTs). Some speech therapists have access to technology that assists with voice therapy, but it is not always available and is not always essential to therapy.
The larynx is a complex structure that produces voice.
Please note that all voice problems should be evaluated by and ear, nose and throat surgeon before they are addressed by a speech therapist.
Speech therapists in South Africa are not allowed to use instrumentation to look down your throat into your larynx.