Subglottal resonances of American English speaking children

Abstract

This paper presents an investigation of children's subglottal resonances (SGRs), the natural frequencies of the tracheo-bronchial acoustic system. A total of 43 children (31 male, 12 female) aged between 6 and 18 yr were recorded. Both microphone signals of various consonant-vowel-consonant words and subglottal accelerometer signals of the sustained vowel /ɑ/ were recorded for each of the children, along with age and standing height. The first three SGRs of each child were measured from the sustained vowel subglottal accelerometer signals. A model relating SGRs to standing height was developed based on the quarter-wavelength resonator model, previously developed for adult SGRs and heights. Based on difficulties in predicting the higher SGR values for the younger children, the model of the third SGR was refined to account for frequency-dependent acoustic lengths of the tracheo-bronchial system. This updated model more accurately estimates both adult and child SGRs based on their heights. These results indicate the importance of considering frequency-dependent acoustic lengths of the subglottal system.

Vocal tract shape and acoustic adjustments of children during phonation into narrow flow-resistant tubes

“…The frequency of F Sg1 increased to 755 Hz during flow-resistant tube phonation, as expected based on Lulich and Arsikere (2015). Although this was a statistically significant increase, it represents an increase of less than one standard deviation, and is still very similar to the mean values reported for 6-to 9-year-old children by Lulich et al (2011b) and for 6-to 18-year-old children in the study by Yeung et al (2018). Furthermore, we could not rule out the possibility that the change observed in F Sg1 was due to other causes, such as larynx lowering, instead of, or in addition to, wall stiffening.…”

“…Among children in the age range 6-to 9-years-old, the mean frequency of F Sg1 was 780 Hz in 3 boys, 2 girls (Lulich et al, 2011b) and 744 Hz in 12 boys and 3 girls (Yeung et al, 2018). The mean first subglottal frequency of 694 Hz found in the present study in the no-flow resistant tube condition is somewhat lower compared to previous findings in children (Lulich et al, 2011b;Yeung et al, 2018), but each are within one standard deviation of our mean value. The frequency of F Sg1 increased to 755 Hz during flow-resistant tube phonation, as expected based on Lulich and Arsikere (2015).…”

“…Subglottal resonances have been investigated in both adults (Chi and Sonderegger, 2007;Cranen and Boves, 1987;Csapo et al, 2009;Dogil et al, 2010;Hanna et al, 2018;Ishizaka et al, 1976;Lulich, 2010;Lulich et al, 2012;van den Berg, 1960) and in children (Lulich, 2010;Lulich et al, 2011b;Yeung et al, 2018). Among children in the age range 6-to 9-years-old, the mean frequency of F Sg1 was 780 Hz in 3 boys, 2 girls (Lulich et al, 2011b) and 744 Hz in 12 boys and 3 girls (Yeung et al, 2018). The mean first subglottal frequency of 694 Hz found in the present study in the no-flow resistant tube condition is somewhat lower compared to previous findings in children (Lulich et al, 2011b;Yeung et al, 2018), but each are within one standard deviation of our mean value.…”

A Frequency Normalization Technique for Kindergarten Speech Recognition Inspired by the Role of fo in Vowel Perception

“…To verify the relationship between formants and fo for child vowel productions, we measured fo, F 1, F 2, and F 3 from the vowels of 4 hVd words in the WashU-UCLA Child Subglottal Resonances Database [35], which includes 43 children between the ages of 6 and 18 years. Two tense vowels, /i/ and /A/, and two lax vowels, /I/ and /2/, were chosen for analysis.…”