Electroencephalography (EEG)

• Electroencephalography (EEG) Introduction
• Risks
• EEG Preparation
• During the Procedure
• After the Procedure
• Next Steps
• When to Seek Medical Care
• Results
• Synonyms and Keywords
• References
• Authors and Editors

Electroencephalography (EEG) Introduction

The electroencephalogram (EEG) is a measure of brain waves. It is a readily available test that provides evidence of how the brain functions over time.

• The EEG is used in the evaluation of brain disorders. Most commonly it is used to show the type and location of the activity in the brain during a seizure. It also is used to evaluate people who are having problems associated with brain function. These problems might include confusion, coma, tumors, long-term difficulties with thinking or memory, or weakening of specific parts of the body (such as weakness associated with a stroke).



• An EEG is also used to determine brain death. It may be used to prove that someone on life-support equipment has no chance of recovery.



• Scientists first captured and recorded brain waves in dogs in 1912. By the 1950s the EEG was used commonly throughout the United States.