What is REM sleep?
Rapid eye movement (REM) sleep is the sleep stage in which dreams occur. One of the indicators of REM sleep is that your eyes move quickly back and forth behind the eyelids.
What happens during REM sleep?
Several changes to your brain and body happen during REM sleep that is different than other stages of sleep, including:
- Your breathing becomes quicker
- Your heart rate speeds up
- Your brain becomes more active, leading to dreams
- Most of your muscles are locked in place so that movement doesn’t occur while dreaming
- Your eye muscles become active, causing eye movements
Medically reviewed by
Dr. Colleen Ehrnstrom is a licensed clinical psychologist with a specialty practice in Acceptance and Commitment Therapy (ACT). Areas of expertise include insomnia and other sleep disorders, anxiety, and depression.
Dr. Ehrnstrom is not a medical provider and is not providing any recommendations regarding medications. Rather, she is sharing and reviewing the research as it relates to education when learning how best to treat insomnia.