The Effects of Intensive Speech Treatment on Intelligibility in Spanish Speakers with Parkinson's Disease

The motivation of this study was to examine the effects of intensive speech treatment on the conversational intelligibility of Spanish speakers with Parkinson’s Disease (PD). It also aimed at investigating several acoustic variables in the speech of this population. Sixteen speakers with a medical diagnosis of PD participated in this study and their voice recordings were analyzed pre- and post-treatment. The intelligibility measures of transcription accuracy and median ease-of-understanding ratings increased significantly immediately post-treatment and gains were maintained at the one-month follow-up. The acoustic variables of vowel space and voice onset time did not change significantly pre-to-post treatment, whilst the prosodic targets of intensity and mean fundamental frequency increased significantly as a result of treatment. These findings support the implementation of intensive voice intervention to improve intelligibility in Spanish dysarthria. Clinical and theoretical considerations are discussed