Electroencephalography
EEG (electroencephalography) is the technique that records brain waves by detecting electrical signals from the scalp, revealing activity patterns like frontal theta spikes during hard thinking.
Electroencephalography (EEG) is a non-invasive method that records the brain's spontaneous electrical activity using sensors placed on the scalp. It detects voltage fluctuations resulting from ionic current within neurons, producing waveforms like alpha, beta, and theta bands to assess brain function, sleep states, and neurological conditions. This technique provides high temporal resolution, making it ideal for studying real-time cognitive processes and diagnosing disorders like epilepsy.
What this means in real life
A child who has unexplained fainting spells might undergo this test, where sticky sensors are placed on their head to record whether abnormal electrical patterns in the brain are causing the episodes.
What it isn’t
This is not brain imaging like an MRI or CT scan—it doesn't show the brain's structure or location of activity, only the electrical signals themselves. It also cannot read thoughts or measure intelligence.
Commonly misused online
Social media often claims this test can detect 'mind control' or 'psychic abilities,' when it simply measures normal electrical brain activity used for medical diagnosis.
Based on 1 reference source, including primary sources. Last verified July 12, 2026.