EEG is short for Electro-Encephalo-Graph. The EEG records the ever changing, but tiny electrical signals coming from the brain, which are picked up by electrodes places on the scalp. These electrodes do not send any electricity, they only receive electrical signals naturally generated by the brain. An EEG can be performed if you are experiencing blackouts or spells of various nature, seizures, headaches, depression, a sleep disorder, dizziness, problems with memory, or weakness of arms and legs. This test is used to help evaluate the health of the brain, to diagnose nervous system disorders and evaluates the electrical patterns of your brain to determine if there is abnormal electrical activity. An EEG may be performed while you are awake or while you are asleep. About 20 electrodes are placed over the scalp, next to the eyes and under the chin. These electrodes are connected with wires to the EEG machine. The original signals from the brain are very small (measured in millionths of a volt), and the EEG machine increases the size of these electrical signals, so that they can be recorded on paper, computer or tape. This produces a permanent record which can be interpreted by the EEG Consultant.
There are several ways of making an EEG recording:
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A standard EEG. The test takes place in the hospital, while the patient is sitting or lying down. The EEG recording takes about 1 hour to 1½ |
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A sleep EEG. The test takes place during sleep |
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A portable EEG. The patient wears the EEG recorder on a waistbelt for one or more days. Recording their brain activity while they are awake and asleep. |
More information about EEG's:
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