Brenner D, Williamson S J, Kaufman L
Science. 1975 Oct 31;190(4213):480-2. doi: 10.1126/science.170683.
Magnetic field variations from the human brain produced by visual stimulation have been observed in a normal laboratory setting with a superconducting quantum interference device and no magnetic shielding of the subject. Previously unknown temporal and spatial features of the field near the scalp are reported.