The changing sleep patterns of older people may have something to do with their forgetfulness, according to a new study.
A team from the University of California, Berkeley conducted a research to see how brain rhythms during sleep can impact memory loss. The study paper was published in the Neuron journal.
The researchers found that there is less coordination among two brain waves, which are crucial for retaining new memories, in older people when they are in deep sleep.
"It's like a drummer that's perhaps just one beat off the rhythm," said study author Matt Walker. "The aging brain just doesn't seem to be able to synchronize its brainwaves effectively."
Less Coordination Among Slow And Fast Sleep Waves
The study findings seem to throw light on a long-puzzling question about how getting older can impact the memory of even those not affected by a brain disease or mental condition like Alzheimer’s.
According to Walter, the research was the consequence of an effort to gain insight into how the slumbering brain changes short-term memories into those that can remain for the entire life. The researcher was curious to know what is that quality about sleep that cements new facts into the brain’s neural architecture.
Conducting The Research
To conduct the research, the team carried out an experiment on 20 young adults who were made to memorize 120 pairs of words. The researchers then put electrodes on the heads of the volunteers and had them go to sleep.
The electrodes allowed the research team to observe the electrical waves generated during deep sleep by the brain. They observed how slow waves, which are generated every second, interacted among themselves. Faster waves called spindles, which take to occur over 12 times per second, were also focused on.
The participants took a test the next morning to find out the number of word pairs they could recall. The research team found that the volunteers’ performances were influenced by how well their spindles and slow waves were in synchronization during a deep slumber.
The team then carried out the same experiment with 32 volunteers in the 60s to 70s age group and found their brain waves to be less in synchronization during a deep slumber. The older participants also could recollect a lower count of word pairs the next day and their performance, too, was determined by how the brain waves had synchronized.
The researchers also detected a possible cause for the age-related lack of coordination. It was atrophy of a brain area, which is a normal consequence of aging, that was involved in generating deep sleep. People with higher atrophy had less brain rhythm.
Julie Seibt, sleep and plasticity lecturer at U.K.’s University of Surrey, said that the study is the first of its kind that detected a cellular mechanism that might be impacted during aging, thereby be the cause for lack of memory consolidation during sleep.
Seibt, who is not attached with the study, also added that to confirm the findings, the research team will have to show that memory problems can be caused in a young brain by disturbing these rhythms.
