Which of the following are true about perceptual constancy?
A. It applies to perception of size and colour only.
B. Many visual illusions may be explained by the various constancies.
C. Constancies occur in all sensory modalities.
D. It keeps the appearance of objects the same in spite of large variations in the initial representation of the stimuli received by the sense organs that are engendered by various environmental factors.

Correct option is B

Perceptual constancy refers to the ability of the brain to perceive objects as unchanging despite variations in their appearance due to different environmental conditions, such as changes in lighting, distance, and angle.

Statement B is correct because many visual illusions are a result of the brain maintaining perceptual constancies despite changes in sensory input.
Statement C is correct because perceptual constancies are observed across multiple sensory modalities, including vision, hearing, and touch.
Statement D is correct because perceptual constancy allows objects to appear the same even when external factors, such as lighting and perspective, change their sensory representation.

Thus, the correct answer is B, C, and D only.

Information Booster:
-Types of perceptual constancy include size constancy, shape constancy, brightness constancy, and color constancy.
-Size constancy allows objects to appear the same size despite changes in distance.
-Shape constancy ensures that an object retains its perceived shape regardless of the viewing angle.
-Brightness constancy helps maintain the perception of an object’s brightness despite changes in lighting.
-Visual illusions often arise when perceptual constancies conflict with raw sensory information.
-Perceptual constancies are crucial for object recognition and navigation in varying environments.