Effects of the Lung Volume on the Electroglottographic Waveform in Trained Female Singers

Abstract

Objectives. To determine if in singing there is an effect of lung volume on the electroglottographic waveform, and if so, how it varies over the voice range. Study design. Eight trained female singers sang the tune "Fr ere Jacques" in 18 conditions: three phonetic contexts, three dynamic levels, and high or low lung volume. Conditions were randomized and replicated. Methods. The audio and EGG signals were recorded in synchrony with signals tracking respiration and vertical larynx position. The first 10 Fourier descriptors of every EGG cycle were computed. These spectral data were clustered statistically, and the clusters were mapped by color into a voice range profile display, thus visualizing the EGG waveform changes under the influence of f o and SPL. The rank correlations and effect sizes of the relationships between relative lung volume and several adduction-related EGG wave shape metrics were similarly rendered on a color scale, in voice range profile-style ʻvoice maps.ʼ Results. In most subjects, EGG waveforms varied considerably over the voice range. Within subjects, reproducibility was high, not only across the replications, but also across the phonetic contexts. The EGG waveforms were quite individual, as was the nature of the EGG shape variation across the range. EGG metrics were significantly correlated to changes in lung volume, in parts of the range of the song, and in most subjects. However, the effect sizes of the relative lung volume were generally much smaller than the effects of f o and SPL, and the relationships always varied, even changing polarity from one part of the range to another. Conclusions. Most subjects exhibited small, reproducible effects of the relative lung volume on the EGG waveform. Some hypothesized influences of tracheal pull were seen, mostly at the lowest SPLs. The effects were however highly variable, both across the moderately wide f o -SPL range and across subjects. Different singers may be applying different techniques and compensatory behaviors with changing lung volume. The outcomes emphasize the importance of making observations over a substantial part of the voice range, and not only of phonations sustained at a few fundamental frequencies and sound levels.

Morphometric Correlations of the Voice Category (VC) in Professional Singers with Oropharyngeal and Laryngeal Anatomy Using Stroboscopy and Cervical Posteroanterior Radiography

“…Singing is considered a type of human expression [9] [10] [11] and a complicated procedure that can be influenced by physical, psychological, environmental social and cultural factors [9] [12] [13] [14] [15]. Several researchers have attempted to quantify the factors that influence and constitute this phenomenon, as well as the morphometric and physiological characteristics of the larynx, while singing takes place [16]- [22].…”

Stroboscopic Evaluation of the Vocal Folds’ Morphometric Characteristics, between the Different Voice Categories on Professional Singers

“…Furthermore, other studies have suggested that there is a relationship between laryngeal size (length, shape and thickness of the vocal folds) and qualitative vocal characteristics (pitch, loudness and timbre), as they are observed clinically by vocal coaches and ENT doctors. The morphological characteristics of the vocal folds seem to differ between voice categories, and affect the voice production while singing [18] [19] [20] [21]. Our purpose was to evaluate the vocal folds' characteristics, using the examination method of stroboscopy.…”

Quantitative and Qualitative Electroglottographic Wave Shape Differences in Children and Adults Using Voice Map–Based Analysis

“…In any nonempty cell, one to several hundred phonatory cycles may be represented. It has been shown that voices on repeated visits to the same f o and SPL tend to be quite consistent (Ternström et al, 2020). Provided that the voice production settings remain generally constant during the recording, a parameter mean in a cell only becomes more stable (i.e., smaller confidence interval and standard error) as more phonatory cycles are accumulated.…”

“…Voice maps are thus easy to interpret qualitatively on visual inspection, and they render a wealth of numeric data in a compact form across the voice range. Furthermore, mapped data can be compared quantitatively across groups and/or conditions (Lã & Ternström, 2020;Ternström et al, 2020). Voice-mapping technology also affords real-time visual feedback, which is helpful for eliciting the desired productions from the participants (Hallin et al, 2012;Holmberg et al, 2007) across the targeted voice range.…”

“…Combining the real-time technology of voice maps with EGG analysis allows the automated collection and analysis of very many EGG cycles across the f o and SPL range. Studies utilizing the voice map technique for EGG analysis have been conducted on vocally healthy adults who are either trained classical singers (Lã & Ternström, 2020;Ternström et al, 2020) or have 1-5 years of singing experience in amateur choirs (Selamtzis & Ternström, 2014 using the VRP vowel task. This study is an initial attempt to further our knowledge of the EGG wave shapes in children with the use of voice maps of not only the VRP task but also of connected speech using the SRP task.…”