Explain the phenomenon of perceptual constancy with a suitable example.

Question

What will be an ideal response?

Answer 1

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The answer should include the following information:

Perceptual constancy is a phenomenon in which physical objects are perceived as unvarying and consistent despite changes in their appearance or in the physical environment. In some cases, though, our application of perceptual constancy can mislead us. One good example of this involves the rising moon. When the moon first appears at night, close to the horizon, it seems to be huge-much larger than when it is high in the sky later in the evening. One may think that the apparent change in the size of the moon is caused by the moon's being physically closer to the earth when it first appears. However, this is not the case at all. The actual image of the moon on the retina is the same, whether it is low or high in the sky. Perceptual constancy is not the only explanation for the moon illusion, and it remains a puzzle to psychologists. Instead, the moon appears to be larger when it is close to the horizon primarily because of the phenomenon of perceptual constancy. When the moon is near the horizon, the perceptual cues of intervening terrain and objects such as trees on the horizon produce a misleading sense of distance. The phenomenon of perceptual constancy leads us to take that assumed distance into account when we view the moon, and it leads us to misperceive the moon as relatively large.