title: Articulatory Changes in Vowel Production following STN DBS and Levodopa Intake in Parkinson's Disease.
abstract: Purpose. To investigate the impact of deep brain stimulation of the subthalamic nucleus (STN DBS) and levodopa intake on vowel articulation in dysarthric speakers with Parkinson's disease (PD). Methods. Vowel articulation was assessed in seven Quebec French speakers diagnosed with idiopathic PD who underwent STN DBS. Assessments were conducted on- and off-medication, first prior to surgery and then 1 year later. All recordings were made on-stimulation. Vowel articulation was measured using acoustic vowel space and formant centralization ratio. Results. Compared to the period before surgery, vowel articulation was reduced after surgery when patients were off-medication, while it was better on-medication. The impact of levodopa intake on vowel articulation changed with STN DBS: before surgery, levodopa impaired articulation, while it no longer had a negative effect after surgery. Conclusions. These results indicate that while STN DBS could lead to a direct deterioration in articulation, it may indirectly improve it by reducing the levodopa dose required to manage motor symptoms. These findings suggest that, with respect to speech production, STN DBS and levodopa intake cannot be investigated separately because the two are intrinsically linked. Along with motor symptoms, speech production should be considered when optimizing therapeutic management of patients with PD.
authors.affiliation: Centre Interdisciplinaire de Recherche en Réadaptation et en Intégration Sociale, Québec, QC, Canada G1M 2S8.
authors.forename: Vincent
authors.initials: V
authors.lastname: Martel Sauvageau
authors.affiliation: Centre Interdisciplinaire de Recherche sur les Activités Langagières, Université Laval, Québec, QC, Canada G1V 0A6.
authors.forename: Johanna-Pascale
authors.initials: JP
authors.lastname: Roy
authors.affiliation: Département des Sciences Neurologiques, CHU de Québec (Hôpital de l'Enfant-Jésus), Québec, QC, Canada G1J 1Z4.
authors.forename: Léo
authors.initials: L
authors.lastname: Cantin
authors.affiliation: Département des Sciences Neurologiques, CHU de Québec (Hôpital de l'Enfant-Jésus), Québec, QC, Canada G1J 1Z4.
authors.forename: Michel
authors.initials: M
authors.lastname: Prud'Homme
authors.affiliation: Département des Sciences Neurologiques, CHU de Québec (Hôpital de l'Enfant-Jésus), Québec, QC, Canada G1J 1Z4.
authors.forename: Mélanie
authors.initials: M
authors.lastname: Langlois
authors.affiliation: Centre de Recherche, Institut Universitaire en Santé Mentale de Québec, Laboratoire Langage et Cognition, Québec, QC, Canada G1J 2G3.
authors.forename: Joël
authors.initials: J
authors.lastname: Macoir