Sleep Secret Revealed: The Brain Is Flipping Through a Memory Gallery in REM Sleep

Aug 26, 2015, by Dr. Becky Coats

We know that REM (rapid eye movement) sleep is vital to many of the essential restorative functions of sleep, which is part of why sleep apnea is so disruptive to the body’s system–it prevents the brain from staying in–and sometimes from even reaching–REM sleep.

Unfortunately, we don’t fully understand just why REM sleep is so important. Now researchers think they have discovered a part of the answer to that problem: the brain seems to be flipping through images during REM sleep.

Seeing Inside the Brain

REM Sleep SecretsIt’s hard to know what’s going on during sleep because we can’t very often get inside the brain during sleep. But sometimes we get the opportunity to do just that, as in this case. Often, people who are going to have brain surgery to stop epileptic seizures have to undergo brain monitoring before the procedure. This involves the placement of electrodes inside the brain for ten days. Researchers could then look at the data from inside the brain alongside less invasive measures, such as eye motion tracking, muscle tone measurements, and electroencephalograms (EEG), which are often used to identify the different stages of sleep.

Researchers from Tel Aviv University and UCLA discovered that during REM sleep, the eye motions correlated with activity in the medial temporal lobe. This part of the brain has already been associated with the processing of familiar images, such as known celebrities or famous places. Each eye motion was accompanied by a new burst of activity in the region, as if the brain were looking at a new picture.

This makes researchers believe that the brain might be flipping through memories the way we might swipe through a gallery of pictures on our smartphones.

Support for a Dream Theory

Our most vivid dreams occur during REM sleep, and this new research supports one theory about why we dream. If our visual memory center is being stimulated during sleep, it’s likely that dreams are actually related to the process of encoding memories, possibly moving them from short-term memory to long-term memory storage.

This also might explain one of the negative impacts of sleep apnea. When people have sleep apnea, which disrupts or prevents REM sleep, they often suffer memory problems along with cognitive problems and emotional difficulties. They also stop being able to remember their dreams (though mild to moderate sleep apnea sufferers often report an increase in nightmares, possibly related to their suffocating sensations).

If you’re looking for sleep apnea treatment in Dallas, please call  for an appointment with a sleep dentist at Grapevine Dental Care.