Influence of tDCS on Cortical Plasticity in Patients With Dementia of the Alzheimer Type

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 patients with dementia of the Alzheimer type (DAT) 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 Patients With Dementia of the Alzheimer Type

Conditions
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Dementia of Type Alzheimer

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) Cognitive impairment, which corresponds to a mild to moderate DAT No treatment with AChE inhibitors, or existing stable treatment with AChE inhibitors for over 3 months No motor impairments relevant to everyday life Age 50 to 80 years Existing Insurance certificate Existing informed consent 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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No

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 |
| --- | --- | --- |
| the anodal transcranial direct current stimulation over the primary motor cortex (M1) in patients with dementia of Alzheimer type (DAT) | to investigate whether the anodal transcranial direct current stimulation over the primary motor cortex (M1) in patients with dementia of Alzheimer type (DAT) increases cortical plasticity (measured via motor evoked potentials) compared to a sham stimulation | 1 week | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| tDCS effects on central cholinergic activity in patients with DAT | to investigate whether the anodal transcranial direct current stimulation affect central cholinergic activity (measured via a TMS-protocol) in patients with dementia of Alzheimer type (DAT) compared to a sham stimulation | 1 week | 
| tDCS effects on learning | tDCS-induced changes in learning success (performance in a motor learning paradigm in patients with DAT after tDCS vs. sham stimulation) | 1 week | 
| MR elastography | Comparison of viscoelastic parameters in cerebral MR elastography in patients with DAT | 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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cortical plasticity, transcranial direct current stimulation