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An electroencephalogram (EEG) records and measures your brain’s electrical activity, including brain wave patterns and any unusual changes. Brain cells communicate with each other by sending electrical signals, even when you’re asleep. On an EEG, this activity looks like wavy lines.
For most types of EEG, our technicians attach electrodes (small, metal sensors) to your scalp using washable glue. Or you may wear a cap with embedded electrodes. These EEGs usually take about one hour to several hours. In some cases, our neurosurgeons perform surgery to place electrodes in or on the brain to record electrical activity for a longer period of time.
The electrodes sense the electrical impulses as they travel between brain cells. The electrodes send information about the impulses through wires connected to the EEG equipment. The equipment records the information as lines that show your brain wave patterns.
The brain produces specific wave patterns when you’re asleep or awake. Changes in these patterns can occur with seizures, sleep disorders, brain injuries, and other brain conditions.