Electroencephalogram (EEG)

Electroencephalogram (EEG). The electroencephalogram (EEG) is a recording of the electrical activity of the brain from the scalp. The recorded waveforms reflect the cortical electrical activity. This electric activity is very low in amplitude (in microvolts) compared to the ambient noise which is in volts. The EEG utilizes differential amplification to amplify the waveform of interest and filters out other ambient noise.