Visual Deception

Visual phenomena or what we normally call as ‘Optical Illusion’ involves visual deception. A wide range of optical illusions happen in our day to day lives, like seeing a rainbow after a rainy day or even while staring at clouds; In this phenomenon, the human brain tends to develop different pictures to interpret the shape, curve, and size of the clouds.

Optical illusions are just cases of errors in judgment; they do not physically exist. Our eyes capture light from an object that emits or reflects light and focuses the images upon the retina where messages are then carried on to the brain.

The retina is found at the back of the eye and it contains cells that respond to light. The retina, when hit by light, triggers nerve impulses which are then sent to the brain, the brain, in turn, interprets the data coming in as light and shadow, form and colour (Bruno, 2011). The eyes are an important part in an optical illusion; it is the connecting link between what is real and the illusion itself.

There are three main types of optical illusion: literal illusions, physiological illusions, and cognitive illusions. Most of the illusions were discovered by psychologists and later, people started using these effects to create new illusions for entertainment and amusement such as magicians and illusionists.

Literal illusions create images that are different from the objects that make them. Physical or literal optical illusions occur when objects appear differently. This illusion happens before light enters the eye.

An example of a physical illusion is a Rainbow; the sunlight reflects through water droplets in the air and forms a colourful rainbow across the sky (Richards, 2002).

Physiological illusions are the effect on the eyes and brain due to excessive stimulation of a specific type, such as brightness, tilt, colour, movement etc. The most well-known effects are the afterimages following bright lights or when you stare at a moving or still image for a long time and see other things move after that or when the image starts moving on its own (Anastasia. 2009).

Cognitive illusions happen when the eyes and brain makes interpretations and perception. Seeing two different objects in the same picture is an example of cognitive illusion. Cognitive illusions are divided into four types, firstly, ambiguous illusions. Ambiguous illusions are pictures or objects that show a shift or change between the illusions. Secondly, distorting illusions, they are characterized by distortions of size, length, or curve, while paradox illusions are created by objects that are paradoxical or impossible. Lastly, fiction illusions, also known as hallucinations, are defined as the view of objects that are generally not there to all but a single observer (Anastasia. 2009).

The capacity for the human mind and the capacity of the eyes often lead to interesting, hilarious and entertaining visual images that do not really exist. These optical illusions are normal parts of the human experience.