Multiple Sleep Latency Test FAQs

Before the Study

What is a sleep study and a Multiple Sleep Latency Test (MSLT)?

For most patients, a sleep study is a key diagnostic component of a sleep disorder evaluation. A sleep study, also called a polysomnogram (PSG), measures your brain wave activity, eye movements, muscle contractions, heart activity, breathing and blood oxygenation during sleep.

Also called a “Nap Test”, the multiple sleep latency test (MSLT) is the standard way to quantify sleepiness and diagnose disorders of excessive sleepiness. After being asked to try to fall asleep for each nap test, sensors on the head and chest record your brain wave activity, eye movements, muscle contractions, and heart activity to accurately detect if you fall asleep.

The information we collect during your study is reviewed and analyzed by our sleep specialists.

Can I visit the center before the study?

Yes, tours of the sleep testing laboratory are provided during the day. Please feel free to call us to schedule a daytime tour before your test. We will be happy to accommodate your visit. You are also welcome to take a tour during your scheduled appointment.

What information will I get ahead of time?

Once you have scheduled your sleep study, you will receive a welcome package either in the mail or via email containing forms you need to complete, along with directions and phone numbers to the facility. Be sure to bring the directions, phone number, completed forms and your health insurance card on the night of your study.

Will I have a private bedroom?

Yes, sleep study bedrooms are private.

What personal items should I bring?

In addition to 2-piece nightclothes, you will need regular clothes to change into in the morning. The purpose of the test is to see how sleepy you are on a typical day, so you need to wear daytime clothing for your naps. You should also bring something to keep you occupied during the day (videos, reading materials, laptops, etc.), and any toiletries you may need if you would like to shower before you go home.

What if I have special needs?

Please call our office between 9:00 a.m. and 5:00 p.m., Monday through Friday to discuss your special needs requirements. We will try to accommodate your needs and answer any questions you may have about the sleep study procedure.

What about medications?

Please take your medications as usual and bring them to the center, if necessary. Upon arrival at the sleep lab, the technologist will be able to tell you your approximate bedtime so that you may take nighttime medications accordingly. Our staff will not be able to dispense any medication to you.

We also recommend that you discuss with your physician whether your medications will affect the sleep study results.

On the Morning of the MSLT

What should I expect during the study (after your overnight PSG)?

A technologist will remove sensors from your nose, torso, finger and legs. The electrodes on your head, face, and chest will remain on. A daytime technologist will introduce himself or herself to you and explain how the test will proceed. You will be asked to change into daytime clothing. You will also be instructed to stay off the bed in between nap tests.

When will I wake up?

If you are not already awake you will be awakened after 9 hours of testing.

Will I be able to take a shower in the morning?

No. You will still have wires attached to your head, face and chest.

Will breakfast and lunch be provided?

The center does not provide meals, however most centers do have a kitchen with refrigerator and microwave, as well as a hot/cold spring water dispenser. You are welcome to use the kitchen or ask your sleep technologist for assistance. Please bring your lunch or money to order a take-out lunch from a local sandwich shop.

During the MSLT

What happens during the MSLT?

The MSLT consists of multiple nap opportunities with breaks lasting for two hours in between them. The first nap trial begins between 1-1/2 and 3 hours after you wake up from the overnight sleep study. You will be asked to eat a light breakfast at least one hour before the first nap trial.

For each nap trial, you are asked to lie quietly in bed and try to go to sleep. Then the lights are turned off. Once the lights are out, the test will measure how long it takes you to fall asleep.
After sleeping for 15 minutes, you will be awakened. Each trial will end if you do not fall asleep within 20 minutes. Between nap trials, you will have to stay out of bed and occupy yourself so that you remain awake.

Can I have a nap between tests?

It is very important that you do not nap in between the MSLT nap tests, or it will affect the results.

Can I have caffeine?

No caffeine is allowed (coffee, colas, chocolates, etc.) all day.

Can I smoke?

Yes. The only time you cannot smoke is 30 minutes before each nap. You will need to go outside the building to smoke.

Will I be able to leave the lab?

You need to be monitored by a technologist all day to see that you are not falling asleep between naps. You can move around your room and the entire suite and go outside for short periods.

Will I be able to exercise?

Yes, as space allows. The only time you will not be able to exercise is 15 minutes before each nap.

How many naps will there be?

Your testing will be over as late as 6:30 p.m., but could be cut short at any time during the day.

After the MSLT

What happens after the sleep study?

A large amount of information is collected during your sleep study and MSLT. A sleep specialist will analyze this information and a formal report with recommendations will be sent to your doctor. The sleep technologists cannot provide you with any information about your testing results.

When will my doctor received my results?

It usually takes up to two weeks for your doctor to receive your formal report. Please schedule a follow-up visit with your physician after that time to discuss the findings and recommendations for treatment. If you have seen one of our specialists, we will contact you as soon as possible to discuss treatment options.