Nasal Resistance (NR) Technique: A Novel Approach to Improve Glottal Adduction.

OBJECTIVE

Several techniques have been practiced in the field of voice therapy to balance glottal pressures and improve glottal adduction. As such, Semioccluded Vocal Tract Exercises using narrow diameter straws have shown promise as a technique to increase glottal contact as reflected by Closed Quotients (CQ) measured from electroglottograph (EGG). This study explored the effect of nasal resistance (NR) technique, a manually induced NR approach, on glottal adduction in phononormal subjects as a possible new therapeutic technique to assist in glottal closure.

SUBJECTS: Thirty-four vocally healthy adult females qualified for this study. All subjects were reportedly and perceptually normal.

METHODS

Subjects were instructed to perform tasks including (a) steady modal phonation, (b) straw phonation, (c) humming, and (d) NR technique in a random order. EGG measures included calculation of the CQ and jitter during the mid-section of each stimuli for a minimum of 10 EGG cycles. One-way repeated measures ANOVAs and Bonferroni post-hoc comparisons were calculated to determine differences between each phonatory task for the outcome measures of CQ and jitter.

RESULTS

Analyses revealed that the mean CQ was significantly different in all the tasks performed with humming (33.99%) at the lowest and NR technique at highest (43.88%). Though the CQ of straw phonation (40.53%) was higher than modal steady phonation (36.65%), jitter was found to be significantly lower for NR technique (0.23%). Jitter during straw phonation (0.43%) did not differ significantly from modal phonation (0.44%).

CONCLUSION

These results provide preliminary evidence that NR technique can increase CQ with lower levels of jitter compared to straw phonation using a narrow diameter of 2 mm. Future studies should expand enrollment to men, larger age ranges, and patients with hypofunctional symptoms (eg, Parkinson disease) to evaluate the potential benefits of NR as a therapeutic technique.