Why REM Sleep is (Even More) Important Than You Think

Man sleeping photo via Shutterstock

As if you needed another reason to get to bed earlier, researchers at Boston University School of Medicine (BUSM) discovered that a group of cells in the brainstem that are activated during deep sleep (REM)—when dreaming happens and muscles shut down—is an integral part of correctly regulating emotional memory processing.

During REM sleep, the glutamatergic cells are activated in the brainstem, sending out phasic pontine waves, or P-waves. The BUSM researchers found in the study, which was published in the Journal of Neuroscience, that the presence of these P-waves is an important part of regulating fear and anxiety, meaning the study’s results could be key in developing treatments for anxiety disorders like PTSD, recurring fear, and panic attacks.

In the study, the researchers explored the role sleep plays in controlling stress and anxiety after traumatic experiences, and the fact that not getting enough REM sleep after such traumas often leads to anxiety disorders. Further, sleep is a vital part of ensuring the success of exposure therapy, a commonly-used treatment in which patients are carefully re-exposed to whatever is causing them fear of anxiousness so as to create an “extinction memory,” a thought that replaces or competes with the original disturbing memory.

With all this in mind, the BUSM team observed patients’ brains during extinction therapy to observe which brain activity resulted in successful exposure therapy. They found that, in the 57 percent of participants who successfully maintained an extinction memory after a day, P-wave activity was high, whereas in the subjects whose extinction memories failed, there was no P-wave activity. In a report from BUSM, the study’s lead author Subimal Datta says:

“The study results provide direct evidence that the activation of phasic P-wave activity within the brainstem, in conjunction with exposure therapy, is critical for the development of long-term retention of fear extinction memory,” said Datta, who also is a professor of psychiatry and neurology at BUSM. In addition, the study indicates the important role that the brainstem plays in regulating emotional memory.

More studies will need to take place to determine exactly how REM sleep-induced P-waves can be harnessed to treat anxiety disorders, which affect about 40 million people nationwide. But whether you have an anxiety disorder or not, the study seems like a great reason to get your eight hours of sleep a night.