CHARACTERISTICS OF VOCAL FOLD ADDUCTION RELATED TO VOICE ONSET

This study examined whether vocal fold kinematics prior to phonation d iffered between hard (glottal), normal, or breathy onsets in men and w omen. Glottal landmarks were identified and digitized from videotape r ecorded with a rigid laryngoscope during different voice onset types. Significant linear relationships (p less than or equal to 0.0055) were found among onset types on measures of (a) gesture duration when movi ng from 80% to 20% of maximum distance during adduction, (b) maximum v elocity, (c) duration between the completion of adduction and phonatio n onset, and (d) ratios of maximum velocity to maximum distance betwee n the vocal processes, an estimate of stiffness. The gesture duration was greatest for breathy onsets and least for hard onsets, while the m aximum velocity, latency between adduction and phonation onset, and es timated stiffness were greatest for hard onsets and least for breathy onsets. The results suggest that one trajectory seems to be used with increases in gesture duration being accompanied by decreases in articu lator stiffness when moving from hard to normal to breathy voice onset types.