What if someone with Alzheimer’s could cure themselves, simply by looking at flashing lights and listening to clicking sounds?
A new study led by M.I.T researchers found that when mice with symptoms of Alzheimer’s — a neurodegenerative disease — were exposed to flickering lights and clicks, their memory and other cognitive impairments improved. Not only that, the treatment swept away large amounts of amyloid plaques — harmful proteins associated with Alzheimer’s.
It’s too early to say whether light and sound will work in humans, said study lead author Li-Huei Tsai, director of MIT’s Picower Institute for Learning and Memory, in a statement. But the findings offer the exciting possibility of a non-invasive, drug-free treatment for Alzheimer’s.
Gamma brainwaves and Alzheimer’s
The study used light and sound delivered at 40 hertz — or 40 flashes or clicks per second — for one hour a day, for seven days. This frequency stimulated gamma oscillations, brainwaves which are reduced in people with Alzheimer’s, and cleared away disease-related plaque in the hippocampus, the area of the brain that handles memory.
Other studies have shown that stimulating gamma brainwaves may benefit Alzheimer’s patients.
The treatment also reduced another Alzheimer’s-related protein called tau, tangles that develop in cells. And it spurred activity of microglia, immune cells which help sweep away debris in the brain.
Light and sound work better together
In a 2016 study, Tsai used only light, but the effects were limited to a part of the brain associated with vision. This latest study shows that a combined treatment may be more effective than using light or sound on their own.
“What we have demonstrated here is that we can use a totally different sensory modality to induce gamma oscillations in the brain,” says Tsai.
When the mice had a week’s break between treatments, the effects had faded, suggesting treatment would need to be continual for the benefits to stick.
As part of the new study, researchers also tested the effect of 40-hertz clicks on the mice’s cognitive abilities. After one week, the mice were faster at finding their way through a maze, and were better able to recognize an object they’d never seen before. The sound treatment also strengthened blood vessels, which further helped clear away plaque.
The researchers are starting to enroll patients with early-stage Alzheimer’s to test the treatment on humans. If you have a loved one with Alzheimer’s, you can sign him or her up for a clinical trial here.