The Jastrow Illusion is an optical illusion discovered by American psychologist Joseph Jastrow in 1892. This illusion involves two curved and tapered blade-like shapes that are identical in size but appear to be different when placed next to each other.
The reason for this deceptive perception lies in how we compare the lengths of the two shapes. When comparing the two shapes, we unconsciously refer to the shorter inner edges of the shapes, causing us to perceive the lower shape as longer and hence larger. This is because the lower shape’s longer outer curve is directly adjacent to the upper shape’s shorter inner curve, creating the illusion that the lower shape is larger.
Another contributing factor is our brain’s tendency to interpret the shapes as 3D objects, which introduces additional depth cues and further distorts our perception of their sizes.
In essence, the Jastrow Illusion is a fascinating demonstration of how our brain interprets visual information and how this process can be influenced by the arrangement and comparison of visual elements. It serves as a reminder that our perception is not always a faithful reflection of reality but can be subject to misinterpretations and distortions.