Effect of Noninvasive Brain Stimulation on Hypokinetic Dysarthria in Parkinson's Disease

Effect of Noninvasive Brain Stimulation on Hypokinetic Dysarthria and Brain Plasticity in Parkinson's Disease

Hypokinetic dysarthria (HD) is common in Parkinson's disease (PD) patients and responds only partially to pharmacotherapy and surgery. The investigators will explore long-term effects of repetitive transcranial magnetic stimulation (rTMS) applied over right superior temporal gyrus, brain area known to be engaged in the feedback control of voiced speech. The project results will allow for the identification of potential therapeutic effects of rTMS as a tool that could contribute to the speech therapy of HD in PD patients. The results will also enhance our understanding of brain mechanisms underlying specific long-term effects of rTMS.

A two parallel group, randomized, placebo controlled design will be used. Twenty PD patients will be stimulated in a two weeks long therapeutical sessions (10 sessions). Other twenty PD patients will be stimulated with the same protocol using sham stimulation. An MRI protocol consisting of T1, EPI BOLD, and DTI (diffusion tensor imaging) sequences and speech evaluation (acoustic signal processing and 3F test) will be performed prior to and after 10 days of rTMS and then repeated after 4, 8 and 12 weeks.

Inclusion Criteria:

• patients with clinically established PD (Postuma et al. 2016)

Exclusion Criteria:

• psychiatric disorders, including major depression, hallucinations
• any MRI-incompatible metal in the body
• epilepsy
• lack of cooperation
• presence of dementia