ambiguous figure. This perceptualinstabilityof ambiguous figures is one of
their most important characteristics.
Thevase/facesandtheNeckercubeareexamplesofambiguityintheper-
ceptual organization stage. You have two different perceptions of the same
objects in the environment. The vase/faces can be seen as either a central white
object on a black background or as two black objects with a white area between
them. The Necker cube can be seen as a three-dimensional hollow cube either
below you and angled to your left or above you and angled toward your right.
With both vase and cube, the ambiguous alternatives are different physical
arrangements of objects in three-dimensional space, both resulting from the
same stimulus image.
The duck/rabbit figure is an example of ambiguity in the recognition stage. It
is perceived as the same physical shape in both interpretations. The ambiguity
Figure 7.4
Sensation, perceptual organizing, and identification/recognition stages. The diagram outlines the
processes that give rise to the transformation of incoming information at the stages of sensation,
perceptual organization, and identification/recognition. Bottom-up processing occurs when the
perceptual representation is derived from the information available in the sensory input. Top-down
processing occurs when the perceptual representation is affected by an individual’s prior knowl-
edge, motivations, expectations, and other aspects of higher mental functioning.
140 Philip G. Zimbardo and Richard J. Gerrig