MULTIPLE SLEEP LATENCY TEST
The Multiple Sleep Latency Test (MSLT) is a sleep disorder diagnostic tool. It is used to measure the time it takes from the start of a daytime nap period to the first signs of sleep, called sleep latency. The test is based on the idea that the sleepier people are, the faster they will fall asleep.
It can be used to test for narcolepsy, to distinguish between physical tiredness and true excessive daytime sleepiness, or to see if breathing disorder treatments are working. Its main purpose is to serve as an objective measure of sleepiness.
The Multiple Sleep Latency Test measures brain waves (EEG), eye movements (EOG) and muscle activity from the chin to determine sleep latency and sleep stage during naps.
A multiple sleep latency test is given during the daytime. The MSLT test usually follows an all-night sleep study. The MSLT test consists of a series of 20-minute naps, during which the patient tries to fall asleep. The test is given every two hours throughout the day, with each nap lasting about 20 minutes. During each nap, sensors and electrodes record data on body functions (heartbeat, breathing, eye movement, etc.).
If you are scheduled for an MSLT test following your all-night sleep study, please bring something to read, work on or watch during the day to help keep you occupied between naps. In order for the testing to be accurate, patients must remain awake between naps. A TV and VCR are provided in each room. Please feel free to bring in your own videos to watch in-between naps. The MSLT testing is usually completed between 5:00 and 6:00 p.m. on the day following the all-night sleep study.