People have always underrated sleep, despite it playing an integral role in memory creation, as well as shifting from short-term to long-term memory. When people deprive themselves of or are unable to sleep, then memory consolidation is impeded.
This is particularly true for older adults, according to the research team, who published their findings in the journal Neuron. They discovered that older brains tend to forget more because their brain struggles with, and sometimes loses, coordination with two brain waves that are important to memory formation.
"It's like a drummer that's perhaps just one beat off the rhythm," explained Matt Walker, a co-author of the study and a professor at UC Berkeley. "The aging brain just doesn't seem to be able to synchronize its brainwaves effectively."
For the study, around 50 participants made up of both older and young adults were asked to learn at least 120 pairs of words before they slept. Electrodes were then placed on their heads prior to sleeping to monitor the electrical waves that the brain makes during deep sleep. In particular, they studied the interaction between slow waves and faster waves, called sleep spindles, to determine the participant's recall was in the morning.
"When those two brain waves were perfectly coinciding, that's when you seem to get this fantastic transfer of memory within the brain from short-term vulnerable storage sites to these more permanent, safe, long-term storage sites," Walker explained.
Results indicated that brain waves of younger adults were "in better sync," and they were able to remember more word pairs after waking up. Older adults, however, had less synchronized brain waves during deep sleep and remembered fewer word pairs the next morning.
Moreover, the researchers discovered that older adults had developed brain atrophy in the area that is involved with deep sleep. People who had more atrophy produced less rhythm in the brain.
Brain atrophy, or the shrinking of the brain as a result of the loss of neurons, is a normal consequence brought about by aging. Studies have stated that brain weight decreases by about five percent per decade from age 40, which may speed up once the person reaches 70 years of age. Researchers also believe that this is what causes the loss of synchronization and rhythm in deep sleep. (Related: A sound sleep may be a solid defense against memory loss and Alzheimer's disease.)
Still, the study shines hope on the possibility of improving memory loss by "resynchronizing" brain rhythms during sleep. This will give brain waves a needed push and make it easier for older adults to improve their brain rhythm during deep sleep. This will be the focus of further studies of the subject in the future.
Aside from sleep, there are other factors to prolonging brain function and minimizing the rate of decrease. Diet has been studied and proven to play a part in protecting against cognitive decline. In particular, increasing the intake of fish and seafood have been known to protect against stroke. Exercise is also known to help with maintaining the brain's grey and white matter, as well as increase its executive functioning. Additionally, the effect of intelligence and environmental factors – like education and occupation – has been known to protect against cognitive decline as well.
To learn more about the relationship between sleep and brain function, head over to Brain.news today.
Sources include:
Please contact us for more information.
