Investigating if a Stronger tDCS Intensity is More Effective for Improving Naming Ability in People Living With Alzheimer's Disease

Study Overview
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Brief Summary
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There is currently little symptomatic therapy for Alzheimer's Disease (AD) and nothing effective for individuals with Frontotemporal dementia (FTD). However, neuromodulation with transcranial direct current stimulation (tDCS) has the potential to be a clinically effective therapy for both AD and FTD. The challenge now is to specify the parameters and conditions under which tDCS is most effective to transition from the laboratory to clinical medicine. tDCS studies typically report significant group effects despite the variability demonstrated among participants, with some showing clear, meaningful improvement, while others only show statistical improvement or none at all. These variable results may be related to the conventional stimulation intensity level of 2mA. The investigators predict that administering tDCS at 4.0 mA, a more significant number of participants would show a meaningful response, and those who improve at 2mA may improve even more from 4.0mA due to having a larger electric field produced. The investigators aim to test this hypothesis in people with Alzheimer's Disease.

Official Title
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Investigating if a Stronger tDCS Intensity is More Effective for Improving Naming Ability in People Living With Alzheimer's Disease

Conditions
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Alzheimer Disease

Intervention / Treatment
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* Device: transcranial direct current stimulation and naming training


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Mild to Moderate AD Score between 18 and 25 on the MoCA Score on the Cambridge Naming Task during the pre-assessment Exclusion Criteria: No history of stroke or TBI No shunts or metal in the body No history of significant heart disease, alcoholism and drug use

Ages Eligible for Study
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Minimum Age: 50 Years
Maximum Age: 90 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: Crossover Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 4mA Stimulation<br> | Device: transcranial direct current stimulation and naming training<br>* Participants will receive mild stimulation or no stimulation along with naming training<br>|
| Active Comparator: 2mA Stimulation<br> | Device: transcranial direct current stimulation and naming training<br>* Participants will receive mild stimulation or no stimulation along with naming training<br>|
| Sham Comparator: SHAM<br> | Device: transcranial direct current stimulation and naming training<br>* Participants will receive mild stimulation or no stimulation along with naming training<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Naming Training | The primary outcome measure will be change on the naming lists administered, both a trained version and an untrained version. This change will be measured in terms of the number of images correctly named post-training compared to baseline | 3 months |