Multiple Sleep Latency Test (MSLT)
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Feeling tired all day, even after a full night’s sleep? The Multiple Sleep Latency Test (MSLT) helps uncover the cause behind excessive daytime sleepiness by measuring how quickly you fall asleep and whether you enter REM sleep too soon — key indicators of sleep disorders like narcolepsy.
This test goes beyond surface-level fatigue. It gives us a window into how your brain experiences sleep during the day — so we can move from symptoms to solutions.
This test goes beyond surface-level fatigue. It gives us a window into how your brain experiences sleep during the day — so we can move from symptoms to solutions.
What Happens During the Test
Conducted in a peaceful, controlled environment, the MSLT takes place over a full day and consists of five nap opportunities spaced apart by about two hours. During each, sensors record brain waves, eye movements, and muscle activity to identify how quickly you drift into sleep — and if your body skips the natural stages of rest.
Why MSLT Matters
- Pinpoints Sleep Disorders
Especially effective in diagnosing narcolepsy and idiopathic hypersomnia, where REM sleep occurs too early or sleep comes too easily. - Quantifies Sleepiness
Measures how long it takes you to fall asleep (sleep latency) across multiple sessions to assess true daytime drowsiness. - Builds a Better Treatment Plan
Results guide next steps — from further evaluation to medication or behavior-based therapy tailored to your needs.
What You’ll Experience
Your visit is designed to be simple, comfortable, and insightful. From start to finish, every part of the experience is tailored to help us learn more about your natural sleep patterns
Simple Structure, Valuable Insights
Five daytime nap trials, each up to 20 minutes long, every two hours. You don’t have to fall asleep in every one — both your ability and inability to nap provide crucial data.
Comfortable and Non-Invasive
There’s no overnight stay required after the test. Just arrive rested and stay relaxed. We take care of the rest.
Frequently asked question
Yes. Stimulants, antidepressants, sedatives, and other medications can interfere with your ability to fall asleep or enter REM. You may need to pause certain medications before testing under your provider’s guidance.
The MSLT mainly diagnoses narcolepsy and idiopathic hypersomnia. Other sleep disorders usually require different tests like polysomnography or actigraphy.
Yes, you can eat and drink between naps. Avoid caffeine and alcohol, as they may affect your ability to fall asleep.
SOREMPs are when you enter REM sleep very quickly after falling asleep. Having 2 or more SOREMPs during the MSLT is a strong indicator of narcolepsy.