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The optical motional illusion shown below, makes your brain see some motion, where there is none.

enter image description here

In my opinion it's fascinating, although after a while you get a headache. It reminds me of binaural beats, where the brain simulates the difference tone, which is obviously not there. The way that these illusions work is obviously quite different than how binaural beats work, as stated in the comments.

Despite that, it's said that the beats stimulate your brain, so my questions are

  1. What is the name of this optical illusion?

    Akiyoshi Kitaoka studied these kind of optimized Fraser-Wilcox illusions.

  2. Does it affect the brain in a similar way to binaural beats? I mean the overall effect, not the specific way how Fraser-Wilcox illusions or binaural beats enter your mind.
For those who liked the previous picture, here it is:

enter image description here

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I don't really see why it would be related to "binaural beats" at all. Visual and auditory "illusions" have very different causes. In addition the "effects" of biaural beats are largely in question at best it sounds like "binaural beats" are very similar to white noise in terms of their relaxing "effects. – Ben Brocka Jun 1 '12 at 15:14
@BenBrocka I don't think the OP meant 'similar' as in 'using the same neural mechanism' but as 'producing similar qualia in a different domain (i.e. visual instead of auditory). – Artem Kaznatcheev Jun 1 '12 at 15:22
More to the point I think you should focus on asking one question at a time; what is the name of/causes this sort of illusion seems like an okay, answerable question, it's relation to binaural beats seems very tenuous unless you have some reason to believe there are similar causes/effects – Ben Brocka Jun 1 '12 at 15:23
@ArtemKaznatcheev then the question is...what qualities? I don't really see a perceived tonal difference as being anything like perceived movement due to spatial patterns – Ben Brocka Jun 1 '12 at 15:26
@BenBrocka, the question on the name might be omitted. I thought somebody here would know it. The question of most interest to me is: Do these kind of pictures stimulate your brain? – draks ... Jun 3 '12 at 20:52

Binaural beats result from a difference between the stimulus presented to each ear. The brain tries to integrate them and the perceived low-frequency beat is an artifact of that processing. There are optical illusions that involve presenting distinct, isolated inputs to each eye, and I'd consider those the closest equivalent to binaural beats.

The apparent motion in the image doesn't rely on binocular vision; you can see that easily by looking at it with one eye closed (in fact, I think that makes it stronger). I'd guess it's probably based on edge detection or lateral inhibition, which don't (I think) have a particularly close analog in sound perception.

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I've tried looking at this image in greyscale and I still get the illusion. So it doesn't seem like the illusion relies on chromatic information. The effect is definitely weaker however, so it might be the case that the illusion relies on common properties of the colour and non-colour visual pathways (e.g., parvocellular and magnocellular), however we would need an isoilluminant chromatic version of the stimuli to be sure.

Maybe the following article will provide the answer.

Cropper, S. J. & Wuerger, S. M. (2005). The detection of motion in chromatic stimuli: A critical review. Behavioural and Cognitive Science Reviews, (Invited for publication).

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A comparison of color and grey scale can be found here. – draks ... Jun 4 '12 at 17:24

Akiyoshi's website answers the first of your questions. He calls it the peripheral drift illusion.

The Rotating Snakes illusion is the culmination of a long series of modifications that Akiyoshi made to enhance the peripheral drift effect, that was discovered by Fraser and Wilcox. In 2003 he wrote a paper describing his work, but admitted that all he had was rules to enhance the effect, but not an explanation for it:

Although this study only reveals phenomenological or design rules to obtain the peripheral drift illusion with large illusion magnitude, we are seeking an explanation on the basis of motion detector models.

His publications page shows a new (2012) paper which offers a more comprehensive explanation based of fMRI studies of the primary visual cortex, V1. If you have Elsevier access you can read it here. Yet another reason why publicly funded research should have public access.

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