One of the best ways to treat anxiety?

Interestingly, variations in the anxiety levels of the well-rested group appeared to correlate with the amount of slow-wave sleep that the participants experienced the night before. This period of sleep appears to regulate these brain regions, ensuring that they operate in a balanced way.

“People with anxiety disorders routinely report having disturbed sleep, but rarely is sleep improvement considered as a clinical recommendation for lowering anxiety,” Simon said. “Our study not only establishes a causal connection between sleep and anxiety, but it identifies the kind of deep NREM sleep we need to calm the overanxious brain.”

While the study examined people who got no sleep whatsoever, poor sleep also seems to have similar anxiety-inducing effects. The researchers additionally tracked 280 other individuals, asking them to rate the quality of their sleep the night before and their level of anxiety the next day. Over the course of four days, participants consistently reported higher anxiety after a night of poor sleep, reporting that even minor changes affected their anxiety levels.