University of Iowa Department of Neurology
Peer Review Status: Internally Peer Reviewed
Creation Date: Unknown
Last Revision Date: June 2000
An MSLT test is a series of recordings to monitor a person's sleep patterns. Electrodes are placed on your face and head to record eye movement, muscle tone, and brain waves.
What is it?
- a series of recordings to monitor your sleep patterns
- eye movements, brain electrical activity, and muscle tone changes are recorded during 15 to 20 minute naps, spaced about 2 hours apart
How long does it take?
- about 8 hours
- from 8:00 a.m. to 4:00 p.m.
Why is an MSLT performed?
- to evaluate excessive daytime sleepiness and narcolepsy (sudden and uncontrollable onsets of sleep)
Does it hurt?
- no. During the test you will not experience any pain or discomfort
Where is it conducted
- Neurology Sleep Disorder Center
- at the Neurology Clinic, 2nd floor of Carver Pavilion
How many MSLTs are conducted each year?
What should you do to prepare for the test?
- you must bring a family member or friend with you to help keep you awake between testing periods
- you may want to bring reading material or something to keep you occupied during the two-hour intervals between testing periods
- continue taking prescribed medicaitons unless your doctor gives other instructions. If you are taking stimulant drugs for narcolepsy, these should be discontinued under the direction of your physician approximately five to seven days before the MSLT.
- wash your hair before coming for the test. Do NOT use any sprays, oils, or dressings of any kind.
- eat normal meals
How is the MSLT performed?
- you will recline in a comfortable chair and asked to remain very still
- a technologist will glue "recording electrodes" on your scalp and face
- a special jelly is applied to each electrode; nothing goes into or under your skin
- each electrode is checked with a meter to ensure proper functioning
- you will be taken into a "sleeping" room, the lights turned off, and you will be asked to go to sleep for 15 to 20 minutes
- recordings are taken while you sleep
- don't worry if you cannot sleep during the test. The information gained will still be useful.
During the tests
After the test
- after each testing period, the technologist will awaken you. You are free to leave the area for the two hours between testing periods.
- there will be a total of five testing periods
- the electrodes are removed with acetone, which dissolves the glue and leaves your hair and skin intact
- you may return to your hospital room or home, unless given other instructions from the doctor
- you may wash your hair
- test results are available from your doctor in about a week