How do we produce voice?
The sound of your voice is affected by the size and shape of your larynx, throat and mouth. Abnormalities in the size and shape of these structures or with the airway (trachea) can affect voice quality. Voice problems can be the result of trauma as well.
To produce voice, air is drawn into the lungs, usually through the nose. The lungs expand when they fill with air, and then we gradually release the air through the trachea and mouth. We control the flow of air with muscles of the diaphragm, ribcage and larynx (voice box). As air passes through the trachea, it passes between the vocal folds. Just after we breathe air in, muscles in the larynx close the vocal folds to help keep the air in the lungs. As air pressure builds, the air pushes against the vocal folds, causing them to open. The interaction of muscle tension (closing the vocal folds) and air pressure (opening the vocal folds) causes a vibration of the vocal folds. This vibration creates sound. That sound is shaped by the size and shape of our vocal folds, throat (pharynx) and mouth.
Phonation refers to the production of voice. Each person’s voice is unique to him or her. Our voices are as identifiable as a fingerprint. The first voiced sound we often hear from an infant is a cry. Generally, in infancy, cries can be differentiated and parents learn the meanings of different cries for hunger, pain/discomfort, etc. As infants grow, they begin to coo, exploring the use of their voices and learning what sounds they can make. Eventually, by listening to others and decoding the language around them, they begin to shape their voices by producing various vowels and consonants that initially make up babble and “baby-talk” and later become real words. Find our speech development chart for children ages 0-5 years here.
What are some common voice problems?
There are certain voice problems associated with congenital problems with the airway or central nervous system. Other voice problems are associated with the structures of the mouth, nose and other structures in the throat such as tonsils and adenoids. Still other voice problems are the result of misuse of the voice.
When the airway is compromised or obstructed, a child may not be able to produce voice (phonate). Oftentimes, these problems require surgery. This is also true of problems with the larynx itself. Vocal fold paralysis accounts for 10 percent of all laryngeal problems. One or both vocal folds can be paralyzed. This paralysis is typically the result of damage or lesion to the nerves that stimulate the muscles of the larynx to move and is considered a problem of the central nervous system. Unilateral (one-sided) vocal fold paralysis can sometimes be managed with surgery. There are also devices that can be used to generate sound when the vocal folds cannot.
Children sometimes develop problems with voice without any type of physical or neurological problems. Like adults, children can develop vocal nodules (small bumps on the vocal folds) that make the voice hoarse or breathy. Misusing the voice by talking in an unnatural manner, screaming harshly or making certain noises such as truck and car sounds can lead to changes in voice quality. This in turn can affect how easy or difficult it is to understand what the child says.