Speech abnormalities in Parkinson's disease (PD) are heterogeneous and often considered resistant to levodopa. However, human hearing may miss subtle treatment-related speech changes. Digital speech biomarkers offer a sensitive alternative to measure such changes objectively. Speech was recorded in 51 PD patients during ON and OFF medication states and compared to 43 healthy controls matched for language and gender. Acute levodopa effects were significant in prosodic (F0 standard deviation, p = 0.03, effect size = 0.47), respiratory (intensity slope, p = 0.02, effect size = 0.49), and spectral domains (LTAS mean, p = 0.01, effect size = 0.35). Stepwise backward regression identified 8 biomarkers reflecting hypokinetic symptoms, 6 for dyskinetic symptoms, and 7 for medication-state transitions. Hypokinetic compound score correlated strongly with MDS-UPDRS-III changes (r = 0.70; MAE = 6.06/92), and the dyskinetic compound score with dyskinesia ratings (r = 0.50; MAE = 1.81/12). Medication-state transitions were detected with AUC = 0.86. This study highlights the potential of digital speech biomarkers to objectively measure levodopa-induced changes in PD symptoms and medication states.

• Publication type
• Journal Article MeSH

Pallidal deep-brain stimulation of the internal globus pallidus (GPi-DBS) is an effective treatment for dystonia. However, GPi-DBS may cause important stimulation-induced side effects such as hypokinetic dysarthria, which is particularly manifested by articulation rate abnormalities. However, little data regarding the effect of the location of the electrode and stimulation parameters for pallidal stimulation on articulation rate in dystonia is available. Speech data were acquired from 18 dystonic patients with GPi-DBS and 18 matched healthy controls. Each of dystonic patients was tested twice within 1 day in both the GPi-DBS ON and GPi-DBS OFF stimulation conditions. Compared to healthy controls, the decreased diadochokinetic rate and slower articulation rate in dystonic patients were observed in both stimulation conditions. No significant differences in speech rate measures between stimulation conditions were detected with no relation to contact localization and stimulation intensity. Our findings do not support the use articulation rate as a surrogate marker of stimulation-induced changes to the speech apparatus in dystonia.

• Keywords
• Acoustic analysis, Deep-brain stimulation, Dysarthria, Dystonia, Pallidal, Speech,
• MeSH
• Adult MeSH
• Dysarthria etiology   MeSH
• Dystonic Disorders therapy   MeSH
• Globus Pallidus * MeSH
• Deep Brain Stimulation adverse effects   MeSH
• Middle Aged MeSH
• Humans MeSH
• Adolescent MeSH
• Young Adult MeSH
• Aged MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Adolescent MeSH
• Young Adult MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH