title: Upper-velocity threshold for detection of movement.
abstract: The maximum velocity with which an object can move and be seen to be moving was measured as a function of its luminance. Object movements greater than 1000 degrees /sec can readily be detected as movement. Saccadic eye movements should therefore produce sensations of visual movement. The absence of such sensations indicates that correct evaluation of the resulting visual input requires some other mechanism.
authors.forename: J R
authors.initials: JR
authors.lastname: Johnstone
authors.forename: L A
authors.initials: LA
authors.lastname: Riggs