Effects of Transcranial Direct Current Stimulation on Fine Motor Skills in Parkinson's Disease: a Pilot Study

Study Overview
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Brief Summary
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The purpose of this pilot study is to determine the effect of transcranial direct current stimulation (tDCS) on brain activity and fine motor skills in patients with Parkinson's disease compared to healthy controls.

Detailed Description
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The pilot study will involve a double-blind, sham controlled cross-over design where participants will receive anodal and sham tDCS stimulation in a randomized order. Differences in brain activity and fine motor skill performance between groups and after tDCS stimulation will be compared.

Conditions
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Parkinson's Disease, Transcranial Direct Current Stimulation, Fine Motor Skills, Handwriting

Intervention / Treatment
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* Device: transcranial direct current stimulation (tDCS)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosed with idiopathic PD, according to the UK Brain Bank criteria Hoehn and Yahr (H&Y) stage II in the 'on'-phase of the medication cycle Right dominant PD Exclusion Criteria: Cognitive impairment (MMSE < 23) Visuo-spatial deficits (measured by the Rey-Osterrieth Complex Figure (ROCF) test) Left-handedness (evaluated by the Edinburgh Handedness scale) Depression Pregnancy Alcohol abuse Aneurysm clips Pacemaker Neurostimulator Implemented defibrillator Magnetically activated implant or device Implemented pump Spinal cord simulator Implemented hearing aid Artificial or prosthetic limb Metal parts in the body Any external or internal metal Artificial heart valve Other implants History of brain surgery Migraine Family history of Epilepsy Other contra-indications for tDCS and Transcranial Magnetic Stimulation (TMS) Other neurological, psychiatric or interfering upper limb problems
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Anodal tDCS<br>20 minutes, 1.0 mA unilateral-anodal motor cortex (M1) tDCS stimulation | Device: transcranial direct current stimulation (tDCS)<br> <br> |
| Sham Comparator: Sham tDCS<br>20 minutes, sham tDCS stimulation | Device: transcranial direct current stimulation (tDCS)<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in writing amplitude | Centimeter (cm) | post-stimulation (immediately after) and retention (1 week) | 
| Change in writing velocity | Centimeter per second (cm/s) | post-stimulation (immediately after) and retention (1 week) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in speed on the Purdue Pegboard task | Number of pegs placed in 30 seconds | post-stimulation (immediately after) and retention (1 week) | 
| Change in cortical excitability | Motor Evoked Potentials (MEP) peak to peak amplitude and latency - Measured with single-pulse Transcranial Magnetic | post-stimulation (immediately after) and retention (1 week) | 
| Change in Short-Latency Intracortical Inhibition (SICI) | Measured with double-pulse Transcranial Magnetic Stimulation (TMS) | post-stimulation (immediately after) and retention (1 week) | 
| Change in cortical silent period (cSP) | Measured with single-pulse Transcranial Magnetic | post-stimulation (immediately after) and retention (1 week) |