Electroencephalograms (EEGs) are a diagnostic method used to measure electrical brain waves in order to detect or localise pathological changes in the brain's electrical activity. EEGs are most commonly used in cases of epilepsy or when there is a propensity for seizures. Changes in the EEG recording may indicate inflammation in the brain. They may also indicate metabolic or local disturbances in the brain such as a stroke or a tumour.

The brain's electrical impulses ('brain waves') are recorded by means of electrode plates attached to the head. EEGs can be carried out by neurologists, neuropaediatricians (paediatric neurology), psychiatrists and physiotherapists (provided the latter have additional certification).