Longitudinal case study of voice quality in spontaneous speech in an adult with severe-profound sensorineural hearing loss: acoustic and auditory-perceptual evaluation of voice.

INTRODUCTION: The auditory system helps control voice production, and the present case study illustrates this relationship and reveals how severe to profound post-lingual Hearing Loss (HL) impacts voice quality and dynamics and how uni- and bi-lateral cochlear implantation (CI) improves performance in spontaneous speech. The purpose of this study was to analyse acoustic and auditory perceptual measures of spontaneous speech produced by an adult with HL before CI, after unilateral CI and after bilateral CI.

METHOD: The study is a longitudinal, retrospective case report and explored voice quality and dynamics in producing spontaneous speech samples through Long-Term Average Spectra (LTAS), Cepstral Peak Prominence (CPP) and fundamental frequency (fo) analysis, auditory-perceptual evaluation by experienced speech and language therapists based on the Vocal Profile Analysis Scheme for Brazilian Portuguese (BP-VPAS).

RESULTS: Outcomes of the LTAS, CPP and BP-VPAS analyses were sensitive to changes in spontaneous speech samples before CI, after unilateral CI and after bilateral CI in an adult Brazilian Portuguese speaker with post lingual HL, contributing to a voice assessment process in a more natural context than a reading task.

CONCLUSIONS: The results showed a positive impact of CI on voice quality and dynamics, and that bilateral CI improved prosodic adjustments in spontaneous speech, highlighting the integration between voice, speech and hearing.