Polysonogram (PSG)

Polysomnography, known as a sleep study, is a test used to diagnose sleep disorders. Polysomnography records your brain waves, the oxygen level in your blood, and your heart rate and breathing during sleep. It also measures eye and leg movements.

Sometimes you may be able to do the sleep study at home. Home sleep apnea tests are used to help diagnose obstructive sleep apnea.

If you are doing a sleep study from home, there are different types of devices that may be used. Each device uses a different combination of sensors. Home sleep apnea tests generally record your breathing rate and airflow, as well as oxygen levels and heart rate. One style also includes information on blood vessels.

Polysomnography monitors your sleep stages and cycles. It can identify if or when your sleep patterns are disrupted and why.

Your health care provider may recommend a sleep study if it is suspected that you have:

• Sleep apnea or another sleep-related breathing disorder.
• Periodic limb movement disorder.
• Narcolepsy
• REM sleep behavior disorder.
• Unusual behaviors during sleep. This includes walking, moving around or rhythmic movements during sleep.
• Unexplained long-lasting insomnia. People with insomnia have trouble falling asleep or staying asleep.