The statistics say that as you get older, the quality of sleep declines and the volume of prefrontal lobe that helps sustain quality of sleep declines.
A new study published in Nature Neuroscience suggests that the declining quality of sleep with age affects the ability to make new long-term memories.
The quality of sleep is a significant issue as we get older, the National Institutes of Health reports that over 50% of people over 60 years of age have sleep problems. This research indicates that the consequences are not limited to feeling tired during the day.
Here’s the gist of the research. As expected, brain scans of young and older adults found the prefrontal cortex to be about one-third smaller in the older subjects. Before bedtime, both groups studied a list of words paired with nonsense syllables, like “action-siblis” and “arm-reconver.” The use of nonwords was intended to get at new learning.
After studying, and before sleep, the young group outperformed the older subjects by about 25 percent. During sleep, the older people got only about one-quarter the amount of slow-wave, deep sleep that is believed to be critical to memory consolidation.
In the morning retest, the younger group outperformed the older group by 55%. The inference is that the lack of deep sleep impaired long-term memory.
One could argue that this study included a small number of participants and therefore does not justify any action.
A different position.
There are other negative effects of poor quality sleep. For example, even losing a few hours of sleep can turn your immune system against, you resulting in tissue damaging inflammation.
Statistically, sleep quality does declines with age, as does memory. But that’s averaging people together and does not get at factors that improve the quality of sleep, memory and even preserve brain volume. Nor does it account for the findings that in random samples of older people 20-30% perform memory test just as well as younger ones.
Can lifestyle negate all the impacts of biological aging? Probably not, but there is very encouraging evidence indicating that it can make a big difference.
According to the Mayo Clinic, Exercise during the day can help you fall asleep faster and deepen your sleep. Of course, we know that exercise is good for you cardiovascular system and helps control one’s weight. We also have evidence that brisk walking improves memory and the size of at least some regions of the brain involved in memory.
Improving the quality of sleep is one more good reason to exercise.
There is a growing consensus that it is the deep sleep that matters, not the traditional notion of eight hours. Naps that include deep sleep may be just as effective in memory consolidation and fostering creative thinking. We need a study that compares young and old subjects before and after naps, and one that measures deep sleep in the naps in both groups.
To learn more how lifestyle can improve quality of life, Download our paper, Everyday Ways to for A Rich and Extended Life