Effect of Varied Tube Phonation in Water Exercises on Nasometric and Electroglottographic parameters: Modification in Terms of Fluid Density and Tube Submerged Depth

Abstract

Within the scope of semi-occluded vocal tract exercises (SOVTEs), we aimed to examine the effects of four exercise combinations, which involved various fluid densities and tube submersion depths, on acoustic and electroglottographic (EGG) parameters. Four procedures (P) were applied consecutively to 30 female participants with normal voices using different tube submersion depths and fluid densities, including P1 (2 cm, water), P2 (2 cm, nectar), P3 (10 cm, water), and P4 (10 cm, nectar). Nasometric (Nasometer II model 6450) and EGG (Electroglottograph model 6103) measurements were taken before the procedures were initiated (pre-test) and at the end of each procedure. In addition, EGG measurements were taken for each procedure during the application. For all three velar positions (oral passage, oro-nasal passage, nasal passage), the only procedure that caused a significant change compared to the pre-test stage in regard to nasalance score was P2 (2 cm nectar) in common. All other procedures except P1 (2 cm water) significantly increased velar closure compared to pre-test levels. However, when the differences between the exercises were examined, the least velar closure, compared to the other procedures, was obtained after P4 (10 cm nectar). While there was no significant difference between the procedures in the EGG measurements during the exercise, a significantly higher tendency to contact was observed after the procedures with a denser consistency, and an increase in the fundamental frequency (fo) values occurred in the pairwise comparisons of the procedures in the measurements after the exercises. In SOVTEs in which water phonation is performed with a tube, the use of a fluid with a consistency denser than water can be considered a particularly promising approach. In addition, exercises performed with increasing consistencies in 2 cm depth can provide more vocal cord and velopharyngeal port closure by increasing EGG-CQ and nasalance score values. However, more care should be taken while increasing the consistency at a submersion depth of 10 cm.