Sleep Disorders Arousal During the Stages of Sleep By Brandon Peters, MD Brandon Peters, MD Facebook Twitter Brandon Peters, MD, is a board-certified neurologist and sleep medicine specialist. Learn about our editorial process Updated on April 28, 2022 Medically reviewed Verywell Health articles are reviewed by board-certified physicians and healthcare professionals. These medical reviewers confirm the content is thorough and accurate, reflecting the latest evidence-based research. Content is reviewed before publication and upon substantial updates. Learn more. by Jenny Sweigard, MD Medically reviewed by Jenny Sweigard, MD LinkedIn Jenny Sweigard, MD, is board-certified in internal medicine. She is an in-patient physician at Novant Health Huntersville Medical Center in North Carolina. Learn about our Medical Expert Board Print Arousal during sleep is caused by a change in the pattern of brain wave activity, as measured by an EEG. Arousal typically represents a shift from deep sleep to light sleep or from sleep to wakefulness. Astronaut Images / Getty Images What Is Arousal? As it sounds, arousal is when a person becomes ‘aroused’ or more alert to some extent during the sleep cycle. It is a change in brain wave activity. It does not necessarily mean waking up, but could just mean a shift out of extremely deep sleep to lighter sleep, from which it is easier to be woken up from. Change in Brain Wave Activity You might notice arousal during sleep. It is also measured by brainwave activity. Brain waves can be utilized to assess the level of consciousness or sleep stage of an individual, and thus can be used to measure arousal. A brainwave is the summation of the electrical activity of numerous neurons. Brain waves are typically recorded by an EEG, or electroencephalogram test. Alpha Waves and How They Help You Sleep Arousal Signifies Changes in the State of Sleep Arousal typically represents a shift in sleep states. Arousal can be a shift from deep to light sleep, or from sleep to a state of being awake. Sleep occurs in two basic states throughout the night. The two stages of sleep are rapid eye movement sleep (REM) and nonrapid eye movement sleep (NREM). Normally, you have several cycles of these stages throughout a typical night of sleep. REM is a deep stage of sleep with intense brain activity in the forebrain and midbrain. It is characterized by dreaming and the absence of motor function, with the exception of the eye muscles and the diaphragm. It occurs cyclically several times during sleep, but it comprises the smallest portion of the sleep cycle. The other basic state of sleep is nonrapid eye movement (NREM) sleep. Arousal occurs more often during states of NREM sleep, which consists of three separate stages. The three stages are N1, N2, and N3, and each separate state has unique, distinct, and recognizable electrical brain wave patterns. Stage 3 (N3) of NREM sleep is the deepest stage of sleep. Arousal can occur during any stage, and it is more common between stages What Can You Do About Arousal? Arousal is not uncommon during sleep, but most people fall asleep within a few minutes and don't remember it. Arousal, when you're trying to sleep, can become an issue if it occurs frequently. It can prevent some people from getting a solid night's sleep, and also from getting enough deep sleep. One important thing to keep in mind is that it is helpful not to worry about arousal. Keep in mind that it's normal, and stressing out about it can make it worse. Some ways to avoid prolonged arousal when you're trying to sleep include: Avoid caffeine for at least 8 hours before your bedtime. Keep yourself comfortable when you want to sleep by adjusting the light, noise, temperature, sleeping clothes, and blankets.Exercise is often suggested as a method to help eliminate excessive sleep arousal. Exercising during the day can tire out the body, and prepare it for a solid night's sleep, making you more likely to sleep through the night. If you are having persistent trouble sleeping, talk to your doctor. You might need a medical evaluation and treatment to help you sleep better. Overnight Sleep Study Testing: What to Expect Was this page helpful? Thanks for your feedback! Tossing and turning night over night can have a big impact on your quality of life. Our free guide can help you get the rest you need. Sign up for our newsletter and get it free. Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit 4 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Scammell TE, Arrigoni E, Lipton JO. Neural Circuitry of Wakefulness and Sleep. Neuron. 2017;93(4):747-765. doi:10.1016/j.neuron.2017.01.014 Herrmann CS, Strüber D, Helfrich RF, Engel AK. EEG oscillations: From correlation to causality. Int J Psychophysiol. 2016;103:12-21. doi:10.1016/j.ijpsycho.2015.02.003 National Institute of Neurological Disorders and Stroke. Brain Basics: Understanding Sleep. Passos GS, Poyares DL, Santana MG, Tufik S, Mello MT. Is exercise an alternative treatment for chronic insomnia?. Clinics (Sao Paulo). 2012;67(6):653-60. Additional Reading Patel AK. Physiology, Sleep Stages. StatPearls [Internet]. October 2018.