New Research Suggests This Is How Our Memories Are Stored During Sleep

Sleep helps us manage our mental health and ward off chronic disease (via the University of Michigan School of Public Health). Sleep might seem like a passive activity, but according to a recent study in the journal Proceedings of the National Academy of Sciences, our brain is busy processing the events of the day into our long-term memory. Researchers at the University of Pennsylvania developed a learning algorithm to simulate what goes on in the brain during sleep.

While we're awake, the hippocampus keeps track of various episodes of our day. The neocortex, which is involved with our long-term memory, is somewhat active in processing our environment. During non-REM sleep, the hippocampus teaches your neocortex what happened during the previous day by playing back certain episodes. Then, the brain enters REM sleep, where the neocortex integrates these events with old information in memory. This is how your brain works to consolidate everyday events into your memory.

In a news release about the research, study author and University of Pennsylvania neuroscientist Anna Schapiro said the results aren't necessarily new, but they reiterate the need for experimental research. "We still need to test this," Schapiro said. "One of our next steps will be to run experiments to understand whether REM sleep is truly bringing up old memories and what implications that might have for integrating new information into your existing knowledge."

The study's computer simulation was based on a healthy adult getting a good night's sleep. The news release also said that future research could help treat sleep-deprived people with psychiatric and neurological disorders.

According to the Harvard Medical School, sleep-deprived people lack the focus and attention to fully engage in their waking lives. Because our events in waking life are consolidated during sleep into memory, this process is disrupted without adequate sleep. Not only that, but our overworked brains have problems accessing our long-term memory while we're awake. When we deprive ourselves of sleep, we have difficulty making accurate judgments of everyday situations in our lives.