They take medical histories and prepare patients for the tests. To run tests, electrodes are applied to the patient's head and face. For special procedures, electrodes may also be placed on the chest, arm, leg, or spinal column.
Technicians operate recording instruments and monitor the testing.
After the test, they calculate the results and show them to doctors. EEGs may be run while patients are awake, sleeping, and under anesthesia during surgery. While testing, technologists monitor vital neurologic, cardiac, and respiratory signs and if an emergency takes place, the technologist provides care until help arrives. They may also supervise workers, keep records, schedule appointments, maintain equipment, and order supplies. Electroneurodiagnostic technologists who specialize in basic EEGs are often called EEG technicians.