Study Identifies Type of Sleep Needed to Help Decrease Anxiety Levels
Many anxiety disorders can negatively affect sleep, and poor sleep can increase feelings of anxiety, resulting in a vicious cycle. A new study suggests that non-REM slow-wave sleep is the stage of sleep needed to calm the brain and reduce anxiety, and that poor sleep may result in up to a 30% increase in anxiety the following day.
For their study, researchers from University of California, Berkley used functional MRI and polysomnography to scan the brains of 18 young adults. The scans took place while the participants watched emotionally stimulating videos after a full night of sleep and then again after a poor night of sleep. The State-Trait Anxiety Inventory questionnaire was used to measure anxiety levels following each viewing session. The researchers conducted a second, identical intervention with 30 additional participants.
The researchers also administered an online study. During this study, 280 participants recorded quality of sleep and anxiety levels for four consecutive days.
Results from the first two phases of the study showed that anxiety levels decreased significantly after a full night of sleep. Anxiety levels decreased the most in participants who obtained more non-REM slow-wave sleep. The brain scans showed that, after a sleepless night, a shutdown occurred in the area of the brain that normally helps regulate anxiety.
The online portion of the study revealed that even small reductions in sleep over a few nights resulted in increases in anxiety on the following days.
The study was published on November 4, 2019 in the journal Nature Human Behaviour.