Acoustic Analysis of Intonation in Persons with Parkinson's Disease Receiving Transcranial Magnetic Stimulation and Intensive Voice Therapy

• Main Author: Li, Qiang
• Language: EN
• Published: University of Louisiana at Lafayette 2019
• Subjects: Linguistics|Speech therapy
• Online Access: http://pqdtopen.proquest.com/#viewpdf?dispub=10843550

<p> Intonation is one of the prosodic features manifested acoustically in the fundamental frequency (F0). Intonation abnormality is common and prominent in the speech of persons with Parkinson's disease (PD). Intensive speech therapies such as Lee Silverman Voice Treatment (LSVT-LOUD^&reg;) have been demonstrated effective for increasing vocal intensity and F0 variability, but no prior studies have examined linguistic features of intonation before and after treatment in PD. Additionally, transcranial magnetic stimulation (TMS) has been demonstrated as an appropriate adjuvant to a primary treatment. It is reasonable to hypothesize that intonation abnormality will be improved after the combined modality treatment of LSVT-LOUD^&reg; and TMS. To examine this hypothesis, the current research investigated acoustically five intonational features including F0 declination, resetting, emphasis, terminal fall, and syntactic pre-junctural fall in twenty PD participants, receiving LSVT-LOUD^&reg; alone, or combined with TMS delivered to the left or right cerebral hemisphere. The primary experiment was designed and carried out by Shalini Narayana and colleagues in their project funded by the Michael J. Fox Foundation for Parkinson's Research. They collected and provided the recorded reading samples for the current study. </p><p> F0 changes of each of five intonational feature were measured before and after the combined modality treatment, and at two months follow-up, then analyzed statistically. The results revealed that F0 declination, emphasis, and terminal fall changed significantly from pre- to post-treatment, and the changes of declination and terminal fall were maintained at the follow-up evaluations. </p><p> The observed changes in intonation were attributed to LSVT alone, which caused large changes of F0 magnitude. F0 resetting and syntactic pre-junctural fall did not change significantly following treatment, probably because these intonational features need very precise fine motor control of the intrinsic laryngeal muscles to make small-range, rapid F0 adjustments, which were not improved by LSVT in present PD participants. Difficulties with syntactic processing previously reported in PD may have contributed to the lack of improvement in resetting and pre-junctural fall, since these F0 features are used to mark syntactic boundaries within utterances. Consideration of incorporation of linguistic intonation to speech intervention for speakers with PD is suggested for future clinical research.</p><p>