The basic neurobiology behind the 12-dot illusion
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The basic neurobiology behind the 12-dot illusion
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Re: The basic neurobiology behind the 12-dot illusion
#2This was a fascinating read about the neurobiology of the visual system. Loved it!
Re: The basic neurobiology behind the 12-dot illusion
#3The fovea, the area of high-resolution vision in the middle of the field of view, is surprisingly small, just a few degrees across. The resolution falls rapidly outside the fovea [1]. A lot of the detail we perceive in the periphery is actually the brain filling in blanks based on "cached" data.
The resolution drop could in principle be taken advantage of in computer graphics, especially in VR applications with robust enough eye tracking [2].
Re: The basic neurobiology behind the 12-dot illusion
#4I found that once I zoomed in to have only 6 dots on the screen and zoomed out, the illusion disappeared and I was able to see the 12 dots simultaneously.
I tested it on a friend and same thing but he had to stay zoomed in longer than me, for me it was instant, he had to stay focused 5 or 10 seconds.
And now I can't not see the 12 dots even 48 hours later without being exposed to the image.
Re: The basic neurobiology behind the 12-dot illusion
#5The fovea, the area of high-resolution vision in the middle of the field of view, is surprisingly small, just a few degrees across. The resolution falls rapidly outside the fovea [1]. A lot of the detail we perceive in the periphery is actually the brain filling in blanks based on "cached" data. The resolution drop could in principle be taken advantage of in computer graphics, especially in VR applications with robus…
Hah, why not.. We already created perceptually correct audio CODECs. Doing the same for real-time image generation seems like a worthy research area for sure!
Re: The basic neurobiology behind the 12-dot illusion
#6I found that once I zoomed in to have only 6 dots on the screen and zoomed out, the illusion disappeared and I was able to see the 12 dots simultaneously. I tested it on a friend and same thing but he had to stay zoomed in longer than me, for me it was instant, he had to stay focused 5 or 10 seconds. And now I can't not see the 12 dots even 48 hours later without being exposed to the image.
I'm replying to you rather than making another top level comment to prevent sprawl, but I'm adding a different way the effect changed for me. (I'll probably try yours later, when I'm done playing with it, lol)
For me, holding a "picture" of what the picture is in my head and trying to heat map where I think my view is spotting the dots changed it from seeing about 4 (in a triangle or box) to about 6 (in weird squiggles). I think that actively trying to see it changes how my brain caches information as it moves the eyes' focus.
Re: The basic neurobiology behind the 12-dot illusion
#7The way the eye interfaces with the brain never ceases to amaze me. Another fun fact is that it even has it's own error correction mechanisms, one of which you can intentionally miscalibrate in order to see colors that aren't there for days, weeks, and sometimes even months after doing the calibration (which is acheived by looking at a very specific image pattern for a long time). I would not recommend actually doing this, as those who have have reported back that the illusory colors become quite distracting and actually cause a bit of emotional distress after many months, but it's crazy that the brain has this kind of chromatic abboration error correction programmed in in the first place. https://en.wikipedia.org/wiki/McCollough_effect
Re: The basic neurobiology behind the 12-dot illusion
#8I'm not sure the central argument fully explains the illusion.
If you can simultaneously see several stars in the sky using your peripheral vision using averted gaze, why not several dots?
I suspect uncertainty plays a part, but image completion from higher-order feedback that complete the lines might drive the illusion more. Put another way, I believe if you remove the gray lines, the illusion ceases to work.
Re: The basic neurobiology behind the 12-dot illusion
#9I was looking into this when the 12-dot illusion came out, and found an interesting refutation of the receptive field theory regarding a related illusion - the original Hermann grid. I'm not sure if it also applies to the 12-dot illusion, where the illusion seems to be more about foveal/peripheral accuracy.
You can read about it here, and play with a demo:
http://www.michaelbach.de/ot/lum-herGridCurved/index.html
http://web.mit.edu/bcs/schillerlab/research/A-Vision/A15-2.h...
Re: The basic neurobiology behind the 12-dot illusion
#10It's pretty surprising to learn how fast visual acuity falls off outside the fovea. Our brains are amazing at making us think we can see a wide field of view when we really can't.
This article was great, fun to read. I think this chart summarizes the whole thing:
If you fixate on the dot in the middle, all letters are equally legible to your eyeballs. This lets you see directly the difference in resolution between your fovea and your peripheral vision.