Optical Illusion: (An Ice Cream Cone Under a Strobe Light at 55 Hz.)
An optical illusion is characterized by visually perceived images that differ from objective reality. The information gathered by the eye is processed in the brain to give a perception that does not tally with a physical measurement of the stimulus source.
Physiological illusions, such as the afterimages following bright lights, or adapting stimuli of excessively longer alternating patterns, are presumed to be the effects on the eyes or brain of excessive stimulation or interaction with contextual or competing stimuli of a specific type—brightness, colour, position, tile, size, movement, speed, etc. That intense or repetitive activity causes a physiological imbalance that alters perception.