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Need a little non-invasive brain stimulation to boost your aging memory for that next big project, work meeting, or family gathering? A new study suggests that it could be
One study found that sending electrical currents to two parts of the brain known for storing and recalling information slightly improved immediate word recall in people over the age of 65. A study by the Boston University team published Monday in Nature Neuroscience.
Masud Husain, professor of neurology and cognitive neuroscience at the University of Oxford, said in a statement, “Whether these improvements occur in everyday memory, not just word lists, has yet to be tested. was not involved in the study.
Still, the study “provides important evidence that stimulating the brain with small amounts of electrical current is safe and can also improve memory,” says the Center for Alzheimer’s Disease Prevention at Florida Atlantic University Schmidt. Dr. Richard Isaacson, director of the clinic, said. Medical schools not involved in research.
Neuroscientist Rudy Tanzi, a professor of neuroscience at Harvard Medical School, who was not involved in the study, said the study participants with the poorest memory “believed to have mild cognitive impairment” had the most improvement. He said it was noticeable.
“There was a clear beneficial effect on immediate word recall in people with mild cognitive impairment,” said Tanzi, who is also director of the Department of Genetics and Aging Research at Massachusetts General Hospital in Boston.
“This preliminary but promising finding warrants further investigation of the use of bioelectronic approaches for disorders like Alzheimer’s disease,” he added.
Scientists believed that by some point in adulthood, the brain was fixed and unable to grow or change. Today, it is widely understood that the brain is endowed with lifelong plasticity (the ability to reorganize its structure, function, or connections).
Transcranial alternating current stimulation (tACS) attempts to enhance brain function with a device that applies wave-like stimulation. An electric current is passed through electrodes on the scalp to specific areas of the brain. Electromagnetic waves can mimic or alter brain wave activity to stimulate growth and hopefully alter the brain’s neural networks.
An alternative version that uses magnetic fields called transcranial magnetic stimulation (TMS) is approved by the US Food and Drug Administration to treat depression.
“We believe this is the future of neurological interventions, helping to strengthen brain networks that may be failing,” said Hofstra/Northwell University’s Zucker School of Neurology and Psychiatry. Dr. Gayatri Devi, Clinical Professor of Medicine, said. yoke.she wasn’t involved in anything new study.
“Additionally, treatment may be tailored to each individual based on that individual’s strengths and weaknesses, something that drug therapy cannot do,” Devi said.
New findings published in Nature Neuroscience show that brain cells are “activated at specific times, defined by the frequency of (electrical) stimulation,” says study co-author, Ph.D. Postdoctoral student Shrey Grover said. program at Boston University.
“The result of altering the timing of activation of brain cells is to trigger this process of plasticity, which allows effects to persist in time even after the stimulus has ended,” he says. added.
As the brain ages, it is common to lose some of its ability to remember. For some people, it may be short-term memory that suffers the most: Where did you park your car in the mall on this shopping trip? Others may have trouble remembering things over longer periods of time. No. Where did you park your car before you flew on vacation two weeks ago? Others struggle with both types of memory.
Researchers at Boston University slightly analyzed both long-term and short-term or working memory separately in two randomized experiments on 20 people between the ages of 65 and 88. In the experiment, 60 hertz gamma waves and 4 hertz theta waves were applied alternately. To two brain centers that play a key role in memory.
Gamma waves are the shortest and fastest of the brain wave frequencies, operating between 30 and 80 hertz, or cycles per second.some brain waves called high gamma waves Recorded up to 100 Hz.
The gamma wave brain is intensely and fully engaged. People under stress that require them to focus on the laser, such as when taking a test, solving a complex problem, or solving a difficult mechanical problem, can produce gamma waves.
Theta waves are much slower, ranging from 4 to 8 cycles per second. When you’re in Theta mode, you’re probably running on autopilot. We commute without thinking about our route, brush our teeth and hair, and even daydream. This is often the case when people ponder ideas or come up with solutions to problems. Studies have found that theta activity can predict learning success.
In the first experiment, a group received high-frequency (60 hertz) gamma waves in the prefrontal cortex just behind the eyes and forehead. As the center of learning and cognition, the frontal lobe helps store long-term memories.
Another group of 20 people received low-frequency (4 hertz) theta stimulation to the parietal cortex, the region of the brain just below where the ponytail sits. The parietal cortex is another part of the brain that lies above the hippocampus and plays an important role in learning and memory. People with Alzheimer’s disease often have atrophied hippocampus because tissue is lost and shrinks.
A third set of 20 individuals received a sham process that served as a control group.
Sessions occurred on 4 consecutive days. Each person took her 20-word recall test 5 times during the 20-minute stimulus each day. Subjects were asked to quickly recall as many words as possible at the end of each of the five tests.
The research team evaluated performance in two ways: How much of the last word on the list do participants remember just heard? It is a measure of short-term or working memory.How many words could you recall from the beginning of each list? The ability to memorize for a relatively long period of time.
Results showed that 17 of the 20 subjects who received high-frequency gamma stimulation improved their ability to recall words from the beginning of the word test. called long-term memory.
Similarly, 18 of the 20 participants who received low-frequency theta stimulation improved short-term working memory, the ability to recall memories. The last word I heard.
Compared to groups of people who received sham or placebo stimulation, those who received treatment said, “Older people remembered, on average, four to six more words from a list of 20 words by the end of four sessions.” The result was that Study co-author Robert Reinhart, director of the Institute for Cognitive and Clinical Neurosciences in Boston, said: University.
“It’s important to emphasize that this study primarily showed a small but significant improvement in short-term memory, but the test showed that words were recalled as early as a minute after learning them. It has not been shown to have a clear effect on long-term memory,” Tanzi said.
“Cognitive experts would say that remembering an hour ago is long-term memory,” added Tanzi. “However, when it comes to the clinical symptoms of Alzheimer’s and age-related memory impairment, we classify it as short-term memory. It means that
The study found that reversing the brain regions receiving theta and gamma stimulation in a second experiment had no effect. His third experiment with 30 people was conducted to validate previous results.
One month after the intervention, participants were asked to perform another word recall test to see if the improvement in memory persisted.
Overall, the results showed that low-frequency theta currents improved short-term working memory at 1 month, but high-frequency gamma stimulation did not. For long-term memory, it was the opposite, with gamma rather than theta performing better.
“We can independently improve short-term or long-term memory based on the spatial location and frequency of electrical stimulation,” explained Reinhart, an assistant professor in the Department of Psychology and Brain Sciences at Boston University.
This means researchers can tailor treatments to individual needs, Reinhart said.
What is it like? These devices are well tolerated and have few side effects.
“In an ideal world, the ultimate goal would be a portable home device that could deliver this therapy,” said director of the McKnight Brain Research Foundation, which funds research on the aging brain. says Isaacson.
“Currently, these treatments require specialized equipment, which is cumbersome, and can be time-consuming and costly,” added Isaacson. “Still, with limited treatment options for cognitive aging, which affects tens of millions of people, this is a promising step toward addressing symptoms and improving brain health.”
