Ludwig Von Drake (Paul Frees)

Because EEG potentials are of such low voltage, artifacts can be problem. Artifacts can be broken down into three categories: equipment deficiencies, environmental interference sources, and patient sources. Patient artifacts are low frequency non-periodic events. Often, the EEG technician can observe the patient action, such as a movement, that is the cause of the artifact. Environmental or equipment generated interference usually show higher frequency activity (50 Hz or greater). Equipment issues include electrode/leadwire defects, poor common mode rejection, or internal failure of circuits or connections. Environmental interference can be caused by poor grounding and electromagnetic radiation sources showing as AC periodic interference.