These include the size and shape of the resonating cavities (pharynx, oral cavity, and nasal cavity), the position of the tongue, and the degree of mouth opening. The velopharyngeal (VP) valve plays an integral role in determining speech resonance however, other aspects of the vocal tract also contribute to the perceived sound. Perceived resonance is the result of this filtered tone. The vocal tract filters this sound, selectively enhancing harmonics based on the size and/or shape of the vocal tract. Speech resonance is the result of the transfer of sound produced by the vocal folds through the vocal tract comprised of the pharynx, oral cavity, and nasal cavity (Kummer, 2020a Peterson-Falzone, Trost-Cardamone, Karnell, & Hardin-Jones, 2017). See the Velopharyngeal Dysfunction Evidence Map for summaries of available research on this topic as it relates to resonance disorders. See ASHA's Practice Portal page on Voice Disorders. Resonance disorders should not be confused with conditions targeted by resonant voice therapy, an approach that emphasizes phonation with the least effort and impact on the vocal folds. Resonance disorders are not voice disorders, although they are often mislabeled as such. For a discussion of articulation disorders that may co-occur with VPD and resonance disorders, see ASHA's Practice Portal page on Cleft Lip and Palate. See Classification of Velopharyngeal Dysfunction.

Velopharyngeal dysfunction (VPD) is discussed in this page as it relates to resonance disorders. Resonance disorders-specifically hypernasality-are also discussed in ASHA's Practice Portal page on Cleft Lip and Palate as they relate to clefting. The scope of this page is resonance disorders in children and adults.

How to use resonance