Henry, Trent M.

Laryngeal high-speed videoendoscopy (HSV) is a powerful tool to study the detailed vibratory characteristics of the vocal folds. The use of HSV in connected speech enables us to study the transitory behaviors of the vocal folds during different vocalizations. The onset and offset of voicing contain critical information about the health and function of the vocal folds. In this work, HSV is used to study how the voicing begins/ends at the laryngeal level at the onset/offset of phonation. HSV data were obtained during production of connected speech from participants with non-pathological voices and patients with different neurogenic voice disorders. The data collection was performed using a Photron FASTCAM mini AX200 high-speed camera coupled with a flexible nasolaryngoscope. The glottal attack time and glottal offset time were measured at the onset and offset of different vocalizations, respectively, from the HSV data. The findings show differences in the onset and offset measures between the two groups of participants. The vocal fold vibratory behaviors will be discussed qualitatively and quantitatively using these measures. The use of HSV in connected speech could help us develop accurate voice assessment procedures to assess the vocal folds function during connected speech.

Adductor spasmodic dysphonia (AdSD) is a neurological voice disorder, which affects the control of intrinsic muscles of the larynx during speech. Our previous research has shown that high-speed videoendoscopy (HSV) can be used to measure the glottal attack time for patients with AdSD during connected speech. This study builds upon that to analyze the acoustic signal during the phonation onset and prephonatory adjustments. The phonation onset events are quantified using the HSV data that were obtained simultaneously with the acoustic data. We analyze the power and energy waveform of the acoustic signal during vocal folds’ first contact, first oscillation, and transitory behaviors, extracted from high-temporal resolution HSV data. The data were obtained from five patients with AdSD and five vocally normal participants. The data were recorded while the participant produced: 2 productions of vowel /i/ at habitual pitch and loudness, 2 with a soft glottal attack and 2 with a hard glottal attack, six CAPE-V sentences, and the “Rainbow Passage.” The HSV system included a monochrome high-speed camera coupled with a flexible nasolaryngoscope. The results of this study could assist for more accurate clinical management of adductor spasmodic dysphonia.