Nasometry refers to measurement of the modulation of the area of the velopharyngeal opening, using movements of the

velum Velum may refer to: Human anatomy * Superior medullary velum, anterior medullary velum or valve of Vieussens, white matter, in the brain, which stretches between the superior cerebellar peduncles ** Frenulum of superior medullary velum, a sligh ...

and pharyngeal walls, in speech and singing. The velopharyngeal opening connects the oral air passageway with the nasal air passageway. The size of this velopharyngeal opening generally controls the nasality of the resulting speech or singing. The term nasometry is generally used to refer to non-invasive techniques for measuring the size of the opening, as opposed to

endoscopic An endoscopy is a procedure used in medicine to look inside the body. The endoscopy procedure uses an endoscope to examine the interior of a hollow organ or cavity of the body. Unlike many other medical imaging techniques, endoscopes are insert ...

or other visual methods. During

vowel A vowel is a syllabic speech sound pronounced without any stricture in the vocal tract. Vowels are one of the two principal classes of speech sounds, the other being the consonant. Vowels vary in quality, in loudness and also in quantity (leng ...

sounds, nasometry usually refers to the use of a system for measuring

nasalance Nasalance is a measure of the degree of velopharyngeal opening in voiced speech formed by computing the ratio of the amplitude of the acoustic energy at the nares, An, to amplitude of the acoustic energy at the mouth, Am. The term ''nasalance'' us ...

. During

consonants In articulatory phonetics, a consonant is a speech sound that is articulated with complete or partial closure of the vocal tract. Examples are and pronounced with the lips; and pronounced with the front of the tongue; and pronounced wit ...

, Nasometry usually refers to the measurement of air escaping past the velum and escaping through the nose. This escaping air is referred to as

nasal emission Nasal emission is the abnormal passing of oral air through a cleft palate, or from some other type of velopharyngeal inadequacy (VPI), during the production of a consonant that requires a buildup of oral air pressure for proper pronunciation, such ...

.R.J. Baken, Robert F. Orlikoff. ''Clinical Measurement of Speech and Voice'' San Diego: Singular, 2000 Thus, a complete system for nasometry consists of a combined nasalance measurement system and nasal emission measurement system. However, when one or another of these variables is not important, the term nasometry can be used to refer to either measurement of nasalance or nasal emission.

References

Phonetics Human voice

See also

References