Multiple Sleep Latency Test (MSLT)

Multiple Sleep Latency Test (MSLT) is a type of sleep study. It is always performed the day after a polysomnogram (PSG), and is used to identify problems with daytime sleepiness and narcolepsy. The reason it is done after a PSG is to ensure that there were no disruptions during sleep the night before that would cause daytime sleepiness.

The MSLT measures how long it takes a person to fall asleep at various times throughout the day. It involves a series of four or five 15 – 20 minute naps, taken at two hour intervals. The entire Multiple Sleep Latency Test takes about eight hours.

What Happens During a MSLT

A Multiple Sleep Latency Test is painless. Small electrodes will be glued to your scalp and other areas of your body and airflow devices will be taped to your nose and mouth.

You will take your naps in a quiet, dark room and will be observed by a sleep technologist. The electrodes, sensors and airflow devices will record and monitor your eye movements, brain waves, breathing and muscle tone changes. Your naps may also be videotaped for further analysis. You will be awakened after each nap and be able to leave the area and move freely around until the next testing period.

You may be asked to bring a friend or family member who can help you stay awake in between naps. The sleep center may also provide you with breakfast and lunch and you may be asked to complete a post-test questionnaire.

After your final test, you will be allowed to leave and the results of your Multiple Sleep Latency Test will be analyzed and discussed with you at a later appointment.

Disclaimer: These statements and products are not intended to diagnose, treat and cure or prevent disease. Always consult your physician regarding any sleeping disorders.