Cathodal tDCS in MCI: A Randomized, Double-Blind, Sham-Controlled Pilot Study

Cathodal Transcranial Direct Current Stimulation (tDCS) in Mild Cognitive Impairment (MCI): A Randomized, Double-Blind, Sham-Controlled Pilot Study

This study evaluates the application of non-invasive brain stimulation in the treatment of Mild Cognitive Impairment (MCI) in adults aged 55-85. Half of the participants will receive transcranial direct current stimulation (tDCS), while the other half will receive sham (like placebo) stimulation.

The purpose of this study is to investigate whether giving transcranial direct current stimulation (tDCS) treatment using an investigational device called the Soterix tES Device (tDCS device) on the right side of the brain can improve performance on cognitive tests. Investigational means that the tDCS device is not approved by the U.S. Food and Drug Administration (FDA) for the use in this study.

tDCS is a non-invasive way to electrically stimulate the brain. The tDCS device is portable and runs on two 9-volt batteries. Electrodes from the tDCS device carry weak electrical current through the scalp and skull and into the brain. When the direction of the electric current flow is called cathodal, the brain under the site of stimulation reduces its activity.

When tasks are performed, certain parts of the brain are activated. Research studies have shown that younger adults and older adults activate similar parts of the brain when performing the same task (a memory task, for example). However, other researchers found older adults who scored worse on memory tasks, and those with Mild Cognitive Impairment, activated an additional part of the brain so both sides of the brain are activated. Researchers are not sure whether this additional activation is helpful or not. Investigators in this study believe that this extra activation may be contributing to worse performance on tasks.

It may be possible to use tDCS to reduce the brain activity on the extra activation (right) side in older adults, to resemble an activation pattern seen in younger adults (or higher scoring cohort). Using cathodal tDCS to reduce brain activity might help the brain in performing tasks.

Inclusion Criteria:

• Male or female outpatients with confirmed MCI diagnosis
• Age 55-85
• Right handed (tested using the Edinburgh handedness inventory)
• Total PHQ-8 of ≤ 16 which signifies no severe depression
• All participants and/or caregivers must be able to provide informed consent

Exclusion Criteria:

• Neurodegenerative disease (e.g. Parkinson's, Huntington's, Multiple Sclerosis) other than MCI
• Previous brain lesion
• Intracranial abnormality such as prior stroke
• History of seizure disorder or epilepsy
• A "true" positive response, after patient clarification, to any question on the modified TMS/tDCS Adult Safety Screen questionnaire that would impact patient safety
• Any history of brain stimulation treatment (e.g., electroconvulsive therapy (ECT), repetitive transcranial magnetic stimulation (rTMS), vagal nerve therapy (VNS), deep brain stimulation (DBS))
• Use of any investigational drug within 4 weeks
• Cardiac pacemakers, implanted medication pumps, intracardiac lines; acute or unstable cardiac disease; intracranial implants (e.g., aneurysm clips, shunts, stimulators, cochlear implants, or electrodes) or any other metal object within or near the head (exception: mouth/dental work) that cannot be safely removed
• Known or suspected pregnancy (extremely unlikely as the age range for this study is 55-85 years)