Multi-Sleep Latency Test (MSLT) (download sleep diary)

Multi-Sleep Latency Test (MSLT)

What is an MSLT examination?

An MSLT is a series of recordings that chart your brain wave patterns, eye movements, heartbeat and muscle movement.   They are used to help the doctor to diagnose some types of sleep disorder.

These tests are very time consuming so it is very important that you confirm your attendance.  You will be in the department from 08:45 until approximately 16:30.  The results will be sent to the referring GP/clinician and are usually available within seven days.


How is the test performed?

The test is painless.  Leads are attached to your head, chin, shoulders, and  leg.  You will then be asked to lie down and try to sleep.  Whilst you try to sleep your brain activity is monitored on an EEG (electro-encephalogram) recorder.  After between 20 and 35 minutes you will be asked to get up out of bed and stay awake until the next recording.   This process is repeated 4-5 times during the day. 

Between recordings you will be able to read, listen to music, watch a DVD or do some work.  Please feel free to bring your own laptop, DVDs or some paperwork/schoolwork if you wish.  It is important to stay awake between recordings.


How do I prepare for the test?

One of the Physiologist’s from the department will contact you to discuss the day with you and what to expect, where you will be welcomed to ask any questions.

A sleep diary will be sent to you, it is very important that you complete this for two weeks prior to the test and ensure you bring it with you on the day.

It is essential that you have had at LEAST six hours sleep the night before and please do not get up before 06:30hrs on the day of the test.

Please ensure your hair is clean and free from hairspray and oil and wear loose fitting, comfortable clothing.

You must not drink any products containing caffeine, e.g. coffee, tea, coke or stimulant drinks on the day of the test, and you must refrain from taking recreational drugs for one week prior to the test.

A sandwich lunch will be provided but please feel free to bring your own lunch, we have a fridge available to store this in.                                                                                                                                  


Actiwatch Wearer Guide

What is an Actiwatch?

The Actiwatch is a medical grade device that measures activity and light.  It is similar to a watch and is worn on your wrist.  Please start to wear the Actiwatch as soon as you receive it or on the day you have been instructed to start using it.  Normally the Actiwatch is used for either 7 or 14 days and you must wear this at all times.

What will it tell about me?

The Actiwatch provides information about your general activity, sleep schedule, naps, awake episodes as well as information about your sleep quantity and quality. 

Where and how do I wear it?

Wear the Actiwatch snugly and securely on either wrist.

Is Actiwatch water resistant?

Yes.  Wear it while you shower or bathe for up to 30 minutes. 


Discontinue use if your skin becomes red or inflamed. 

If the device becomes damaged discontinue use and contact the Neurophysiology Department at Calderdale Royal Hospital. 

Do not attempt to take the device apart. 

If you have any questions or problems whilst wearing the Actiwatch, please contact the Neurophysiology department.