BEIJING, May 27 (Xinhua) — According tomedia reports, Alzheimer’s disease is a neurodegenerative disease and is the most common form of dementia in the world. According to new research, in the future we may be able to treat the disease by watching TV. Every morning, Li-Huei Tsai, a Chinese-American biologist, meditates in front of a flashing screen. Synchronized with the flashing lights is a shrill click, a bit like an impassioned flamenco dancer tapping the clapboard. However, this rhythm is not intended for entertainment, but rather to keep the brain active.
The combination of flashing lights and clicks is designed to synchronize gamma waves, a special type of electrical activity in the brain. For the unsuspecting, this stimulation of light and sound may seem like the latest health fad, but from neuroscientists, there is evidence that it can prevent Alzheimer’s disease.
The new study offers a whole new way to prevent and treat the most common form of dementia. Today, dementia affects about 50 million people worldwide, and that number is expected to triple by 2050.
The most obvious neurological changes associated with Alzheimer’s disease are the accumulation of toxic amyloid plaques formed outside cells and the tangle of Tau proteins in neurons. Both seem to wreak havoc on our neurons and synapses, which are the bonds that neurons communicate with each other. It’s not surprising that Alzheimer’s research has focused on finding drugs to remove these plaques for the past 30 years, but we’re still waiting for breakthrough treatments.
Now, a host of new research suggests that e-therapy may be the answer to the problem, compared to chemotherapy. It all depends on the gamma-wave rhythm, which seems to trigger a clean-up operation in the brain that removes toxic substances before they cause damage.
Healing brain waves
Although we often use the word “brain wave” to describe the flash of inspiration, in neuroscience it describes a rhythmic electrical activity that is generated by a group of neurons in the brain discharged together at a specific frequency.
Neurons generate these currents through the flow of positively charged atoms on the cell membrane. Just as television and radio transmit radio waves over different frequencies, brain waves at different frequencies seem to be associated with specific neural functions. Gamma waves oscillate at frequencies of 30 to 100 Hz per second, which can usually be observed when we concentrate, or encode and retrieve memories.
Interesting studies in the early 20th century have shown that gamma waves in Alzheimer’s patients are particularly weak compared to healthy people whose cognitive abilities have not declined, suggesting that Alzheimer’s disease may be associated with a disorder of the brain’s rhythms. However, it is not clear whether this is just another result of neurodegeneration or a potential cause of neurodegeneration. Professor Cai’s team began to study the problem.
To reveal how this works, they first used a technique called optogenetics, in which neurons in laboratory mice were genetically modified to react to a particular color of light. By implanting a small light source in the skull, the team was able to stimulate gamma waves with incredible precision and observe its effects.
Cells that care for nerves
The team’s findings are shocking, revealing not only a significant reduction in amyloid plaques associated with Alzheimer’s disease, but also the possible mechanisms for the phenomenon.
Researchers are particularly interested in the effects of gamma waves on microglia cells in the brain. Small glial cells are a special class of glial cells that look like tiny, tentacle-scented marine organisms that act as brain care and security guards. “They’re like an immune monitoring,” says Prof. Cai. “
Previous studies have found that small glial cells in Alzheimer’s patients often fail to perform these duties. But in the new study, gamma waves appear to have reawakened them, reducing the level of amyloid plaques and tau protein entanglements. Moreover, the effect seems to be very rapid, and just one hour of stimulation is enough to activate small glial cells and significantly reduce the number of amyloid plaques.
Linking gamma waves in this way to the activity of these small glial cells has led us to make a huge leap forward in our understanding of Alzheimer’s and gamma wave function. However, optogenetic-stimulating treatments require genetic modification and surgery and cannot be easily applied to humans. So Professor Chua’s team went on to examine whether some of the less invasive brain-wave combination therapies had similar effects.
In one experiment, the researchers placed mice under lights and blinked for an hour at 40 Hz a day; Their idea is that in these cases, neurons in the visual and auditory systems begin to discharge in sync with light and sound signals, triggering brain wave activity that spreads throughout the brain. That’s what they see. As expected, with gamma wave enhancement, there was an increase in the activity of small glial cells and a decrease in toxic amyloid plaques.
Importantly, these differences were also seen in measurements of mouse behavior. The stimulated mice were more likely to learn to walk the maze, while other mice became more forgetful as they got older.
The biggest test, of course, will be whether scientists can replicate these results in real Alzheimer’s patients. Professor Cai Is currently beginning clinical trials to explore the long-term benefits of gamma-wave stimulation in humans. There is some exciting preliminary evidence that doing so can indeed improve cognition.
In a study led by Amy Clements-Cortes of the University of Toronto in Canada, tactile and auditory stimulation was used. Participants diagnosed with different stages of Alzheimer’s were placed on a chair with six speakers that made a low sound in the gamma wave band. Clements-Cortez points out that this effect is a bit like a “subwoofer” that makes patients feel a slight vibration throughout their body.
After six 30-minute training sessions, the subjects showed significant improvement in the standard tests of various cognitive abilities, including cardionumber and short-term memory. Mr Clements-Cortez said it was surprising to have achieved such an effect in such a short period of time. She also got the same results from another patient with early signs of dementia, who had been using similar devices at home for three years. “Three years later we went back and saw that her cognitive abilities remained basically the same, ” Clements-Cortez said.
Obviously, more evidence is necessary because the sample is large enough, but Clements-Cortez believes that these early results have been “very encouraging”. She says patients could even receive the treatment in the future while watching TV or listening to the radio.
Other researchers say that past Alzheimer’s research has gone through a lot of dead ends, and the prospect of this new treatment will be particularly welcome.
This approach may prove to be a particularly valuable early intervention. Many patients may already have cognitive difficulties, but diagnosis of Alzheimer’s can take a long time to confirm, which can lead to delays in treatment because patients are often reluctant to risk potential side effects before diagnosis. Any early intervention (for these patients) must be extremely careful and safe, and of all the ways you can think of, flashing lights or repeated sounds are the least invasive. In other words, at least for most people, this stimulation may not be suitable for people with epilepsy, as it can lead to seizures.
Barry McDermott, a researcher at the National University of Ireland, is equally optimistic about such early interventions. “No doctor will prescribe preventive anti-Alzheimer’s drugs to you, but these methods are available early on, ” he says. ” In theory, you can even install an app on your smartphone that is related to this. “
Despite the rapid progress so far, the researchers stress that there are still many questions to be answered. In addition to the need for stronger evidence to demonstrate the long-term benefits of clinical trials, the researchers need edgto sedatives and optimal treatment duration for gamma wave use. They point out that while it seems unlikely that patients will “overuse” gamma waves, it is also worth considering whether too aggressive the technology will have any adverse effects.
It remains to be seen whether gamma-wave stimulation will improve brain function in healthy people. Professor Chua is cautious, arguing that there is a threshold for gamma wave’s effects on the healthy brain, and she hopes that gamma wave can be used as a precautionary measure to protect brain function before any signs of cognitive decline begin to show up in middle age, “I think it’s possible.”
Although there are still many questions to be answered, Professor Cai has been experimenting with such devices himself. “I feel good, ” she would laugh. Like all scientists, Professor Chua is well aware that his personal experience should not be evidence, but if the study is successful, more people will start the day with similar sounds and lights to protect their brain function. (Any day)