The brain controls what we see because it is the optic nerve behind the eye, connected to the brain, that allows us to reconstruct the images we see.
But our brain sometimes makes mistakes! Whether it's tricked by optical illusions, subliminal images, camouflage, mirages, trompe-l'oeil, or a phenomenon known in ophthalmology: the blind spot, we're going to reveal all.
What is an optical illusion?
It's a visual perception that differs from reality, a mental distortion of an image due to an erroneous interpretation by the brain. For example: can you tell which way this subway is going?
What is a subliminal image?
A subliminal image is an image that is undetectable to the naked eye but that the brain would process anyway. For example, in the middle of a film, an image might be flashed for such a short time that we wouldn't have time to see it, yet the brain would see it and integrate it into our subconscious.
What is camouflage?
Camouflage is a technique aimed at creating an optical illusion to avoid being seen. Chameleons are kings of it!
What is a mirage?
It is a phenomenon of light reflection coming from a region where the air is cool and entering a region where the air is warmer. Thus, light rays become curved. Objects are duplicated by an inverted image, making one believe in a reflection on a body of water. Mirages can be observed especially in deserts or on roads.
What is a trompe-l'oeil?
It is a painting that creates the illusion of reality, through an excellent rendering of the object's relief, thanks to the interplay of shadows and light. It is an art known and practiced since antiquity.
What is the blind spot?
It is the only point on the retina where we cannot see, due to the absence of photoreceptors. It corresponds to the place where the optic nerve and blood vessels leave the eye.
