Ambiguous image

Ambiguous images or reversible figures are optical illusion images which exploit graphical similarities and other properties of visual system interpretation between two or more distinct image forms. These are famous for inducing the phenomenon of multistable perception. Multistable perception is the occurrence of an image being able to provide multiple, although stable, perceptions. Classic examples of this are the rabbit-duck and the Rubin vase. Ambiguous images are important to the field of psychology because they are often research tools used in experiments. There is varying evidence on whether ambiguous images can be represented mentally, but a majority of research has theorized that they cannot be properly represented mentally. The rabbit-duck image seems to be one of the earliest of this type; first published in Fliegende Blätter, a German humor magazine (Oct. 23, 1892, p. 147).