The Opto-Gyral Illusion and Its Relation to the Nystagmus of the Eyes

Perception of the Body in Space: Mechanisms

“…Thresholds for detecting motion in the presence of a light are one-half to one-tenth the size of those measured in the dark (31,68,74,91,136,159). When the subject is rotated in the dark and has a single light source fixed in front of him, that light source also appears to move relative to the observer.…”

Task-Control of Arousal and the Effects of Repeated Unidirectional Angular Acceleration on Human Vestibular Responses

“…definite sequence during vestibular stimulation. van Dishoeck, Spoor, and Nijhoff (1954) and Vogelsang (1961) have related the illusion to sensation rather than nystagmus. Brown and Guedry ( 1951) noted no decline in the duration of the oculogyral illusion ( OGI) as a result of a series of stimulations in total darkness, although a similar series with the target light present, and a third series with room illumination resulted in marked declines.…”

Treatment of vestibular disorders with weak asymmetric base-in prisms: An hypothesis with a focus on Ménière’s disease

“…[26,27] related the drift of the after-image to the opto-or oculogyral illusion (OGI), however without further explaining it. The OGI refers to a drift of either a true subject-fixed target, or an inherently subject-fixed after-image, in the same direction as an actual self-rotation in healthy subjects [14,16,17,18,28,34,60,99]. Interestingly, the OGI is present even at otherwise perceptually subthreshold physical angular motion.…”