Magnetoencephalography (MEG)
What is MEG?
Your brain works by means of tiny electrical signals, which are often called “brain waves” or “brain activity”. A MEG system (MEG stands for Magnetoencephalography), can measure brain activity and the scans produce an “activity map” of your brain. MEG doesn’t hurt, and there are no known side effects. You won’t feel any differently afterwards, and you won’t need to change your activities or rest after your scan.
What sort of information does MEG provide?
People have MEG recordings for many different reasons. Sometimes their doctor sends them for a recording to help decide how to best treat them. Some people volunteer for a recording to help in research. MEG recordings can help answer questions such as:
- What activity is the brain producing and where in the brain does it come from? For example, MEG can be used to measure brain activity associated with relaxation, migraine, or epilepsy.
- Which part of the brain undertakes different tasks? For example, MEG can determine exactly which bit of your brain controls actions such as speaking or moving arms and legs.
- How does the brain work? MEG researchers are working to further understand how the brain functions, both normally and when something goes wrong.
What will happen during my MEG recording?
When you arrive, one of the MEG team will meet you, explain what will happen, and answer any questions you have.
Please arrive for your appointment with your hair down with no grease, oil or other hair products in your hair. Please do not have your hair in plaits, braids, cornrows, dreadlocks or with any additional permanent hair weaves or hair extensions, as the excess height may not allow your head to fit in the scanner. Also, some braids may have metal clips. If you wear metal braces please contact our Clinic Administrators on 0121 204 3882 in advance of your appointment.
Before your recording, you will be asked to remove any metal objects you are wearing as metal objects interfere with the MEG system. Metal objects include mobile phones, watches, coins, credit cards, jewellery, glasses, and clothes that contain metal (e.g. tops with zips, bras, and shoes). It is therefore a good idea to wear as little metal as possible when you come for your recording – a tracksuit or similar is ideal. Also, some make-up contains metal fragments so we ask that you do not wear any make-up.
You will then have 5 small sensors attached to your head (3 on your forehead and one behind each ear), which record where your head is in the scanner, and a special pen is traced around your head. This is so that an accurate computer picture of the shape of your head can be produced.
You will then be taken into the special room where the MEG system is – this room has been specially designed to reduce artefacts from the environment, so the small brain waves can be recorded by the system. In the MEG room, you will sit on a chair, which moves you up slightly so that the top of your head is in the MEG helmet.
Somebody will be with you all the time, and if you would like a friend or relative to sit with you, just ask one of the MEG team. The MEG system is very quiet, so you will be told when the recording starts, and to keep very still during the scan. You may be asked to perform a task while you are being scanned, such as tapping your fingers or looking at pictures.
How long will my MEG recording take?
Different types of recording take different amounts of time. As a rough guide, you can expect to be in the MEG unit for around 1-3 hours for a clinical recording, and between 1-2 hours for a research study.
What happens to my results?
After your recording, you may have other tests done, such as an MRI (this stands for Magnetic Resonance Imaging and gives a picture of the structure of your brain). You will be given details of these tests separately.
Your MEG recording takes a long time to analyse, so you won’t be given any results on the day (although you can ask to see your brain activity on the computer screen). If your MEG recording is for clinical reasons, the results of your recording will be sent to your doctor, who will contact you when they are ready. You will probably have other tests done, and your doctor will use the information from all the tests to help decide on the best way of treating you. If your MEG scan was for research (not arranged by your doctor), then there are no results, as your recording is simply used to help find out about how the brain works.
Do I need to do anything before my MEG recording?
Generally, you do not need to do anything before your scan: you can eat and drink normally and do everything you normally do. You should dress in comfortable clothes and avoid wearing any clothes that contain metal. If you are on medication, you should continue to take it as normal UNLESS your doctor has told you not to. If you have a mobile phone, you should turn it off when you arrive at the MEG unit, as it interferes with the MEG system.
Where is the MEG system?
The MEG system is in the Aston Brain Centre at Aston University in the centre of Birmingham. At the University you should go to the Aston Brain Centre and use the phone at the front door to tell the team of your arrival. You will then be directed to a waiting room. There are some free car parking spaces next to the Aston Brain Centre; please ask for a permit when you arrive as this needs to be displayed in your vehicle. If your doctor has arranged for an ambulance or taxi to collect you, and it does not arrive, please telephone us to let us know.
What is the difference between a clinical and a research recording?
Both clinical and research work is carried out at the MEG unit, and the procedures are very similar. Someone having a clinical recording is referred by their doctor, and the results are used to answer a specific question that will help their doctor make a diagnosis, or decide on the best course of treatment. Their results are sent to their doctor. Someone having a research recording has volunteered to take part in a research project that aims to find out more about how the brain works or to improve a clinical test. The researchers analyse the MEG recording, but there are no results. Only doctors can refer people to have a clinical recording, but anybody can volunteer for a research recording. Please tell one of the MEG team if you would like to know more about current research projects or would like to volunteer to take part in research.
Remember
- MEG doesn’t hurt and it isn’t harmful.
- The MEG team are very friendly – just ask if you want them to explain something to you or if you are unsure about anything.
- Try not to wear any metal, and if you have contact lenses, wear them instead of your glasses.
- If you require any further information please contact our Clinic Administrators on 0121 204 3882 or abc_admin@aston.ac.uk