EEG is the current generated by the brain itself, and traced by EEG instrument graphics, no damage to the brain. All living cells produce electrostatic constantly, known as "bio electricity". The current is too small to detect with the general method, but the biopotential amplifier is thousands of times, you can figure out the painting line. If the painting is the current map of the brain is called eeg. Similarly, there are ECG, EMG, Electrogastrogram etc.. Although the line drawing is crooked, but has its regularity and scientific and professional personnel to understand its meaning, and accordingly make judgment of normal or abnormal.

In recent years, there is a "Ba", it is the EEG machine and electronic computer connected to the special equipment. Cerebral biocurrent magnifying EEG with disk recording after the input computer, processed into different shades of color graphics. Therefore, it is no longer see the curve "topographic map". EEG and EEG is reflected in brain tissue of bioelectricity, like ECG, will not cause any damage to the human body.