Electroencephalography (EEG)

What Is EEG ?

Our Brains are Constantly Working

Every thought, feeling, sensation, memory, motion, action and reaction happens because nerve cells in our brains produce tiny electrical signals. These signals are passed from nerve cell to nerve cell to transmit information. These electrical signals change when the brain is damaged from injury or illness.

Electroencephalography is the recording and study of these electrical signals. It is commonly referred to as EEG. Neurodiagnostic professionals use an electroencephalograph, a medical device that records the brain’s electrical signals, to create a picture of the electrical activity and health of the brain. The recording is known as an electroencephalogram.

Neurodiagnostic Technologists and Technicians use the modern medical equipment to monitor how well a person’s brain is functioning. They attach a series of metal electrodes to a patient’s scalp to detect the small electrical charges that are passed by the nerve cells.

The latest systems use sophisticated computer technology to amplify the electrical activity to create a detailed recording of the brain’s activity. The recording is shared with neurologists, physicians, and surgical teams to help them identify and treat patients for a variety of conditions including physical injuries, stroke, tumors, epilepsy, sleep disorders, and congenital and degenerative disorders and diseases.


The Inside Story

In 1875 an English physician, Richard Caton, discovered electrical signals in the brains of animals. He measured the signals through holes drilled into the skulls. The information was interesting but wasn’t very practical for human application.

Electroencephalography (EEG) was born fifty-four years later when German psychiatrist, Hans Berger, announced that he had developed a way to detect and record the electrical signals in the brain without opening the skull. Berger called his new device the electroencephalograph. This new machine worked by using metal electrodes attached to the scalp to record the electrical activity onto a strip of paper. The recording is known as an electroencephalogram. Berger suggested that the brain’s electrical activity changes based on the functions of the brain like sleep, lack of oxygen and epilepsy.

At the time the scientific community basically ignored Hans Berger’s conclusions. But other researchers kept experimenting. Five years later Edgar Douglas Adrian and B. C. H. Matthews verified that the electrical activity of the brain could be measured. Then, in 1936, William Gray Walter used EEG to detect and locate a brain tumor. This opened the doors to the new field of neurophysiology.

Today Neurodiagnostic Technologists are vital members of professional healthcare teams. They provide valuable medical information that help medical teams diagnose and treat many neurological conditions.