An EEG (Electroencephalogram) is one of the most important and widely used diagnostic tests in neurology, helping doctors evaluate the electrical activity of the brain quickly and accurately. Unlike imaging tests such as X-rays or CT scans that show structural details, EEG focuses on brain function by recording the tiny electrical signals produced by brain cells. It uses small metal discs called electrodes, which are placed on the scalp, to detect and record these signals without causing pain or discomfort. The test provides valuable information about brain activity patterns that cannot be seen from the outside.

During an EEG examination, the patient is asked to sit or lie comfortably while multiple electrodes are attached to the scalp using a special gel or paste. These electrodes are connected to a machine that records brain wave activity and displays it as wave-like patterns on a computer screen. The procedure is completely painless and does not send electricity into the brain; it only records natural electrical activity. The test usually takes about 20 to 60 minutes, although longer recordings may be required in certain cases. In some situations, the patient may be asked to breathe deeply, look at flashing lights, or even sleep to help detect abnormal brain activity.

EEG is commonly used to diagnose and monitor conditions such as epilepsy and seizure disorders, unexplained fainting spells, sleep disorders, brain infections, head injuries, encephalopathy, and coma. It also plays a crucial role in evaluating abnormal brain function, monitoring patients in intensive care units, and assessing brain activity before and after neurological treatments. In emergency settings, EEG can help identify ongoing seizures or assess brain function in critically ill patients.