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Sensation and Perception
Sensation and Perception: Psych 115s
Puzzle #5: The Hollow Mask Illusion
Below, you see 2 views of a hollow mask. The left image corresponds to viewing the outside of the mask (e.g., nose pointing at you), while the right image corresponds to a 180 degree rotation of the mask, so that you are viewing the inside of the mask (e.g., nose pointing away from you, as if you were about to put the mask on).
However, both of these views actually produce the same perceptual experience-- that of viewing the outside of the mask, with the nose pointed toward you, the viewer.
Using models described in class, give a brief explanation to this phenomenon. Then, compare and contrast this illusion with the 'crater/mound' effect (see below) that we discussed in the 'Seeing in 3D' lecture.
