Influence of tDCS on Cortical Plasticity in Healthy Older Adults

Study Overview
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Brief Summary
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The aim of this study is to investigate whether the anodal transcranial direct current stimulation (tDCS) over the primary motor cortex (M1) in healthy older adults leads to an increase in cortical plasticity (change in motor evoked potentials (MEP) in mV).

Official Title
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Influence of Transcranial Direct-current Stimulation on Cortical Plasticity in Healthy Older Adults

Conditions
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Healthy Older Adults

Intervention / Treatment
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* Device: transcranial direct current stimulation
* Device: sham stimulation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: right-handed according to the Oldfield Händigkeits inventory (lateralization index >70)(1971) no obvious cognitive impairment (MMSE>26, Demtect>13) age between 50 and 80 years Exclusion Criteria: Severe neurological / psychiatric or pre-existing internist conditions because additional cognitive deficits are expected Epilepsy, epileptic seizure in medical history Cognitive deficit (MMSE <20) Depressive episode (Beck Depression Inventory (BDI) > 12) intake of centrally active drugs <3 months , particularly acetylcholinesterase inhibitors Pregnancy Pacemaker (contraindication for MRI) Other metal parts in the body (contraindication for MRI)

Ages Eligible for Study
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Minimum Age: 50 Years
Maximum Age: 80 Years

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: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: transcranial direct current stimulation<br> | Device: transcranial direct current stimulation<br> <br> |
| Placebo Comparator: sham stimulation<br> | Device: sham stimulation<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| anodal transcranial direct current stimulation (tDCS) over the primary motor cortex (M1) in healthy older adults | to investigate whether the anodal transcranial direct current stimulation over the primary motor cortex (M1) in healthy older adults increases cortical plasticity (measured via motor evoked potentials)compared to sham stimulation | 1 week | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Comparison of tDCS-induced changes on central cholinergic activity | to investigate weather anodal transcranial direct-current stimulation affect central cholinergic activity (measured via a TMS-protocol) in healthy older adults compared to sham stimulation | 1 week | 
| Comparison of tDCS-induced changes in the learning success | tDCS-induced changes on learning success (performance in a motor learning paradigm in healthy older adults after tDCS vs. sham) | 1 week | 
| MR elastography | Comparison of viscoelastic parameters in cerebral MR elastography in healthy older adults | 1 week | 
| genetic polymorphism, ApoE4 | optional assessment of genetic Apo4 epsilon status for assessment of differences in cortical plasticity and elasticity between Apo4 epsilon positive and negative participants | once | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Transcranial Direct Current Stimulation, Healthy older adults Cortical Plasticity