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The Neuroscience of Illusions and Dictionaries

Posted by Soulskill on from the maybe-your-brain-is-just-a-jerk dept.

Scientific American is running a pair of stories about what words and illusions can tell us about the brain. Mark Changizi of the Rensselaer Polytechnic Institute is interviewed about his research into the relationship between the mechanisms of the brain and the evolution of language. The second article contains a slide-show of various illusions and why the brain interprets them as it does.

4 of 72 comments (clear)

  1. So can somebody explain? by quokkapox · · Score: 3, Interesting

    Why do LED clocks jiggle up and down when I'm eating crunchy things?

    --
    it's a blue bright blue Saturday hey hey
  2. Binocular vision and elephants by Red+Flayer · · Score: 4, Interesting

    For the evolution of forward-facing eyes, I am arguing that it is for a kind of x-ray vision. It actually allows us to see through stuff--like when you hold up a finger vertically and you see through it instead of beyond it. For animals that are large and living in forested environments, there should be selection pressure for forward-facing eyes, because you can actually see more of your environment.
    That makes a lot of sense, and is very interesting to me since I recall learning that predators have forward facing eyes so they can better detect movement of prey (binocular vision) while prey animals have outward facing eyes so they can better be aware of threats (greater field of vision).

    I had always wondered why elephants had forward-facing eyes, since they are not predators... and this helps explain it. I had always supposed that it was because they were social animals, and communication ability and multiple individuals scanning for threats was better than one individual with a larger field of view. This makes even more sense if the scanning in a smaller area is more effective due to the binocular vision associated with forward-facing eyes.
    --
    "Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
  3. More/Better Optical Illusions by martyb · · Score: 5, Interesting

    The second article contains a slide-show of various illusions [CC] [GC] and why the brain interprets them as it does.

    Maybe I missed something, but I found the second article to be a let-down.

    (Warning for epileptics: if visual stimuli can set off a seizure for you, you should probably stay away from the following links. I am not susceptible, but I found the second link to be visually overwhelming at first.)

    IMHO, more interesting galleries of examples can be found at Wikipedia's Optical Illusions page and at Michael Bach's 78 Optical Illusions & Visual Phenomena page.

  4. Re:Brightness and Color Illusions by hansraj · · Score: 3, Interesting
    As always wikipedia is your friend. The reason for this illusion is summarized in the following line:

    When interpreted as a 3-dimensional scene, our visual system immediately estimates a lighting vector and uses this to judge the property of the material. So, in effect the brain sees something that looks like a 3D image and imagines that there is a source of light somewhere. If you look at the picture again, you would notice that the perceived color difference of the two squares appear distinctly with a mental image of a shadow of the cylinder on the chequered platform. The brain imagines a light source on the upper left side of the picture. Why exactly there? Probably because the cylinder seems to have a lighter shade in that direction and darker on the opposite side, making it seem as if there is a light source in that direction.

    Fascinating really!