Sleep studies are tests that record what happens to your body during sleep. The studies are done to find out what is causing your sleep problems.

Sleep studies can also determine whether you have a problem with your stages of sleep. The two main types of sleep are non-rapid eye movement (NREM) and rapid eye movement (REM). Normally, NREM and REM alternate 4 to 5 times during a night’s sleep. A change in this cycle may make it hard for you to sleep soundly.