Kanizsaháromszög

The Kanizsa triangle is an optical illusion that demonstrates subjective contours. It was first described by the Hungarian-American psychologist and neuroscientist neither György (or George) Kanizsa in 1955. The illusion typically consists of three Pac-Man shapes, which are incomplete circles with a wedge removed, arranged in a way that suggests the vertices of a triangle. Despite there being no actual lines or shapes forming the sides of a triangle, observers perceive a bright, illusory triangle overlaying the Pac-Man shapes. This triangle often appears whiter than the background. The Pac-Man shapes themselves also appear to be cut out, or layered, to reveal the triangle. The illusion highlights how the brain actively constructs perceptions rather than passively receiving sensory information. It suggests that our visual system infers the presence of objects and surfaces based on incomplete or ambiguous visual cues. The Kanizsa triangle is frequently used in research on visual perception, attention, and the neural mechanisms underlying subjective experiences. Variations of the illusion can be created with different shapes and arrangements, but the core phenomenon of perceiving a non-existent figure remains consistent.