“Then downstream of that are all these beneficial effects.”Īll of this is still at the level of speculation. “This could be like resetting the mice every day and correcting some of this abnormal activity that they have,” he says. By providing the brains with a steady and regular beat, the repeating light and sound might work as a kind of metronome for brain activity. One possible explanation for this is brains with Alzheimer’s have irregular, often hyperactive, neurons, says Jorge Palop, a neurologist at the University of California, San Francisco, who did not work on the study. It’s not a drug or an antibody or anything, it’s just light and sound.” “This is the first time we’ve seen that this noninvasive stimulation can improve cognitive function. Mice that saw the light and heard the sound spent about two thirds of the time that untreated mice did examining the familiar object. “That shows some memory problems,” Tsai says. In one, where the mice were given a familiar and an unfamiliar object to explore, mice that didn’t get the treatment acted as though they’d never seen the familiar object. That showed when Tsai put the mice through a set of cognitive tests. And there was about a 40 or 50 percent decrease in amyloid and tau levels. “These are the learning and memory centers of the brain. “This was one of the big jumps in the new paper,” Macauley says. When the mice sat in a room with both the flashing light and the droning sound for an hour day, seven days in a row, amyloid plaques and tau tangles began falling in not just the audio and visual cortices but the prefrontal cortex and the hippocampus as well. To get these effects to penetrate deeper into the brain, she added a clicking sound like a dolphin’s chirrup that also had a 40-hertz frequency. This clearing-out process only happened in the visual cortex where the brain processes light information. They’re impaired in Alzheimer’s disease, but seems to restore their abilities.” These are the brain’s immune cells that clear cell debris and toxic waste including amyloid. “The light flicker stimulation triggers a tremendous microglia response. “It was the most remarkable thing,” Tsai says. When Tsai dissected the mice brains afterward, the amount of amyloid plaques and tau tangles in the mice that saw the light had plummeted. So when Tsai tuned her light to flash 40 times a second, or 40 hertz, and flickered it at the mice, their brains flickered back-generating gamma waves at a corresponding 40 hertz. Neurons encode our thoughts and actions and senses in this rhythmic electrical flutter. Brain waves are generated when large groups of neurons oscillate on and off together. In 2015 neuroscientist Li-Huei Tsai, director at The Picower Institute for Learning and Memory at Massachusetts Institute of Technology, was working on an experiment to manipulate that brain activity by flashing a white light at these mice. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today. If you're enjoying this article, consider supporting our award-winning journalism by subscribing. All the mice also had a third hallmark of the disease-irregular brain activity in the gamma range of brain waves that oscillate between 30 and 100 times a second. Another batch of the mice developed amyloid beta plaques-sticky heaps of protein that dam the flow of communication between neurons. One batch of mice formed neurofibrillary tangles inside their neurons-dysfunctional knots of a protein called tau that can lead to the cell’s death. The work was done in mice with genetic alterations that doomed them to develop key symptoms and pathology of Alzheimer’s disease. Still, all this is a big if, Macauley acknowledges.

It’s noninvasive and easy and low cost, potentially, so if it were to come to fruition in humans-that’s fabulous.” “I think it’s an absolutely fascinating paper to be honest,” says Macauley, who was not involved in this work. But new research is looking beyond drugs to see what relief might come from a simple LED light and a speaker.īathing patients in flashing light and pulsing sounds both tuned to a frequency of 40 hertz might reverse key signs of Alzheimer’s in the brain, according to a paper published in Cell on Thursday.

Virtually all new treatments have failed in clinical trials. “We really don’t have much to offer people,” says Shannon Macauley, a neuroscientist at Wake Forest School of Medicine. Although a few drugs manage temporarily certain cognitive symptoms of the illness, none can stop or meaningfully slow its progression. There is no cure for Alzheimer’s disease.

Binaural beats 40 hz