What are illusions in a psychological context?

In a psychological context, illusions are best described as false perceptions that occur in the presence of real external stimuli. Unlike hallucinations, which involve perceiving something that isn't there, illusions involve misinterpretations of actual sensory information. For example, seeing a stick in water and perceiving it as bent is an illusion because the visual distortion is influenced by the actual physical properties of light and water.

Illusions do not inherently imply an altered mental status; instead, they arise from the way the brain processes sensory information. The presence of a genuine stimulus is what distinguishes illusions from other perceptual disturbances such as hallucinations. Therefore, the understanding that illusions are related to the reality of stimuli, yet still lead to a misleading perception, reinforces the knowledge of that psychological phenomenon. Thus, option A accurately captures the essence of illusions within the realm of psychology.