Acoustic analysis of voice in school teachers

Abstract

Introduction: The term ‘voice’ is the acoustic energy generated from the vocal tract that are characterized by their dependence on vocal fold vibratory pattern. Teachers as professional voice users are afflicted with dysphonia and are discouraged with their jobs and seek alternative employment. Loud speaking and voice straining may lead to vocal fatigue and vocal fold tissue damage. The objective of the study is to assess the quality of voice of school teachers before and after teaching practice. Methods: Sixty teachers from various schools, volunteered to participate in this study. Acoustic analysis Doctor Speech Tiger Electronics, USA was used to assess the voice quality of the school teachers before and after teaching practice. The data were collected and analyzed using Doctor Speech Tiger Electronics, USA. Analysis was performed in terms of perturbation (jitter and shimmer), fundamental frequency, harmonic to noise ratio and maximum phonation time. Results: We found statistically significant difference in all the four parameters except the Jitter value. The fundamental frequency and shimmer value has significantly increased (P<0.001) and (P=0.002) respectively after teaching practice. Unlikely, there was significant decrease in harmonic to noise ratio value (P<0.001) and maximum phonation time value (P<0.01) after teaching practice. Conclusions: Vocal abuse, overuse, or misuse in teaching practice over a long period of time can result in inadequate phonatory pattern due to vocal fold tissue damage, which ultimately results in vocal nodules or polyps. So voice evaluation is particularly important for professional voice users and for the people who are concerned about their quality of voice.