Tracking this activity during a sleep study can help your doctor diagnose and treat a variety of sleep disorders including sleep apnea and restless legs syndrome and can serve as an evaluation for certain causes of excessive sleepiness says johns hopkins sleep expert sara benjamin m d. If your doctor suggests you undergo a sleep study or polysomnography you may be wondering what is involved in this test and what to expect. Overnight Sleep Study Testing What To Expect Sleep Apnea When you arrive for your sleep study you will be met by a registered polysomnographic technologist rpsgt who will be administering your sleep study. What happens during a sleep study for sleep apnea . If your doctor has referred you to a lab to take a sleep test chances are you re a chronic snorer you have symptoms of sleep apnea for instance you temporarily stop breathing during the night or you feel sleepy during the day even after a full night in bed. Learn more about how a sleep study works what it help...