Electrical potentials have been recorded from the brain of five normal human subjects by means of needle electrodes inserted about half a centimeter through the scalp, one near the external occipital protuberance and another about three inches forward and an inch to the side from the median line. The high time-constant of the amplifier, which was about a second, made it possible to obtain an almost distortionless recording of the low frequency waves. The amplifier was connected to the oscillograph element. The oscillation of the light beam projected from the element was photographed on sensitized paper.
Proceedings of the Iowa Academy of Science
©1936 Iowa Academy of Science, Inc.
Bagchi, B. K.
"The Adaptation and Variability of Response of the Human Brain,"
Proceedings of the Iowa Academy of Science, 43(1), 335-336.
Available at: https://scholarworks.uni.edu/pias/vol43/iss1/127