Voice quality and voice dynamics data

Abstract

Acoustic and perceptual auditory analysis procedures present themselves as clinical tools which give support to the understanding of the speech features of hearing impaired children (HIC). Voice quality stems from the overlapped action of the larynx, the supralaryngeal vocal tract and the level of muscular tension throughout the speech flow. Nonetheless, voice dynamics is characterized by frequency, duration and intensity variations. This research aimed at investigating acoustic and perceptive correlates of a HIC child’s voice and dynamic quality. The child, who has a cochlear implanted, had his speech samples collected during speech therapy sessions. The male subject (R), who uses a unilateral cochlear implant (UCI), had his speech production samples recorded when he was 5 (05 samples) and 6 years old (05 samples), and which were later tagged Cut A and Cut B respectively. The recorded corpus was acoustically analyzed through the use of the SGEXpressionEvaluator script (Barbosa, 2009) running on the free software Praat v10. The measures which were automatically extracted by the script correspond to the fundamental frequency –f0, first f0 derivative, intensity, spectral fall and long term spectrum. The perceptual auditory analysis of the voice quality was based on the VPAS-PB script (Camargo e Madureira, 2008). The perceptual auditory judgments and the acoustic measures were subjected to statistical analysis procedures. At first the, the data (perceptual and acoustic) were separately analyzed through a hierarchical and agglomerative cluster analysis. Subsequently, they were examined together through the principal component analysis. Results revealed the existence of correspondence between the acoustic and perceptual auditory data. In the audio recorded data samples from Cut B (one year after the first one) greater variability tendencies in acoustic measures of f0 could be observed associated with laryngeal hyper function at the perceptual level plus silent pauses and the reduction of speech rate. From the integrated acoustic and perceptual analysis it was possible to keep a record of the child’s oral language development process. The data analysis in this study allowed the observation of several interaction levels between the vocal tract (lip movement extension adjusts, tongue and jaw, associated with velopharyngeal adjusts and muscular tension from the larynx), plus the inspection of speech dynamics elements (habitual pitch and speech rate) of a child’s speech who has a UCI implanted during a one-year-speech-therapy-process period. This source of information made the characterization of the child’s evolution possible, especially in terms of perceptual auditory analysis descriptions being phonetically motivated by the speech dynamics quality.