Why do illusions occur

Perceptions of human beings are not always veridical. Sometimes he fails to interprete the sensory information correctly. This results in a mismatch between the physical stimuli and its perception. These misperceptions resulting from misinterpretation of information received by our sensory organs are generally termed as illusions. Illusion result from an external stimulus situation and generate the same kind of experience in each individual. Although illusions can be experienced by the stimulation of any of our senses, psychologists have studied them more commonly in the visual than in other senses modalities.

Illusions occur because of a result of a mismatch between the physical stimuli and its perception by the individual. The mismatch is caused by incorrect interpretation of information received by sensory organs. Illusions are called primitive organisations as they are generated by an external stimulus situation that generates the same kind of experience in all the individuals. Some illusions are universal in nature as they are found in all individuals. They are also known as universal illusions or permanent illusions because they do not change with experience and practice. Contrary to this, illusions that vary in different individuals are known as personal illusions.