In this illusion, created by Edward Adelson at MIT, squares A and B are the same shade of gray. (If you don't believe it, print it out and then cut out the two squares and place them side by side.) This illusion occurs because our brain does not directly perceive the true colors and brightness of objects in the world, but instead compares the color and brightness of a given item with others in its vicinity....[More]
BRIGHTNESS AND COLOR ILLUSIONS
In this illusion, created by Edward Adelson at MIT, squares A and B are the same shade of gray. (If you don't believe it, print it out and then cut out the two squares and place them side by side.) This illusion occurs because our brain does not directly perceive the true colors and brightness of objects in the world, but instead compares the color and brightness of a given item with others in its vicinity. For instance, the same gray square will look lighter when surrounded by black than when it is surrounded by white. Another example: when you read printed text on a page under indoor lighting, the amount of light reflected by the white space on the page is lower than the amount of light that would be reflected by the black letters in direct sunlight. Your brain doesn't really care about actual light levels, though, and instead interprets the letters as black because they remain darker than the rest of the page, no matter the lighting conditions. In other words, every newspaper is also a visual illusion!
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Edward H. Adelson
SHAPE DISTORTION ILLUSION
This illusion is known as the Café Wall illusion, and it was first discovered by Richard Gregory's laboratory in a café in Bristol, in the U.K. The black and white tiles are perfectly straight, but look tilted....[More]
SHAPE DISTORTION ILLUSION
This illusion is known as the Café Wall illusion, and it was first discovered by Richard Gregory's laboratory in a café in Bristol, in the U.K. The black and white tiles are perfectly straight, but look tilted. It is a shape distortion illusion: an object will appear to take on shapes that are different from its actual shape. Like brightness and color illusions, shape distortion effects are also produced by the interaction between the actual shape of the object and the shapes of nearby figures. For the brain, perception is very often dependent on context.
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ILLUSORY MOTION
Some stationary patterns generate the illusory perception of motion. The illusory effect is usually stronger if you move your eyes around the figure. For instance, in this illusion, invented by the scientist Akiyoshi Kitaoka, the "snakes" appear to rotate....[More]
ILLUSORY MOTION
Some stationary patterns generate the illusory perception of motion. The illusory effect is usually stronger if you move your eyes around the figure. For instance, in this illusion, invented by the scientist Akiyoshi Kitaoka, the "snakes" appear to rotate. But nothing is really moving, other than your eyes! If you hold your gaze steady on one of the black dots on the center of each "snake," the motion will slow down or even stop. Because holding the eyes still stops the illusory motion, we speculate that eye movements are required to see it. Vision scientists have shown that illusory motion activates brain areas that are similar to those activated by real motion.
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AMBIGUOUS FIGURES
This bunch of violets contains the faces of Napoleon, his wife, and their child. Can you find them among the flowers? During Napoleon's exile, his supporters used to distribute reproductions of this 1815 engravings....[More]
AMBIGUOUS FIGURES
This bunch of violets contains the faces of Napoleon, his wife, and their child. Can you find them among the flowers? During Napoleon's exile, his supporters used to distribute reproductions of this 1815 engravings. In such illusions, the brain interprets same picture in two different ways, with each interpretation mutually exclusive of the other. You can see one of two possible images, but never both of them at the same time. These so-called ambiguous figures are especially powerful tools to dissociate the subjective perception from the physical world. The physical object never changes, yet our perception alternates between two (or more) possible interpretations. For this reason, ambiguous illusions are used by many laboratories in the search for the neural correlates of consciousness.
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3-D ILLUSIONS
The cupola of the St. Ignatius's church in Rome is a great example of Baroque illusionism. The architect of the church, Horace Grassi, had originally planned to build a cupola, but died before finishing the church, and the money was used for something else....[More]
3-D ILLUSIONS
The cupola of the St. Ignatius's church in Rome is a great example of Baroque illusionism. The architect of the church, Horace Grassi, had originally planned to build a cupola, but died before finishing the church, and the money was used for something else. Thirty years later, in 1685, the Jesuit artist Andrea Pozzo (1642-1709) was asked to paint a fake dome on the ceiling over the altar. Pozzo was already considered a master in the art of perspective, but even then, the results he accomplished could hardly be believed. Even today, many visitors of St. Ignatius's are amazed to find out that the spectacular cupola is not real, but an illusion.
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Illusionism and perception have always played a very important role in ethe visual arts, from Classical Greece (with the Parthenon) to the present.. with the movies. IRENEALHANATI
For starters, one thing that has scratched my brain since I was about 10 is that, if it is a certainty that our perception isn't an accurate representation of reality (beyond the veil of maya), how do we know that the instruments we use to interpret information outside of our perceptive range are themselves interpreting "true" reality; are we blind-folk poking an elephant with a stick and calling it a wall?
Secondly, with regards to the slides, a similar one to slide 4 can be seen at http://visualfunhouse.com/hidden_images/lady-in-the-tree-optical-illusion.html
From what I'm told, most children don't see the naked woman.
& slide 3 I find Similar to the feeling you get when youre on a stationary train and the one next to you sets off; I usually experience the whole physical lunge effect as if it's the train I'm sat on that is setting off.
Another simple mental illusion Ive found is lying or sitting in a familiar room with your eyes closed, then convincing yourself that youre laid/sat the other way round; when Ive done this Ive actually felt the dimensions of the room change to fit my perception; then get a mild feeling of nausia when I open my eyes and the room's the wrong way round!
+1 final illusion; when you stare at a ceiling fan and relax your eyes (in the right kind of way), it appears to speed up, before switching into reverse... doesn't do your eyes much good tho'
As an invisible alien I object to wishywish talking about me as if I'm not here!
Also, what is up with your advertisers trying to download malware onto my machine lately? I mean really, don't you vet this junk before putting your site endorsement on it?
Adding Sugar to Bioscience
Owl's Ability to Link Sight and Sound Could Be Key to Treating Attention Disorders
13 Comments
Add CommentIllusionism and perception have always played a very important role in ethe visual arts, from Classical Greece (with the Parthenon) to the present.. with the movies. IRENEALHANATI
Reply | Report Abuse | Link to thisFor starters, one thing that has scratched my brain since I was about 10 is that, if it is a certainty that our perception isn't an accurate representation of reality (beyond the veil of maya), how do we know that the instruments we use to interpret information outside of our perceptive range are themselves interpreting "true" reality; are we blind-folk poking an elephant with a stick and calling it a wall?
Reply | Report Abuse | Link to thisSecondly, with regards to the slides, a similar one to slide 4 can be seen at http://visualfunhouse.com/hidden_images/lady-in-the-tree-optical-illusion.html
Reply | Report Abuse | Link to thisFrom what I'm told, most children don't see the naked woman.
& slide 3 I find Similar to the feeling you get when youre on a stationary train and the one next to you sets off; I usually experience the whole physical lunge effect as if it's the train I'm sat on that is setting off.
Another simple mental illusion Ive found is lying or sitting in a familiar room with your eyes closed, then convincing yourself that youre laid/sat the other way round; when Ive done this Ive actually felt the dimensions of the room change to fit my perception; then get a mild feeling of nausia when I open my eyes and the room's the wrong way round!
+1 final illusion; when you stare at a ceiling fan and relax your eyes (in the right kind of way), it appears to speed up, before switching into reverse... doesn't do your eyes much good tho'
Ambiguous figures:
Reply | Report Abuse | Link to this"You can see one of two possible images, but never both of them at the same time."
Uh yes I can. It's pretty easy actually.
That's true... we don't see all the invisible aliens running around here.
Reply | Report Abuse | Link to thisAs an invisible alien I object to wishywish talking about me as if I'm not here!
Reply | Report Abuse | Link to thisAlso, what is up with your advertisers trying to download malware onto my machine lately? I mean really, don't you vet this junk before putting your site endorsement on it?
In the SHAPE DISTORTION ILLUSION (2/5) If you tilt your head to the sides all those square wont be distorted anymore
Reply | Report Abuse | Link to thiscool
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Reply | Report Abuse | Link to thisEye Illusions are awesome
Reply | Report Abuse | Link to this<a href="http://www.google.com">Cool indeed!</a>
Reply | Report Abuse | Link to thisvar link = $(this).html();
Reply | Report Abuse | Link to this$(this).contents().wrap('<a href="example.com/script.php?id='+link+'"></a>');