A follow up on an article first published in March 2019 in Cell shows clumps of harmful proteins that interfere with brain functions of mice have been partially cleared using only light and sound. Testing hasn’t been done on humans yet, but this could play a major role in treating Alzheimer’s, dementia and Parkinson’s disease.
Led by a team of researchers that included MIT’s Picower Institute for Learning and Memory, they used strobe lights and a low pitched buzz. Studies showed this combination was able to remove plaque and recreate brain waves that had been previously lost.
The brain waves of mice and humans are known to work differently, so it’s no guarantee that it will also work on humans, but this for sure shows promise. The subjects have not shown any adverse side effects to date.
During a previous study, scientists used only light, by flashing it 40 times per second into the eyes of mice. This time around they added in the sound therapy as well and found that it dramatically improved their results.
Li-Huei Tsai, a researcher from MIT commented;
When we combine visual and auditory stimulation for a week, we see the engagement of the prefrontal cortex and a very dramatic reduction of amyloid.
There have also been previous studies investigating sound and whether or not it can play a role in treating Alzheimer’s. Sound was used to try and clear the brain of clumps of tau, amyloid proteins, and tangles associated with the disease. Ultrasound was used and showed it was able to make the blood vessels “leaky”, which encouraged improved function of the nervous system’s waste-removal experts, microglia.
Tsai went on to comment about his study from a few years ago: “The result was so mind-boggling and so robust, it took a while for the idea to sink in, but we knew we needed to work out a way of trying out the same thing in humans.”
Tsai decided to focus on gamma-frequencies, which move at a pace of 30 to 90 brain waves per second, and they are most active when we are paying close attention or searching our memories. In his previous study, Tsai suggested these gamma waves, which are impeded in Alzheimer’s patients, may play a pivotal role.
These gamma waves respond to both light and sound. For this study, rather than use a high pitch scream from an ultrasound, Tsai used a low droning noise of 40 Hertz, which is just barely audible to humans.
They exposed the mice to this sound for one hour every day for one week. This ended up leading to a significant drop in the amyloid build up within the auditory regions, along with stimulating the microglial cells and blood vessels.
Unexpectedly, this therapy also helped to clear up the nearby hippocampus, which is an important section of the brain associated with memory. This also led to improved cognitive function from the mice.
When light therapy was added into the mix, the scientists saw dramatic results. The combination of light and sound cleared plaques from several areas in the brain, including the prefrontal cortex. The researchers said the trash-clearing microglia also went into high gear.
These microglia just pile on top of one another around the plaques, said Tsai.
This is an exciting revelation and if trials performed on humans prove to be as successful as the mice, then it will not only be a cost-effective way to treat the disease but much better than hopping people up on a bunch of pharmaceutical drugs.
