EGG wave shape differences in children and adults (Patel & Ternström, 2021)

Purpose: The purpose of this study is to identify the extent to which various measurements of contacting parameters differ between children and adults during habitual range and overlap vocal frequency/intensity, using voice map–based assessment of noninvasive electroglottography (EGG).

Method: EGG voice maps were analyzed from 26 adults (22–45 years) and 22 children (4–8 years) during connected speech and vowel /a/ over the habitual range and the overlap vocal frequency/intensity from the voice range profile task on the vowel /a/. Mean and standard deviations of contact quotient by integration, normalized contacting speed, quotient of speed by integration, and cycle-rate sample entropy were obtained. Group differences were evaluated using the linear mixed model analysis for the habitual range connected speech and the vowel, whereas analysis of covariance was conducted for the overlap vocal frequency/intensity from the voice range profile task. Presence of a “knee” on the EGG wave shape was determined by visual inspection of the presence of convexity along the decontacting slope of the EGG pulse and the presence of the second derivative zero-crossing.

Results: The contact quotient by integration, normalized contacting speed, quotient of speed by integration, and cycle-rate sample entropy were significantly different in children compared to (a) adult males for habitual range and (b) adult males and adult females for the overlap vocal frequency/intensity. None of the children had a “knee” on the decontacting slope of the EGG slope.

Conclusion: EGG parameters of contact quotient by integration, normalized contacting speed, quotient of speed by integration, cycle-rate sample entropy, and absence of a “knee” on the decontacting slope characterize the wave shape differences between children and adults, whereas the normalized contacting speed, quotient of speed by integration, cycle-rate sample entropy, and presence of a “knee” on the downward pulse slope characterize the wave shape differences between adult males and adult females.

Supplemental Material S1. Voice maps and electroglottographic wave shapes for all participants from the speech range profile task in the

habitual range.

Supplemental Material S2. Voice maps and electoglottographic wave shapes for all participants from the voice range profile task on vowel /a/.

Supplemental Material S3. Union maps of electroglottographic parameters for all participants per group, from the voice range profile task.

Patel, R. R., & Ternström, S. (2021). Quantitative and qualitative electroglottographic wave shape differences in children and adults using voice map–based analysis. Journal of Speech, Language, and Hearing Research. Advance online publication. https://doi.org/10.1044/2021_JSLHR-20-00717