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Perceptual Constancy

How an object affects our senses depends in part on external conditions, and these conditions are always changing. An object viewed from one angle presents a different shape to our eye than when viewed from another angle; similarly, as the distance from which we view an object changes, the object will appear larger or smaller. In spite of this, even as conditions change and we see objects differently, we still recognize that they remain the same. This is what is known as perceptual constancy. If not for perceptual constancy, we might have difficulty recognizing familiar objects if we viewed them in a new and different context.


Explain what is meant by “perceptual constancy”, using the examples provided by the professor.

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In the reading passage, perceptual constancy is defined as the way we look at the objects from different angles which make them to look different in their shapes, even though we perceive that they are the same objects. The professor gives two examples to illustrate this. First, he states that when we look at an ordinary round plate, we see it as a circle but when we look at it from a horizontal view, it seems oval. However, we know that it is the same plate. Secondly, the professor explains that the students in the front rows in a big class see him bigger than when they sit in the back rows. However, they perceive that the professor is the same person with the same size, without any thinking about it.