Velopharyngeal function in young and older adult speakers: evidence from aerodynamic studies.

Intraoral air pressure (P0), nasal airflow, and nasal air volume characteristics were determined from 63 adults speakers during production of oral and nasal consonants. The speakers were categorized into two age groups. Young speakers (21 males, 21 females) ranged in age from 18 to 37 years (mean = 24); older speakers (10 males, 11 females) ranged in age from 68 to 83 years (mean = 75). Speakers produced the syllables /pi/ and /si/ and the word "hamper" at self-determined loudness levels during reiterant speech tasks. Results indicated similar velopharyngeal function between young and older adults as reflected by nasal airflow and air volume measures. Older adults, however, exhibited significantly higher levels of P0 than younger adults during production of /p/ in "hamper." In addition (a) male speakers exhibited higher P0 than females during production of /p/ in "hamper," (b) all speakers demonstrated declination of P0 during production of /p/ in "hamper" as a function of word position in the utterance, and (c) male and female speakers exhibited different patterns of nasal air volume during production of "hamper" as a function of word position in the utterance. The intraoral air pressure results suggest differences in respiratory function between young and older speakers. The nasal air volume results suggest a gender specific velopharyngeal declination effect. Implications for velar motor control strategies are discussed.