Patrik Šimko, Czech Republic
CEITEC MU Applied neuroscienceAuthor Of 1 Presentation
LONG-TERM EFFECTS OF NON-INVASIVE BRAIN STIMULATION ON HYPOKINETIC DYSARTHRIA IN PARKINSON’S DISEASE
Abstract
Aims
Hypokinetic dysarthria is a common symptom of Parkinson’s disease (PD) which does not respond well to PD treatments. We investigated the long-term effects of multiple-session repetitive transcranial magnetic stimulation on hypokinetic dysarthria in PD.
Methods
A randomized parallel-group sham stimulation-controlled design was used. Patients were randomly assigned to ten sessions of real (1 Hz) or sham stimulation over the right superior temporal gyrus (STG). Stimulation effects were evaluated at weeks 2, 6, and 10 after the baseline assessment. Articulation, prosody, and speech intelligibility were quantified by speech therapist using a validated tool (Phonetics score). Activations of the speech network regions, structural and functional connectivity were measured.
Results
Altogether 33 PD patients completed the study. Linear mixed model showed significant time-by-group interactions for the Phonetics score (p = 0.040). Real as compared to sham stimulation led to increased activations of the left orofacial sensorimotor cortex (OFSM1) (p = 0.032) and left caudate nucleus (p = 0.029) and to increased intrinsic connectivity of the OFSM1 with the stimulated area (p = 0.045). A significant positive correlation was found between the temporal evolution of the Phonetics score and the STG-OFSM1 functional connectivity changes in the real stimulation group (R = 0.449, p = 0.013). DTI analysis revealed that real as compared to sham stimulation significantly increased fractional anisotropy and decreased mean diffusivity in the left anterior arcuate fasciculus (p = 0.002; p = 0.036).
Conclusions
This is the first study to show the long-lasting clinically relevant effects of low-frequency rTMS on hypokinetic dysarthria in PD.