Can Transcranial Magnetic Stimulation Treat Alzheimer's Disease?

Transcranial Magnetic Stimulation (TMS) is a relatively new way to use magnetism to affect the brain. It is non-invasive, meaning that the procedure does not require any type of surgery; rather, it is conducted by transmitting magnetic pulses through the brain by pressing a machine against the head. Is it possible that this science-fiction-like procedure can help people with Alzheimer's disease?

Most commonly, TMS has been studied as a way to treat depression that won’t respond to antidepressant medications or counseling therapy. Several studies have been conducted and have shown TMS to be quite effective in reducing the level of depression for people who have not responded to medications.

TMS is currently being researched in a variety of fields, including Alzheimer’s, Parkinson’s, stroke, depression, obsessive-compulsive disorder and more, with varying degrees of effectiveness.

What Is Repetitive TMS?

Repetitive TMS (rTMS) is when a series of TMS is performed over time.

TMS and Alzheimer’s Disease

TMS, specifically repetitive TMS (rTMS), has been researched as an intervention for people with Alzheimer’s disease. Several research studies have studied the effect of TMS on people whose cognitive functioning is impaired, whether through vascular dementia, Alzheimer’s, mild cognitive impairment or other types of dementia. Often, the application of rTMS is combined with cognitive training over a period of a few weeks, with testing done prior to the TMS and cognitive training, partway through, at the end of and several months following the TMS and cognitive training.

Research Studies

Researchers conducted a small study involving eight participants who received both rTMS and cognitive training daily for six weeks and then twice a week for the next three months. The participants' cognitive functioning was assessed prior to the start of the study, six weeks into the study and four and a half months after the start of the study. The scores on the Alzheimer's Disease Assessment Scale-Cognitive were improved by approximately 4 points both at six weeks into the study and at the four and a half month mark.

Several other studies involving the application of rTMS alone without cognitive training have been conducted with fairly positive results as well. After receiving rTMS, participants in various studies demonstrated improvements in auditory sentence comprehension, action naming, and object naming ability.

Some research found that those with early-stage dementia showed more improvement in cognition than those with middle-stage or late-stage dementia.

Thus far, no significant side effects have been identified, and the benefits have been demonstrated in people with mild (early stage), moderate (middle-stage) and severe Alzheimer's disease.

TMS as a Diagnostic Tool?

Some research has found that TMS may be an accurate, non-invasive way to diagnose Alzheimer's disease and differentiate it from frontotemporal dementia and normal, healthy research participants.

Further Clinical Trials Are Needed

It's important to note that more study is needed, as these studies with rTMS typically have involved smaller numbers of participants and were structured for shorter periods of time. There are multiple clinical trials underway currently to continue the research involving rTMS. You can view those clinical trials at clinicaltrials.gov and search under "transcranial magnetic stimulation Alzheimer's" or visit TrialMatch, a service available through the Alzheimer's Association.

A Word From Verywell

Medications to treat Alzheimer's and other types of dementia have been quite limited in their effectiveness. They also come with side effects, some of which are fairly significant. Repetitive transcranial magnetic stimulation has the potential to improve cognition and increase daily functioning without the risk of serious side effects.