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Patterns of nasalance in a sample of normal gerontologic subjects
Abstract:
The purpose of this investigation was to evaluate velopharyngeal adequacy in gerontologic subjects using an acoustic analysis strategy. Sixty normal older subjects (30 male, 30 female), ranging in age from 50 to 80, read three passages developed by Fletcher (1976) that differ in number of nasal sounds. In addition, all subjects sustained the vowel /a/. The speech samples were analyzed using TONAR II, which calculates the ratio of nasal sound pressure level to nasal + oral sound pressure level (nasalance). Tonagrams (plots of nasalance over time) were obtained from all subjects. Results demonstrated that older subjects generally evidenced abnormally high nasalance values for the Zoo Passage (contains no nasal sounds). In addition, females exhibited significantly higher nasalance values than males. Inspection of the tonagrams revealed three abnormal acoustic patterns: (1) pervasively high nasalance, (2) momentary loss of velar control, (3) progressive deterioration in velar control. These results are discussed with reference to known neuroanatomical changes associated with advancing age.

