The aim of this study was to analyze the effects of a speech-language intervention on speech expressiveness based on perceptual data of voice quality and vocal dynamics in teachers from a public state school in Paraíba, Brazil. The study was based on the Phonetic Model of Voice Quality Description and used the Vocal Profile Analysis for Brazilian Portuguese (VPA-PB) protocol. This protocol allows a detailed analysis of vocal tract, laryngeal, and muscular tension settings, as well as prosodic elements, in order to describe the voice quality and vocal dynamics that characterize the speaker. This interventional study with a qualitative-quantitative approach was approved by the Human Research Ethics Committee of the Federal University of Paraíba (CAAE 65750222.1.0000.5188). Four teachers from a state military school in the city of João Pessoa participated in the study. Four weekly theoretical-practical workshops were conducted, addressing breathing, articulation, modulation of pitch and intensity, resonance, and vocal warm-up. Speech samples (VPA-PB sentences and classroom context) were collected before and after the intervention and analyzed by three expert judges. Preliminary results showed a reduction in laryngeal and vocal tract hyperfunction, a decrease in harsh voice, increased variability of pitch and loudness, as well as improved respiratory support, suggesting improvements in voice quality and speech expressiveness. These findings suggest that the proposed intervention was effective in promoting more balanced vocal settings and greater expressive flexibility, resulting in more natural and efficient speech production with reduced phonatory effort.
Penha et al. (Thu,) studied this question.