Not colorblind. I have no central vision in my right eye. My
   brain uses it as an extension of the eye that works. [it's not
   great either but glasses work]. I'm also functionally deaf in my
   left ear, right ear only goes up to 5000 hz, yet I have perfect
   pitch [both kinds]. Some people have said I seem to have
   synesthesia. They speculated that because of how I describe my
   experiences. But I dunno - I think everybody has synesthesia.
   It's everyday and embedded in our languages. With music, I can
   distinguish many instruments playing at once and keep track of
   them. Yet, I get overwhelmed by too many moving items on
   tracking tasks... YET, if I have to "guess" at a count, I'm
   usually pretty close. [I can also see a pile of groceries and
   tell you how much it is within a few seconds and be within $5].
   All stupid stuff. Somehow I think they're related to this but I
   dunno. They also diagnosed me with cerebral palsy and put me in
   physical therapy between 2-4 yrs old. I was able to enter school
   regularly without anybody noticing anything but me being a
   little "weird". So, I dunno if any of this helps you or gives
   clues... but I look forward to your stuff on the subect. Optical
   illusions don't always work on me, which is disappointing,
   although I'm glad for the ones that do. == Also, I regularly
   work with massive amounts of data. I like seeing it "all at
   once". I use Excel frequently and "seeing everything" is
   important when I work. So it might be training: I tend to see
   the "whole thing" at once and go inwards, picking up what seems
   important from the whole picture, rather than focusing on
   something within and going outwards. hard to put into words.
   Just trying to give potential data. == Oh that was fun. I love
   the experience of the changing patterns while I was reading.
   I've done these before but was a really nice one. I love trippy
   stuff. But yeah, my eyes recovered as soon as the video was
   done. I suspect I'm -probably- on a permanent trip tongue
   emoticon Got used to seeing shadows moving on their own and not
   being afraid of them and stuff from when I was a kid. Maybe
   being extremely nearsighted, I never fully trust that I'm seeing
   what I think I'm seeing, yet I've learned that 99.999999% of
   anything out there is nothing to be frightened of. So, I dunno
   if it's related. == I think the problem with the OP for me is
   that I instantly saw them as mirrors of each other and did a
   quick side-to-side matching. Maybe if they were done separately
   it might work better, but together, it didn't work for me. ==