



A descriptive term referring to the measurement and recording of brain waves through electrodes placed at the cerebral cortex.
1. A recording of the electrical impulses from the brain by electrodes placed directly on the cerebral cortex.
2. The process of recording the electric activity of the brain by electrodes placed directly on the cerebral cortex, providing a much higher voltage, greater accuracy, and more exact localization than electroencephalography.
A recording of electric currents or changes in electric potential from the urinary bladder.
electrodynograph, EDG
An electronic device used to measure pressures exerted in biologic activity; such as, those exerted by the human foot in walking, running, jogging, or climbing stairs.
electroencephalograph, EEG
1. An instrument that measures and records brain wave or the electrical potentials on the scalp and generates a record of the electrical activity of the brain.
2. An apparatus for receiving and recording the electric potential produced by the brain cells.

It consists of a vacuum tube amplifier that magnifies the electrical currents received through electrodes placed on the scalp and electromagnetically records the patterns on a graphic chart.

3. An appliance that is used to amplify and to record the electrical activity of the brain, either through the intact skull and scalp, or directly from the exposed cerebral cortex (electrocorticography).

It is made up of a number of channels, each of which consists of an amplifying and recording instrument that records the electrical events beneath and between a pair of recording electrodes.

1. A reference to an electroencephalograph, or electroencephalography, in which the electrical activity of the brain is measured for the diagnosis and treatment of brain disorders.
2. Pertaining to an instrument that records the electric activity of the brain.
electroencephalographic lead
A pair of terminals that measures the potential differences resulting from cerebral activities between two points on the skull.
electroencephalographic technologist
A person trained in the management of an electroencephalographic laboratory.

The technologist may supervise electroencephalographic technicians, who are generally responsible for the operation and maintenance of the equipment.

electroencephalography, EEG
1. The recording of the electric currents developed in the brain, by means of electrodes applied to the scalp, to the surface of the brain (intracranial) or placed within the substance of the brain (depth).
2. A method of graphically recording the electric activities of the brain, particularly the cerebral cortex, with electrodes attached to the scalp.

This process is used in the diagnosis of epilepsy, trauma, tumors, and degenerations of the brain; as well as, in the study of the effects of drugs on the central nervous system and certain psychological and physiological functions.

3. Amplification, recording, and analysis of the electrical activity of the brain. The record that is produced is called an electroencephalogram.

Electrodes are placed on the scalp in various locations and the difference between the electric potential of two sites is recorded. The difference between one pair or among many pairs at a time can be determined.

The use of this diagnostic technique has proven to be very helpful in studying epilepsy and convulsive disorders and in localizing lesions in the cerebrum.

4. The process of recording brain wave activity by attaching electrodes to various areas of the patient's head with collodion (highly flammable, colorless or yellowish syrupy solution of pyroxylin, ether, and alcohol, used as an adhesive).

During the procedure, the patient must remain quiet, with eyes closed, and not talk or move.

In certain cases prescribed activities; especially, hyperventilation, may be requested by the technician.


During neurosurgery, the electrodes can be applied directly to the surface of the brain (intracranial electroencephalography) or placed within the brain tissue (depth electroencephalography) in order to detect any lesions or tumors that might exist.

1. An electrical device for engraving a design on a metal plate which is used for printing patterns on fabrics or wallpaper.
2. An apparatus used to transmit pictures by electrical means; for example, by fax.
3. A graphic representation created by the movement of an electric current on sensitized paper or an electrically controlled writing instrument used in telecommunications.
A reference to an electrical device for engraving a design on a metal plate which is used for printing patterns on fabrics or wallpaper.
electrographic technician
A health care provider with special training and experience to assist the physician in recording and analyzing muscle action potentials with the use of various electronic devices.
1. The process of copying an engraving on an electro-copper plate.
2. The branch of electrostatography in which electrostatic images are formed on an insulating medium without the aid of eledgromagnetic radiation.

It includes xeroprinting, where the charged image is permanent, as required for repetitive printing and electrographic recording, in which the charged image is formed by electric procedures.

3. Any technique involving the recording of electrical potentials in resting bodily tissues or organs, and of changes in these potentials during physiological or pathological activity.
