Laryngeal airway resistance of older men and women as a function of vocal sound pressure level.

This study examined laryngeal airway resistance (RLAW) in 10 healthy male and 10 female subjects within three age groups (55:0-64:11; 65:0-74:11; and 75:0+ years). A noninvasive procedure (Smitheran & Hixon, 1981) was employed to investigate RLAW at four vocal sound pressure levels (SPL) (25th, 50th, 75th percentiles of the SPL range, and comfortable voice level [CV]), RLAW values for the oldest group of females were found to be higher at each SPL percentile than those of the two younger age groups. The oldest group of males differed from the youngest group of males in RLAW values only at the 75th percentile level of SPL. Laryngeal airway resistance values were higher for females than males. As a group, the females generally had transglottal airflow that increased or remained relatively steady, whereas males maintained more linear changes in transglottal airflow and transglottal pressure as relative SPL increased. The present results suggest that separate norms need to be employed for males and females when determining RLAW values. Further, consideration should be given to examining the underlying airflow and pressure values when evaluating or monitoring changes in aerodynamic activity during voice production.