Optical illusion - why it occurs?

Optical illusions often trick us and make us perceive the world from a completely different perspective - they are misleading and make things around us seem odd. What we see is a merely a picture ‘painted’ the brain, created on the basis of multiple ambiguous stimuli that come from our eyes. Although we are not always aware of them, we are susceptible to illusions on a daily basis

How does the optical illusion arise and why does it occur? The explanation is extremely simple. Illusion occurs when the brain misinterprets the image of the reality due to factors such as shadows, light, contrasts, colours, etc. Illusions usually appear when the stimulus reaching the brain is unclear, incomplete, or when data is missing or the elements are connected in an unusual way.

There are many types of optical illusions - there are illusions that deform shape, size, or length, are the illusions of brightness, and colour, there are also those caused by the physiology of our visual system. The latter are related to the existence of so-called blind spot. The surface of the eye is covered with photoreceptors that react to changes in the intensity of light. Impulses from all those receptors are transmitted to the blind spot, from where they transmitted via the optic nerve to the brain, where they are interpreted. However, there are no photoreceptors in the blind spot, so no image can be created there. What are the practical implications of this situation? When you close one eye, the picture seen by the other eye is incomplete. Therefore, the spots of both eyes are placed in such a way that a part of the world that is not seen b one eye is complemented by what the other sees.

However, this is not a defect that can be removed, e.g. with the help of laser vision correction. It is an imperfection of human body, shared by each one of us. A similar imperfection is the delay in reception of visual data occurring during the transfer from the retina to the appropriate area in the brain. Fortunately, the brain has the ability to reconstruct the reality and copes well with this situation. Therefore, it draws the missing elements of the image based on the core principles of the perception of the world around us.

The subject of optical illusions is so extensive that it is difficult to list them all. However, it is worth taking a closer look at it and checking how the illusion works.

Powrót