title: The Pulfrich stereo-illusion as an index of optic nerve dysfunction.
abstract: A simple test based on the Pulfrich phenomenon may provide an indication of optic nerve dysfunction. When a small object swinging pendulum fashion is viewed binocularly by a person with one eye covered by a neutral density filter, the object appears to swing in an elliptical path. The patient with optic nerve dysfunction may see it this way without use of a filter. The Pulfrich theory is explained, clinical applications are discussed, and instructions for constructing a Pulfrich apparatus are given.
mesh_terms: D005071:Evoked Potentials; D006801:Humans; D007088:Illusions; D009103:Multiple Sclerosis / Q000150:complications; D009900:Optic Nerve / Q000503:physiopathology; D009902:Optic Neuritis / Q000175:diagnosis* / Q000503:physiopathology; D009903:Optical Illusions; D009905:Optical Rotatory Dispersion / Q000295:instrumentation*; D009435:Synaptic Transmission