Maintenance of Wakefulness Test (MWT)

The maintenance of wakefulness test (MWT) measures a patient's alertness during the day and whether or not he or she is able to stay awake in a calm, quiet environment for a specific period of time. The MWT can also be used to determine how patients with sleep disorders are responding to treatments.

The MWT consists of four sleep trials with breaks in between lasting for two hours. The test begins in the morning and will continue throughout the day. Sensors are placed on a patient's head, face and chin, and he or she will be asked to sit quietly in the bed.

The goal is for the patient to stay awake as long as he or she can. The sensors will monitor changes in breathing patterns and heartbeat, and will alert technicians when the patient falls asleep. He or she will be allowed to sleep for 90 seconds before being awakened. Each cycle lasts approximately 40 minutes.