A to Z: Resonance Disorder
May also be called: Hypernasality; Velopharyngeal Dysfunction; Velopharyngeal Incompetence; Velopharyngeal Insufficiency; Hyponasality; Cul-de-Sac Resonance; Velopharyngeal Inadequacy
A resonance (REZ-uh-nents) disorder is a speech disorder in which something changes the way air flows through the mouth when a person is talking.
More to Know
Resonance is a characteristic of the human voice. It's determined by the way sounds vibrate — or resonate — in the structures of the mouth, nose, and throat during speech.
The velopharyngeal (vee-low-fair-in-JEE-ul) valve separates the oral cavity (mouth) from the nasal cavity (nose). When we breathe, the velopharyngeal valve stays open. When we speak, the soft palate (the back part of the roof of the mouth) closes off the valve to direct air through the mouth.
A resonance disorder can happen if something obstructs the oral or nasal cavities and blocks regular airflow, or if the velopharyngeal valve doesn't work correctly. If the soft palate is shorter than normal or doesn't close the valve completely, too much sound may come from the nose during speech. If something is blocking the nasal cavity, such as during a bad cold, too little sound may come from the nose.
Resonance disorders are commonly associated with cleft palate, a birth defect in which there is an opening in the lip and/or palate. Other causes include swollen tonsils and neurological disorders.
Mild resonance disorders may be treated with speech therapy. Moderate to severe cases sometimes need surgery to correct problems with the velopharyngeal valve.
Keep in Mind
Kids with resonance disorders often benefit from speech therapy. If therapy alone doesn't help, a doctor can recommend other options. Surgery can usually fix structural defects, but kids with resonance disorders may still need speech therapy before and after their operations.
All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts.