Your brain works through a series of tiny electrical signals, which are often called "brain waves" or "brain activity". MEG, or MagnetoEncephaloGraphy is non invasive and uses a machine which sits outside the head to measure brain activity and produce an 'activity map' of this activity.
The procedure is entirely painless and has 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.
People have MEG scans for many different reasons. They can help answer questions such as:
In some cases, yes, as MEG and MRI tell you different things about the brain. An MRI scan (Magnetic Resonance Image) only gives you information about the structure of the brain and nothing about its functioning. A MEG scan, on the other hand, can be used to tell you the locations in the brain that were active during a certain task and also at what point in time they were active.
Generally, you do not need to do anything before your scan - you can eat, drink and go about your daily routine as normal.
On the day - you should dress in comfortable clothes. Before your scan you will be asked to remove any metal objects you are wearing - this is because metal objects interfere with the MEG machine. These would include watches, coins, credit cards, jewelry, glasses and clothes that contain metal (e.g. tops with zips, bras). It is therefore a good idea to avoid wearing any clothes that contain metal and if you have contact lenses wear them instead of your glasses. 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 also interferes with the MEG scanner.
Your brain waves are directly displayed on a computer screen whilst you're in the MEG scanner. You can ask the technician if you can view them when the recording has finished. However, an in-depth analysis of your brain waves and the procedures that we use to find out which areas in the brain were active is very time-consuming, so you won’t be given any results on the day. For patients, the results will be sent to their doctor, who will contact them when they are ready. If your MEG scan was for research only, then the scan will be used as part of a research project and the results will be published in a scientific journal.