What is EEG (Electroencephalography)?

Electroencephalography (EEG) is a medical procedure using the recording of electrical activity in the brain to diagnose various brain disorders such as epilepsy, dementia, and tumor. It is used to study the brain activity of people with neurologic disorders, such as seizures and coma, or to test for the brain death of an individual. It is noninvasive, requiring no injections, and is a relatively quick and easy procedure.

Preparation for an EEG

When preparing for an EEG, it’s best to avoid products containing caffeine and alcohol 12 hours before the test. Your doctor may advise you to stop taking medications that interfere with the test results. Have a good night’s rest before the test and avoid mental and physical activities that would excite or tire you. If indicated, patients may receive sedation prior to the test.

Procedure of an EEG

During an EEG, electrodes are placed on the surface of the scalp. The electrodes detect the electrical signals from the brain and transfer them to the EEG machine. A special paste is usually applied to the electrodes to allow them to stay in place. It is important to relax during the recording to ensure accurate results.

The machine records the different electrical signals from the brain and translates them into digital signals. The digital signals are stored in the form of a graph known as an electroencephalogram. The EEG might take up to two hours, but the actual recording time may be much shorter.

Types of EEG

There are different types of EEG tests. A standard EEG is used to check the electrical activity of the brain during a short resting period. This type is used to diagnose seizures, to localize the areas of abnormal brain activity, or to identify which parts of the brain are not working properly. Other types of EEG tests include a prolonged EEG, a sleep-deprived EEG, and an ambulatory EEG.

Risks of EEG

EEG is generally safe and no risks are associated with the use of electrodes. However, there is a possibility of infection due to the use of conductive gel, but this is rare. Some patients may experience a mild headache or minor irritation due to the removal of the paste at the end of the EEG.

Why is EEG Done?

EEG is used to detect abnormalities in the electrical activity of the brain. It is used to diagnose and monitor various neurological disorders, such as epilepsy, coma, brain death, brain tumors, encephalopathy, and mental retardation. It may also be used to assess the effects of certain medications on the brain. EEG is also used in surgical planning for epilepsy and other neurological disorders.

When is an EEG Done?

EEG is typically used to diagnose and monitor neurological disorders, such as epilepsy, coma, and brain death. It is recommended for individuals who have experienced a seizure, show signs of confusion, experience strange movements, or show changes in behavior. EEG can also be used to follow up on treatment for the above conditions or evaluate medication responses.