Sleep Testing



Polysomnography (PSG) is a study of sleep cycles and sleep behavior. It is usually done in a sleep center overnight. This study involves observing a person at sleep while charting brain waves and other body functions.

Possible Complications

There are no major, lasting problems from having this test.



This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

Edits to original content made by Denver Health.

a (Polysomnogram; Overnight Sleep Study; Rapid Eye Movement Studies)


American Academy of Sleep Medicine 

National Sleep Foundation 


Better Sleep Council Canada 

Canadian Sleep Society 


Kushida CA, Littner MR, et al. American Association for Sleep Medicine practice parameters for the indications for polysomnography and related procedures: an update for 2005. Sleep. 2005 Apr;28(4):499-521.

Polysomnography. EBSCO DynaMed website. Available at: Accessed March 22, 2021.

Sleep studies. National Heart, Lung, and Blood Institute website. Available at: Accessed March 22, 2021.

Sleep studies: In the sleep laboratory and in the home. American Thoracic Society website. Available at: Updated 2015. Accessed August 22, 2018.

What is a sleep study? Boston Children’s Hospital website. Available at: Accessed March 22, 2021.