I is for Illusion

• By: mrbongo
• On: 07/01/2008 19:34:00
• In: Uncategorised
• Comments: 32

This week I've been learning about illusions, An illusion is a distortion of a sensory perception, the most common form being optical illusions. This is not to say that all illusions are optical though. The famous illusionist David Copperfield tried auditory, tactile and finally olfactory (smelly) illusions before settling on optical illusions, some people say he was the greatest olfactory illusionist ever to live but rumour has it that he gave up olfactory illusion in order to break into television (which at the time had no smellysence like it does today).

optical illusions are the most well known and understood form of illusion. The emphasis on visual illusions occurs because vision often dominates the other senses. For example, individuals watching a ventriloquist will perceive the voice is coming from the dummy since they are able to see the dummy mouth the words. This illusion is sometimes so good that parents fail to notice anything sinister about their children watching a show primarily about a man with his fist up a little boy's bottom grinning like a cheshire cat.

Some illusions are based on general assumptions the brain makes during perception. These assumptions are made using organizational principles, like Gestalt, an individual's ability of depth perception and motion perception, and perceptual constancy. Other illusions occur because of biological sensory structures within the human body or conditions outside of the body within one’s physical environment

Mimes are known for a repertoire of illusions that are created by physical means. The mime artist creates an illusion of acting upon or being acted upon by an unseen object. Unfortunately mime artists get too close to the illusion of these unseen objects and develop the belief that mime is actually art rather than tedious, this has been know to reduce their life expectancy

Mimes are often confused with clowns, the main difference is that a clowns stupidity makes his car doors fall off where as a mime pretends to mourn the loss of his car doors. Noone knows why.

Optical Illusions

An optical illusion is always characterized by visually perceived images that, at least in common sense terms, are deceptive or misleading. Therefore, the information gathered by the eye is processed by the brain to give, on the face of it, a percept that does not tally with a physical measurement of the stimulus source.

The Muller-Lyer illusion is one of the most famous optical illusions. It was created by German psychiatrist Franz Muller-Lyer in 1889. The Muller-Lyer illusion consists of two arrow-like figures, one with both ends pointing in, and the other with both ends pointing out. When asked to judge the lengths of the two lines, which are equal, viewers will typically claim that the line with outward pointing arrows is longer.



Unfortunately in 1891 a young psychiatrist called Funk Fritz-Gruber invented an illusion of much greater significance, Fritz-Gruber invented the worlds first physical illusion, he took Muller-Lyer's illusion and made it so that even if you measured the lines they would appear to be of different sizes, but really they are both the same size.
Muller-Lyer was devastated and dedicated the rest of his life to working out how Fritz-Gruber's illusion worked.

Auditory illusions

An auditory illusion is an illusion of hearing, the sound equivalent of an optical illusion: the listener hears either sounds which are not present in the stimulus, or "impossible" sounds. In short, audio illusions highlight areas where the human ear and brain, as organic, makeshift tools, differ from perfect audio receptors (for better or for worse). If you play one sin wave in your left ear and the opposite sin wave exactly one octave up in the other you can actually taste the colour green.

Olfactory Illusions

An olfactory illusion is an illusion of smells. The most noted olfactory illusion was David Copperfield's famous olfactory illusion. In this illusion Copperfield would shove 5 items up his anal passage a rose, a baby bell (small cheddar cheeze), a small slice of cake, a whole pineapple and a playing card. He'd then invite a member of the audience up on stage and get them to pick a card and show it to the audience. Copperfield would then blindfold the member of the audience and get them to smell a number of items in the opposite order starting with a miniature pina colada, a whole cake, a wheel of cheese, and a bouquette of flowers. As each object was passed under the audience member's nose he'd let out a fart of the opposite fragrance and get the volunteer to say what they smelled.
Once the volunteer had got each one wrong he'd get them, still blind folded to remove the playing card from his pert anus