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  • The Sound Sleeper

Don't forget to sleep and improve your memory

You might think not much is happening when you’re asleep, but your body is actually hard at work.

Some of the behind-the-scenes processes that occur while we sleep involve memory — specifically, preparing our brain to learn and retain information.
Getting a full night of uninterrupted sleep — seven to nine hours — is important because different activities occur during various parts of our sleep cycle. The first two stages (both light non-rapid eye movement or NREM sleep) and the third (deep NREM sleep) prepare the brain to learn new information. Scientists say that interrupting the duration and quality of sleep can reduce our learning abilities by as much as 40%.

Memory consolidation
Memory consolidation, the process of cleaning out unnecessary information and preserving key memories — occurs during sleep’s third (NREM) and fourth (REM) stages. This is where connections are built between different pieces of information, with new learnings linking to previous memories. Sometimes these linkages happen in unexpected ways, boosting our problem-solving and creative abilities.
During sleep, we cycle through these four stages four to six times a night, repeating the full cycle about every 90 minutes — another reason we shouldn’t shortchange our sleep.

The right balance
While it makes sense that getting less than optimal sleep results in a fuzzy memory, does getting extra sleep — beyond 9 hours a night — supercharge our memory? Unfortunately, no. A recent study found that individuals with extreme sleep duration on either end (less than four or more than ten hours per night) experienced a decline in cognitive function compared to the group that slept seven hours a night.

While it may not seem like a big deal to occasionally lose sleep, research shows that sleep deprivation can have a lasting effect on the brain even after one night of poor sleep. In a 2018 study, brain scans of healthy adults before and after a night of sleep deprivation showed a significant increase in the proteins associated with memory loss and Alzheimer’s disease.

A different study found those sleeping less than six hours a night have more memory problems than those clocking at least seven hours.
Use sleep to your advantage: avoid self-defeating late nights and make a good night’s sleep a priority.

Bottom line
Use sleep to your advantage: avoid self-defeating late nights and make a good night’s sleep a priority.

Sources: Sleep Foundation; Ma, Y et al. (2020) Association between sleep duration and cognitive decline, JAMA Netw Open; Shokri-Kojori E et al. (2018) β-amyloid accumulation in the human brain after one night of sleep deprivation, PNAS; “Sleep On It.” NIH News in Health, May 2017; Winer JR, et al. (2021) Association of short and long sleep duration with amyloid-β burden and cognition in aging, JAMA Neurol.

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