Brain plaques are a common hallmark among Alzheimer’s patients. As abnormal clusters of protein begin to form, they build up between nerve cells. The protein that causes these plaques is known as amyloid-beta.
Researchers believe that these plaques are a major contributing factor in regards to cell death and tissue loss. This is also why so much of the available research has focused on amyloid-beta in terms of a potential treatment.
Most recently, it was not a drug that made the headlines, but rather the effects of a low-pitched noise. After showing promising results in mice, this potential intervention will now be tested in humans.
Study Finds — Low-Pitched Noise May Help Break Down Brain Plaques
While studying brainwaves, researchers can detect how alert and awake an individual feels. These brainwaves are essentially a major network of brain cells, firing in synchrony.
During sleep, for instance, brainwaves are slowest. When you are awake and alert, your brainwaves will be faster. The fastest brainwave, known as a gamma wave, is present when we make decisions, concentrate, or use our memory. For those who suffer from Alzheimer’s, these individuals produce fewer gamma waves. This is why scientists have turned to light and sound.
Researchers from the Massachusetts Institute of Technology found that while listening to low-pitched noise, such as a low-E note on the piano, this sound induced high-speed brainwaves. This, in turn, led to a breakdown of brain plaques associated with Alzheimer’s.
While studying mice, those who were exposed to low-pitched noise, showcased approximately half of the brain plaques associated with dementia. This reduction in plaques was found in regions that process sound — as well as in the hippocampus, an area that is associated with memory.
The same researchers had previously discovered positive results when flashing lights in the eyes of mice with Alzheimer’s. Now that they have observed a potentially new ‘noise treatment’ — the concept of noise therapy may be even more effective. It is also a more a practical form of potential therapy in humans.
- Researchers played noise with a 40 Hertz pitch. As mentioned, this is similar to the lowest E note on a piano. After exposing mice to this pitch, their brains were studied.
- Those exposed to these low-pitched noises, showcased fewer brain plaques.
- Although this effect may be stronger in mice, in comparison to humans, the safety of gamma-wave treatment is already being studied. The company, Cognito Therapeutics, will combine the effects of light, vibration and sound in twelve patients with either mild or moderate Alzheimer’s.
The Power of Brainwaves to Potentially Clear Alzheimer’s Plaques
As mentioned above, the researchers were previously interested in the relationship between Alzheimer’s-related changes and changes in gamma wave rhythms. They did this by using light. In December 2016, their findings were published in Nature, showcasing the effect of flickering LED lights on gamma waves.
What they found, was that this exposure stimulated gamma waves, resulting in reduced levels of amyloid-beta brain plaques. More specifically, LED lights were flickered at varying speeds. Following an hour-long treatment, beta-amyloid levels were reduced by half within the visual cortex of mice.
After 24 hours, the amyloid levels returned to normal. Upon completing this study, the researchers concluded that more research was required in order to determine how long these effects would last. They also stated that the function of gamma rhythms has been unappreciated within the past.
Ultrasound and the Human Brain
The relationship between sound and the brain of Alzheimer’s patients has been extensively studied in the past. From the benefits of music to the role of ultrasound, researchers continue to discover new connections.
Within one 2015 study, published in Science Translational Medicine, researchers from the Queensland Brain Institute studied the effects of focused therapeutic ultrasound. It was reported that by using this technique, 75 percent of the mice that they tested experienced fully restored memory function.
This was achieved by once again, removing amyloid-beta deposits. These effects were observed without any damage to the surrounding brain tissue. Treated mice also showcased improved performance on three memory tests — the novel object recognition test, the Y-maze, and the active place avoidance task. The researchers stated that ultrasound waves activate microglial cells, which then digest and remove amyloid plaques.
Now, fast forward to the spring of 2017. The same research team found that when combining ultrasound with immunotherapy, this potential treatment was even more effective. The researchers were able to reduce the toxic effects of beta-amyloid and tau with key antibodies. Once the immune system was triggered, these harmful proteins were targeted. These results were published in Brain.
In the past, these antibodies were not able to effectively cross the blood-brain barrier. When tested in vaccination trials, only 0.1 percent of therapeutic antibodies were able to enter the brain. This, of course, became far too costly.
It was this team’s research regarding ultrasound that provided a more effective solution. The ultrasound method temporarily created a gap in the blood-brain barrier, allowing antibodies to cross into the brain.
However, it is important to note that these effects have only been reported in mice, and may not apply to humans.