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What's A Maintenance of Wakefulness Test (MWT)?

The MWT measures how alert you are during the day and if you're able to stay awake for a period of time in a quiet, relaxing environment. It's also used to see if someone with a sleep disorder is responding well to treatment. This test is given throughout the course of a day.  

man with one eye open in bed, humorous

When you arrive for your sleep study, a Registered Polysomnographic Technologist or  Respiratory Therapist will be at the site to greet you and show you to your room. After you make yourself comfortable, your technologist will take a brief history, explain the testing process, and answer any questions you may have. The next step is to apply the sensors, which is painless and takes about 40 minutes.

What To Expect

Getting Ready

First, the technologist will use stickers to affix leads on your chest and abdomen. 

Next, your head will be marked and measured with a paper ruler and a grease pencil. This is done because each electrode needs to be placed in a precise location in order to accurately measure your brain waves. Once this is complete, a skin prep jelly will be applied to clean your scalp for the electrodes. This jelly removes any excess oils or skin cells in order to obtain a clear reading of your brain waves.  

Lastly, the electrodes are placed on the surface of your scalp with a small amount of paste.  The prep, paste, and tape are hypoallergenic.


The tests consist of four trials that are 40 minutes each. The first test starts approximately 45 minutes after you arrive.

Once you are fitted with the sensors, you are free to stay in your room where you can relax, catch up on phone calls, enjoy Smart/Cable/Vios TV and Wi-Fi, or read in between testing periods. 

You may bring your own food/snacks.  Lunch is provided; please notify us of any special dietary needs in the morning when you arrive.

Your technologist will monitor your testing remotely throughout the study and will be available to answer questions and ensure you’re comfortable. 

All Done, Now What?

Once your study is complete, the technologist will remove the electrodes and leads. Any remaining paste or marks can be easily washed out using warm water and shampoo.

At your follow-up appointment, you'll receive your test results and discuss them with your provider.

Preparing For Your Sleep Test

Sleep Insights offers a relaxing environment with private, hotel-like rooms and at certain locations, a shower may be available.

  • Set Time Aside

    This test takes approximately 9 hours. Plan to be at our sleep center for the entire day. This is not an overnight test.

  • Wash and Dry Your Hair

    Wash and dry your hair thoroughly but do not use conditioners or other hair products.

  • Hair Accessories

    Remove any hair weaves or extensions. We cannot do testing if you have either of these.

  • What Should I Wear?

    Wear comfortable, loose-fitting clothing to relax in throughout the duration of your test.

  • Medications

    Bring – and take – all of your normally scheduled medications unless otherwise directed by your doctor or the staff at Sleep Insights.

  • Special Requirements and Guests

    Guests are not allowed to stay overnight with patients other than for specific medical reasons (e.g. parent with a child, caregiver for patient with special needs). Arrangements for caretakers must be made with advanced notice and with prior permission from their provider. Anyone accompanying a patient to their sleep test who isn’t an approved caretaker must remain in the waiting room.

  • Smoking

    Smoking, vaping and the use of alcohol are not permitted in the building or on the premises at any time.

  • No-Show

    Cancellations must be made by at least 12 noon the day before your study, or if your study is on a Saturday or Sunday, by noon on the Friday before. 

    Failure to show up for your scheduled test will result in a $100.00 no-show charge.