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Due to a recent surge in pediatric RSV and flu, we are allowing only visitors 18 years of age and older in our general inpatient (hospital) settings at this time for the safety of our patients, in line with Illinois Department of Public Health guidance. Read More

Multiple Sleep Latency Test


The Multiple Sleep Latency Test determines excessive daytime sleepiness and is often used to diagnose narcolepsy. The test measures brain waves (EEG), eye movements (EOG) and muscle activity from the chin.

What to Expect        

Plan to spend the entire day. The Multiple Sleep Latency Test consists of four naps, beginning at two-hour intervals. You may sleep for only 15 minutes if you fall asleep. If you do not fall asleep, the nap will last 20 minutes.

What to do prior to the Multiple Sleep Latency Test

Most patients will require polysomnography the night before their MSLT