Glottal closure, transglottal airflow, and voice quality in healthy middle-aged women

Seventeen healthy women, 45 to 61 years old, were examined using videofiberstroboscopy during phonation at three loudness levels. Two phoniatricians evaluated glottal closure using category and ratio scales. Transglottal airflow was studied by inverse filtering of the oral airflow signal recorded in a flow mask (Glottal Enterprises System) during the spoken phrase /ba:pa:pa:pa:p/ at three loudness levels. Subglottal pressure was estimated from the intraoral pressure during p occlusion. Running speech and the repeated /pa:/ syllables were perceptually evaluated by three speech pathologists regarding breathiness, hypo-, and hyperfunction, using continuous scales. Incomplete glottal closure was found in 35 of 46 phonations (76%). The degree of glottal closure increased significantly with raised loudness. Half of the women closed the glottis completely during loud phonation. Posterior glottal chink (PGC) was the most common gap configuration and was found in 28 of 46 phonations (61%). One third of the PGCs were in the cartilaginous glottis (PGCc) only. Two thirds extended into the membranous portion (PGCm); most of these occurred during soft phonation. Peak flow, peak-to-peak (AC) flow, and the maximum rate of change for the flow in the closing phase increased significantly with raised loudness. Minimum flow decreased significantly from normal to loud voice. Breathiness decreased with increased loudness. The results suggest that the incomplete closure patterns PGCc and PGCm during soft phonation ought primarily to be regarded as normal for Swedish women in this age group.