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Objective: This study aimed to evaluate lenition, a phonological process involving consonant weakening, as a diagnostic marker for differentiating Parkinson’s Disease (PD) from Atypical Parkinsonism (APD). Early diagnosis is critical for optimizing treatment outcomes, and lenition patterns in stop consonants may provide valuable insights into the distinct motor speech impairments associated with these conditions. Methods: Using Phonet, a machine learning model trained to detect phonological features, we analyzed the posterior probabilities of continuant and sonorant features from the speech of 142 participants (108 PD, 34 APD). Lenition was quantified based on deviations from expected values, and linear mixed-effects models were applied to compare phonological patterns between the two groups. Results: PD patients exhibited more stable articulatory patterns, particularly in preserving the contrast between voiced and voiceless stops. In contrast, APD patients showed greater lenition, particularly in voiceless stops, coupled with increased articulatory variability, reflecting a more generalized motor deficit. Conclusions: Lenition patterns, especially in voiceless stops, may serve as non-invasive markers for distinguishing PD from APD. These findings suggest potential applications in early diagnosis and tracking disease progression. Future research should expand the analysis to include a broader range of phonological features and contexts to improve diagnostic accuracy.
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Neural network-based measure of consonant lenition in Parkinson's Disease
This study investigated the effects of Parkinson’s disease (PD) and various linguistic factors on the degree of lenition in Spanish stops. Lenition was estimated from posterior probabilities calculated by recurrent neural networks trained to recognize sonorant and continuant phonological features. Firstly, individuals with PD exhibited a higher degree of lenition in their voiceless stops compared to healthy controls, suggesting that PD significantly impacts the articulatory control of stops, resulting in more pronounced lenition. Secondly, lenition was significantly more advanced for dental stops than bilabial stops, further suggesting that the muscles controlling tongue tip movement are more affected than those involved in lip movement among PD patients. These findings are consistent with previous literature. Importantly, the results highlight the sensitivity of Phonet in quantifying lenition in this group of PD patients.
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- Award ID(s):
- 2037266
- PAR ID:
- 10639682
- Publisher / Repository:
- Acoustical Society of America
- Date Published:
- Page Range / eLocation ID:
- 060003
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1121/2.0001913
