COMPARISON OF AERODYNAMIC AND ELECTROGLOTTOGRAPHIC PARAMETERS IN EVALUATING CLINICALLY RELEVANT VOICING PATTERNS

The purpose of the present study was to identify one or more aerodynam ic or electroglottographic measures that distinguish among voicing pat terns that are clinically relevant for nodule pathogenesis and regress ion: a presumably pathogenic pattern (pressed voice), a neutral patter n (normal voice), and two presumably therapeutic patterns (resonant vo ice and breathy voice). Trained subjects with normal voices produced s everal tokens of each voice type on sustained vowels /a/, /i/, and /u/ . For each token, maximum flow declination rate, alternating current f low, and minimum flow were obtained from inverse-filtered airflow sign als, and closed quotient and closing time were obtained from electrogl ottographic signals. The results indicate that for /a/ and /i/ (but no t for /u/), the closed quotient provides a sensitive tool for distingu ishing the voice types in physiologically interpretable directions. Fu rther, post-hoc analyses confirmed a direct relationship between the d osed quotient and videoscopic ratings of laryngeal adduction, which pr evious work links to nodule pathogenesis and regression.