Word segmentation based on prosody in Parkinson’s Disease

ABSTRACT

While Parkinson’s Disease (PD) impacts the production of prosody and may lead to dysprosody, its effect on the perception of prosody is less clear. In the current study, we investigated how people with PD (PwPD) segment continuous speech using prosodic cues. We used phonemically identical and prosodically different sequences in French. Twenty-three PwPD and 30 controls took part in the study. PwPD showed similar performance to controls (mean difference in terms of correct responses = 2%, 95% confidence interval = [−4%; 8%]). Using Bayesian statistics, our data is 3.6 times more in favour of the null model compared to the alternative model (i.e. difference between PwPD and controls). It thus seems unlikely that PD impacts the perception of prosody systematically. Furthermore, the cognitive performance of PwPD predicted their performance in our segmentation task. This suggests interesting pathways for future research on the mechanisms underlying the impact of PD on speech processing. Clinically, our findings suggest that adequate evaluation of the cognitive capacity of PwPD would help speech and language therapists in assessing speech processing skills in PwPD and in managing their speech impairments.

KEYWORDS:

• Prosody
• Parkinson’s Disease
• speech perception
• word segmentation

Acknowledgments

We would like to thank all the participants in this study. We are grateful to Clémence Angles-dauriac, Charlotte Crétien, Juliette Galliou, Alice Hardy, Nora Vallejo, and Morgane Villedieu for their valuable help in collecting data. We also thank Laurent Ott for his help with preparing the experiment.

Disclosure statement

The authors have no conflict of interest to report.