Comparative analysis of normal voice characteristics using simultaneous electroglottography and high speed digital imaging

Vocal fold (VF) activity in sustained phonation captured through simultaneous visual observations via direct method (high speed digital imaging: HSDI) and via indirect electroglottographic (EGG) method in normal population were submitted to contrastive analysis. The quantitative parameters used to describe the dynamic properties of the VF vibration included open/closed quotients, and indices that we defined as harmonic ratios. Our analysis also included a Nyquist plot approach that we introduced previously. Results indicate that EGG tracings delivered useful results for the analysis of normal voices and derived a reasonably accurate open quotient value in comparison to the visual analysis. Moreover, recognizable Nyquist plot patterns were obtained for EGG tracings although not identical to that obtained from the HSDI-derived glottal area waveform. Therefore ipso-facto we evaluate the usefulness of EGG compared to visual data in describing specific voice characteristics of normal speakers.

► Comparative analyses of vocal fold (VF) activity in sustained phonation are presented.
► We use high speed digital imaging (HSDI) and electroglottography (EGG) for this study.
► Open quotient and harmonic ratios are used to describe the VF vibratory properties.
► Our analysis also included a Nyquist plot approach that we introduced previously.
► EGG- and HSDI- derived open quotient values are reasonably close for normal voices.