Effects of spectral content on Horii Oral-Nasal Coupling scores in children

Abstract

A miniature accelerometer and microphone can be used to obtain Horii Oral-Nasal Coupling (HONC) scores to objectively measure nasalization of speech. While this instrumentation compares favorably in terms of size and cost relative to other objective measures of nasality, the metric has not been well characterized in children. Furthermore, the measure is known to be affected by vowel loading, as speech loaded with "high" vowels is consistently scored as more nasal than speech loaded with "low" vowels. Filtering the signals used in computation of the HONC score to better isolate the correlates of nasalization has been shown to reduce vowel-related effects on the metric, but the efficacy of filtering has thus far only been explored in adults. Here, HONC scores for running speech and the vowel portions of consonant-vowel-consonant tokens were calculated for the speech of 26 children, aged 4-9 yrs. Scores were computed using the broadband accelerometer and speech signals, as well as using filtered, low-frequency versions of these signals. HONC scores obtained using both broadband and filtered signals resulted in well-separated scores for nasal and non-nasal speech. HONC scores computed using filtered signals were found to exhibit less withinparticipant variability.

Effects of Biofeedback on Control and Generalization of Nasalization in Typical Speakers

“…HONC data were collected during training with a headset microphone (Shure model WH20; Shure, Inc., Niles, IL) and BU Series 21771 accelerometer (Knowles Electronic, Itasca, IL). The accelerometer signal was band-pass filtered from 400-1000 Hz and the microphone was filtered from 25-420 Hz, allowing for utilization of the low-frequency portion of the signals (Thorp et al, 2013;Varghese et al, 2014). The microphone was placed 7 cm from the mouth at a 45°angle.…”

“…HONC instrumentation is lightweight, doesn't require bulky hardware, and has low power consumption (Stevens et al, 1975). Furthermore, HONC scores are correlated with experts' perception of nasality (Horii, 1983), and can effectively differentiate between nasalized and nonnasalized speech tokens (Mra et al, 1998;Thorp, Virnik, & Stepp, 2013;Varghese, Mendoza, Braden, & Stepp, 2014). In addition, previous work has shown that the use of HONC scores to differentiate between nasalized and nonnasalized speech tokens produces results comparable to the use of nasalance (Thorp et al, 2013).…”

Video Game Rehabilitation of Velopharyngeal Dysfunction: A Case Series

“…This ratio correlates with perceived nasality in healthy adults (Laczi, Sussman, Stathopoulos, & Huber, 2005) and children with VPD (Laczi et al, 2005;Redenbaugh & Reich, 1985). Recent work has led to filtered HONC, in which the accelerometer and microphone signals are bandpass filtered, allowing for comparison of HONC values across participants and vowels (Thorp, Virnik, & Stepp, 2013;Varghese, Mendoza, Braden, & Stepp, 2014).…”