What Is A Maintenance of Wakefulness Test (MWT)?

The maintenance of wakefulness test (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 given throughout the course of a day.  

The MWT is also used to see if someone with a sleep disorder is responding well to treatment.

man with one eye open in bed, humorous

When you arrive for your sleep study, a Registered Polysomnographic Technologist (RPSGT) or Registered  Respiratory Therapist (RRT) 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 prior to applying the sensors.  This procedure is completely painless and generally takes about 40 minutes to make sure everything is placed correctly.

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 on your head needs to be in a precise location.  Once this is complete, a prep solution will be applied to clean the scalp for the electrodes. 

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 are conducted throughout the day and 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 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?

When the study is done, the technologist will wake you and remove the wires and sensors.

At your follow-up appointment, you will receive your EEG 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.
If you have any questions please contact us, call our Rochester office (585) 385.6070 or your local site.

  • 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.

  • Acrylic or Applied Nails

    If you have acrylic nails or applied ("fake") nails an index fingernail needs to be removed for the oxygen reading. If you have gel nail polish, the polish from one of the index fingers will need to be removed. Regular nail polish is fine. The oximeter does not read through acrylic or applied nails, nor gel polish.

  • 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

    Notify us of any special needs prior to your arrival.  If you are supervising a child or older patient who is having a sleep test, we have rooms equipped with an additional bed.  Please let us know in advance if you need special accommodations.

    Guests are not permitted to stay in the room without prior permission.

  • 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 procedure will result in a $100.00 no-show charge.