Electroencephalograms, or EEGs, are tests used to visualize brain activity and diagnose seizures in patients with epilepsy. The tests can last 45 minutes up to several days. During extended EEG ...

Hans Berger recorded the first human EEG in 1924. EEG records electrical activity via 16–25 scalp electrodes. Focal “slowing” in brain waves can indicate tumors or lesions. Patients must avoid ...