The voice is produced as air from the lungs moves up through and vibrates the vocal cords. This is called phonation. The voice is then changed as it travels up through the different-shaped spaces of the throat, nose, and mouth. This is called resonance. Voice disorders include both phonation and resonance disorders:
The voice may be harsh, hoarse, raspy, cut in and out, or show sudden changes in pitch with phonation disorders. Voice disorders can be due to vocal nodules, papillomas, ulceration, a laryngeal web, paralysis or weakness of the vocal cords, or difficulty timing breathing for speech.
These are caused by an imbalance in sound energy as the voice passes through the spaces of the throat, nose, or mouth. When parents report that their child’s voice sounds “nasal” they are usually hearing one of two different types of resonance disorder:
- Hyponasality (or denasality): This is when not enough voice energy comes through the nose, making the child sound “stopped up.” This might be caused by some blockage in the nose, or by allergies.
- Hypernasality: This happens when the movable, soft part of the palate (the velum) does not completely close off the nose from the back of the throat during speech. Because of this, too much sound energy escapes through the nose. This can be due to a history of cleft palate, a submucous cleft, a short palate, a wide nasopharynx, the removal of too much tissue during an adenoidectomy, or poor movement of the soft palate.
Reasons for Concern
- If the voice is hoarse, harsh, breathy, or of poor quality
- If the voice is always too loud or too soft
- If the voice is too high or too low for the child's age or sex
- If the voice often breaks or suddenly changes pitch
- If the voice sounds hyponasal or hypernasal