The Pulfrich effect and its relationship to retinal illumination.
The Pulfrich stereo-illusion effect occurs in patients with monocular anterior visual system disease when viewing a pendulum. It also can be induced by placing a monocular neutral-density filter in a normal subject. We studied 10 normal subjects to determine if the Pulfrich effect could be induced by monocular illumination in addition to monocular neutral-density filtration. Eighteen of 20 eyes observed the Pulfrich effect with monocular illumination, but the rotation of the ellipse was opposite in direction to that of the neutral-density filter. Our data suggests that the Pulfrich effect results from intereye luminance disparity.
Vaphiades
M S
MS
Department of Ophthalmology, University of Arkansas for Medical Sciences, Little Rock 72205-7199, USA.
Eggenberger
E
E
D005260:Female; D006801:Humans; D008029:Lighting; D008297:Male; D009903:Optical Illusions; D012160:Retina / Q000528:radiation effects*; D015349:Vision, Monocular