Electrical stimulation of memory
Electrical stimulation improves working and long-term memory in the elderly
As we get older, it becomes more difficult for us to remember something. Researchers from Boston University report that daily twenty-minute electrical stimulation of the brain for four consecutive days shows an improvement in memory in older people for at least one month. Based on the interpretation of the results of the study, the authors believe that this non-invasive procedure is probably useful for improving both operational and long-term memory.
For the study, the scientists used transcranial alternating current stimulation of certain areas of the brain. They invited 150 people aged 65 to 88 to the laboratory, who were asked to memorize and recall lists of English words. At the same time, an electric current was supplied through electrodes in a cap worn by the participants. This current, according to neuroscientist Robert Reinhart, who led the study, enhances the natural biological processes of the brain during memorization and recall.
"People reproduced this process for 20 minutes daily for four days, and then we tested their ability to remember and recall words after a month without using electricity," Rinehart reports. — Participants showed improved memory on the second or third day. [They] could memorize and recall more words than usual, and this improvement could be noticed even after a month."
The researchers also noted that participants who started with the lowest cognitive scores benefited the most from brain stimulation. The researchers published the results of the study in Nature Neuroscience.
Rinehart and his colleagues targeted specific areas of the brain related to working and long-term memory, based on available research. They found that low-frequency (4 hertz) pulses in the parietal cortex improve the memorization of words from the end of lists, that is, in their interpretation, working memory. This type of memory showed particular improvements on the third and fourth days, as well as a month later. To improve long-term memory, the researchers affected the dorsolateral prefrontal cortex at a higher frequency, 60 Hz. In this case, the participants showed the best memorization of words at the beginning of the lists on the second, third and fourth days and a month later. In both cases, the results of the experimental groups were compared both with their results at the beginning of the study, and with the results of the control group, the electrical stimulation of the participants of which was only simulated.
According to Rinehart, the results suggest that different rhythmic patterns of activity in different areas of the brain are required to store information for short or long periods of time.
The World Health Organization estimates that by 2050 there will be more than 2.1 billion people over the age of 60 in the world, more than twice as many as in 2020. Over the same period, the world population aged 80 and over will triple to 426 million people. Cognitive decline is inevitable with age, but as life expectancy increases and, accordingly, the number of elderly people around the world increases, it becomes an increasingly urgent problem. And scientists are persistently looking for technologies to sustainably improve or protect memory function in the elderly.
Rinehart admits that the study does not close many questions. "We need to determine," he explains, "whether these memory improvements extend to different types of memories, such as visual or spatial memory, and whether they can be observed in tasks other than free memory. We also need to examine whether these improvements persist for longer periods of time and whether they lead to meaningful improvements in people's actual functioning." Further research will also be needed to find out whether such a technique can help people with brain disorders and those at risk of developing dementia.
Article by Grover et al. Long-lasting, dissociable improvements in working memory and long-term memory in older adults with repetitive neuromodulation are published in the journal Nature Neuroscience.
Portal "Eternal youth" http://vechnayamolodost.ru