Multistable perception

Multistable perception (or bistable perception) is a

Classification

Perceptual

The transition from one precept (an undefined term) to its alternative (the defined term) is called a perceptual reversal (Paradigm shift). They are spontaneous and stochastic events that cannot be eliminated by intentional efforts, although some control over the alternation process is learnable. Reversal rates vary drastically between stimuli and observers. They are slower for people with bipolar disorder.^[4][5]

Cultural history

Human interest in these phenomena can be traced back to

Multistable perception was a common feature in the artwork of the Dutch lithographer M. C. Escher, who was strongly influenced by mathematical physicists such as Roger Penrose.^{[citation needed]}

Examples

Real-world phenomena

Photographs of craters, from either the moon or other planets including our own, can exhibit this phenomenon. Craters in stereo vision, such as our eyes, normally appear concave. However, in monocular presentations, such as photographs, the elimination of our depth perception causes multistable perception, which can cause the craters to look like plateaus rather than pits. For humans, the "default" interpretation comes from an assumption of top-left lighting, so that rotating the image by 180 degrees can cause the perception to suddenly switch.^[6][7] This phenomenon is called the concave/convex, or simply up/down, ambiguity, and it confuses computer vision as well.^[8]

In popular culture

In literature, the science fiction novel, Dhalgren, by Samuel R. Delany, contains circular text, multistable perception, and multiple entry points.^{[citation needed]}

Multistable perception arises with the theater segments of