electrical activity of the brain

spontaneous or evoked changes in electrical brain potentials. Spontaneous electrical activity of the brain was discovered by British physiologist Richard Caton (1842–1926) and others around 1875 but was not explored in detail until the development of sophisticated electronic recording devices in the 1930s. The oscillations may vary in frequency from 1 to more than 50 Hz, and from 50 to 200 mV in amplitude, as recorded by electrodes attached to the scalp. See also brain waves.

Browse dictionary by letter

a b c d e f g h i j k l m n o p q r s t u v w x y z

Psychology term of the day

July 27th 2024

horizontal–vertical illusion

the misperception that vertical lines are longer than horizontal lines when both are actually the same length. The vertical element of an upper case letter T, for example, looks longer than the cross bar, even when the lengths are identical. See also foreshortening; Helmholtz square illusion.