apeiron said:
Digging into it a bit more, I see he is also tied in with this lot...
http://www.consciousness.arizona.edu/WorkshopSynesthesia2012.htm
So a lot of bad science behind the bad journalism.
Yes.
Here is Padgett describing his symptoms first hand in a short clip...
His description of trailing and jitter effects are not synesthesia at all in my book. More the kind of visual disturbances that you get from brain damage that results in integrative failures in the visual hierarchy. Or Hallucinogen Persisting Perception Disorder (HPPD).
A guy I know here, who's been diagnosed as somewhere on the autistic spectrum, described this same difficulty with following the motion of cars or busses to me. He said nothing about a grid, but he said things to the effect that, to him, cars jerk forward in space rather than progress with continuous motion. He mentioned this several times in several different conversations, so I take it it was quite intrusive. He complained that he can't read the signs on the sides of busses when they are in motion because he can't visually track them. No one else I have met who has Asperger's has mentioned this (though none of them seems to have ever had a driver's license).
Sacks mentioned a woman whose visual field would freeze and stick due to the sight of certain motions. Pouring tea was one trigger. The scene would stop moving and become a still frame of tea coming out of the pot into the cup, and she'd be stuck there a while. That's not synesthesia, and this jerky motion effect sounds like a quick succession of shorter lived episodes of it.
There is a wiki page claiming that brain scans show he only reacts to actual fractal equations, but I've not been able to track down the papers as yet, so that looks like unpublished stuff. And given the other information, I would still be dubious.
However, giving the case for the other side (because whatever the explanation, it is interesting the spin that is getting put on all of this)...
And here is a clip which suggests the test stimuli were actual objects rather than equations. Possibly this was just a different experiment, but it does give yet more first-hand accounts of what Padgett experiences, and ties it to motion processing issues.
The only synesthetic sounding thing here: In the last video he says the sound of the MRI made him see wavy lines, but only, "in my head". That's ambiguous, and I wouldn't assume synesthesia from it.
If the sight of the formula for a fractal causes him to see the pattern of a fractal, I still wouldn't call that synesthesia, just hallucination. I wouldn't call him a savant either, unless they've conclusively determined that the image he sees is the one that would, in fact, be generated by the formula they showed him.
I have an inkling he may only be seeing "form constants". Hallucinogenic drugs, and many other things that affect the brain cause people to see geometric patterns that a guy named Kluver dubbed "form constants". (Migraine aurae are another well known cause of this.) :
It is believed that the reason why these form constants appear has to do with the way the visual system is organized, and in particular in the mapping between patterns on the retina and the columnar organization of primary visual cortex. Concentric circles in the retina are mapped into parallel lines in visual cortex. Spirals, tunnels, lattices and cobwebs map into lines in different directions. This means that if activation spreads in straight lines within the visual cortex, the experience is equivalent to looking at actual form constants.
http://en.wikipedia.org/wiki/Form_constant
I suspect this guy may be seeing form constants but was mislead into believing they were fractals. Now he leans in that direction by confirmation bias and "fractalizes" his reports of what he sees, justifying it with the phrase he repeated often in the last video: "Everything's a fractal."
The Danish researcher strikes me as being synesthesia-happy, much like Richard Cytowic, who seems to see synesthesia everywhere (and came up with the statistic of 1 in 10 people having some form of synesthesia).
Anyway, since he's been tainted with the notion he's some kind of mathematical genius now, and that's been linked to fractals, it may not be possible any longer to determine whether or not all he's been experiencing are form constants. He may have trained himself to visually conflate them with all the images of fractals he's now seen on the web.