Alzheimer’s disease is a brain disorder that affects millions globally, and there’s currently no cure. This has driven the search for new treatments. Recent research suggests that sensory stimulation could offer a noninvasive and promising therapy for the condition.
Over the past decade, research led by The Picower Institute for Learning and Memory at MIT has explored how 40Hz “gamma” frequency sensory stimulation could help treat Alzheimer’s disease.
Initially tested on mice, the approach has since gained global interest, with growing evidence suggesting it may enhance brain health in both animals and humans. A new review describes the progress and outlines key scientific and clinical questions surrounding this noninvasive therapy.
Li-Huei Tsai, Picower professor of neuroscience at MIT, director of MIT’s Aging Brain Initiative, and senior author of the new review with postdoc Jung Park, said, “As we’ve made all our observations, many other people in the field have published very consistent results.”
16 susceptibility genes linked to Alzheimer’s disease found
“People have used many ways to induce gamma, including sensory stimulation, transcranial alternating current stimulation, and transcranial magnetic stimulation, but the key is to deliver stimulation at 40 hertz. They all see beneficial effects.”
Since 2016, research led by Tsai has shown that 40Hz stimulation through light, sound, or vibrations can reduce Alzheimer’s related issues like amyloid and tau proteins, prevent neuron damage, and improve memory in mice.
Studies revealed how this stimulation triggers beneficial responses in various brain cells, including neurons and microglia. For instance, 40Hz stimulation helped mice clear harmful amyloid by activating the brain’s glymphatic system.
Human trials at MIT and Cognito Therapeutics have also shown promise. Participants exposed to 40Hz light and sound experienced slower brain shrinkage and some cognitive improvements. Cognito is now conducting a large phase III trial called GENUS to test this therapy further, aiming to make it a safe, noninvasive treatment for Alzheimer’s patients.
Tsai’s team and MIT colleagues Edward Boyden and Emery N. Brown have inspired global research into noninvasive gamma sensory stimulation as a potential therapy for Alzheimer’s. Numerous studies now support its benefits. For instance, in 2024, researchers in China confirmed that 40Hz sensory stimulation boosted glymphatic fluid flow in mice.
A 2022 Harvard study showed that 40Hz stimulation with Transcranial Alternating Current significantly reduced tau proteins in three out of four human participants. Meanwhile, a 2023 study involving over 100 people in Scotland found that audio-visual gamma stimulation (at 37.5Hz) improved memory recall.
Despite progress in research and clinical trials, there are still unanswered questions about how GENUS (Gamma Entrainment Using Sensory Stimulation) works.
Tsai’s team at MIT is investigating the cellular and molecular responses, focusing on systems like neuropeptides and how cells like microglia react to gamma stimulation and its effects on disease.
While a national phase III trial is underway, understanding these mechanisms could improve and expand the therapy’s potential. Tsai notes that deeper insights might optimize the treatment and reveal how it could benefit other neurological conditions, such as Parkinson’s, stroke, anxiety, epilepsy, and even cognitive challenges from chemotherapy or multiple sclerosis. Her lab is also exploring its possible benefits for Down syndrome.
Journal Reference:
- Jung M. Park, Li-Huei Tsai. Innovations in noninvasive sensory stimulation treatments to combat Alzheimer’s disease. PLOS Biology. DOI: 10.1371/journal.pbio.3003046
Source: Tech Explorist
