Electroencephalogram

Alternative names

Electroencephalography

Definition

Diagnostic test belonging to the field of Neurophysiology that consists of recording brain electrical activity through the use of electrodes (coin-shaped) that collect the different brain electrical impulses, an amplifier, a recording device that transforms said impulses into a brain wave recording and a computer for interpretation and further study.

Brain electrical activity is that which arises from the different electrical impulses generated by neurons (cells of the central nervous system) to communicate with each other.

How is the study done?

The study is carried out in the Neurophysiology Unit of the medical center or hospital by specialized personnel.

The patient remains lying down or sitting on a stretcher during the study. The examiner will place a certain number of adhesive electrodes on specific areas of the scalp and will proceed to record the electrical activity of the brain at rest (immobile and with the eyes closed) and under certain stimuli such as opening and closing the eyes, looking at a light. bright or breathe deeply.

The study usually lasts 15-20 minutes.

In some cases, a 24-hour record may be requested, in other cases a night record, and in others a study after sleep deprivation.

Preparation for the study

Electroencephalography does not require prior preparation by the patient.

Taking stimulant substances such as caffeine should be avoided 24 hours prior to the study.

Some drugs can modify the result of the study so the patient should consult with his doctor if he performs any type of treatment before the study is carried out.

The application of creams or lotions to the scalp on the day of the study should be avoided.

Hair washing is recommended the night before the study.

What does the study feel like?

The EEG study is painless for the patient.

Study risks

There are no risks to the patient.

Study contraindications

The patient should consult with his doctor before carrying out the study in case of:

• Taking medication
• Seizures
• Epilepsy

Reasons why the study is done

Electroencephalography is a widely known and widely used test in the field of Neurophysiology and Neurology; It has multiple applications since it provides objective information on the state of brain electrical activity.

It allows detecting abnormalities in brain electrical activity typical of alterations that affect the cerebral nervous system such as intoxications, drug use, inflammatory, infectious, vascular, tumor or degenerative diseases, among others.

Study widely used for the diagnosis of sleep problems or epilepsy foci.