Sleep studies help doctors diagnose sleep disorders such as sleep apnea, periodic limb movement disorder, narcolepsy, restless legs syndrome, insomnia, and nighttime behaviors like sleepwalking and REM sleep behavior disorder. Often these disorders cannot be identified with a normal office visit—your doctor needs to gather more conclusive evidence while you're asleep.
 
A sleep study is a non-invasive, overnight exam that allows doctors to monitor you while you sleep to see what's happening in your brain and body. 
 
The data from your sleep study will usually be taken by a technologist, and later evaluated by your doctor. This may take up to two weeks, when you'll schedule a follow up to discuss the results.