EEG :
An EEG or electroencephalogram is a test that records the electrical activity of the brain. Electrodes which are small devices that are used to measure electrical impulses. They are placed on the scalp and then they detect the impulses produced by the brain. This procedure is very sensitive for diagnosing some disorders related to the functioning of the brain like epilepsy, seizures, sleep disorders, brain injuries, and certain types of brain infections. The procedure is non-invasive and usually takes between 20 to 40 minutes. It does not hurt but the head can feel a little uncomfortable. An EEG can reveal abnormalities in brain wave patterns that might help doctors determine what causes such symptoms as unexplained seizures, confusion, or memory problems. Many doctors use EEGs in combination with other test results and medical history to make a diagnosis. This can be carried out in hospitals an outpatient basis and recording of brain activity may need to occur over an extended period particularly when the diagnosis of seizure disorders needs to be determined.