Stumbled at this video, and I'm amazed of this dr knowledge!!
Looks gaze fixation is measurable with infra red sensor by videonystagmography
https://www.youtube.com/watch?v=_wub7goUKIY&list=WL&index=8&t=82s

He also mentions Troxler effect test
https://3.bp.blogspot.com/-I--urWg6ogg/T9uPGhkpDhI/AAAAAAAAAz4/I_TV_GkHZGw/s1600/troxler+effect.jpg

I wonder how each of you reacts to this test! After a few seconds I lose the green and I see the red dot only, but each second-two I seem to move my eyes and I see different part of the green but mostly now the full circle.
I tested on my good chromebook and on my bad Mac and I don't feel much difference :S Also printed this test I think on paper was even harder to loos the green circle which makes not much sense, you would expect the opposite :S
Based on the video I understand ~15times/min moves are normal, where I think I do 35-40+. This + dithering might be our common issue??

This is another video from the same dr, talking about light sensitivity during post concussion. The weird part is this kinda mimic some of ours behavior, wearing dark glasses and baseball hats to hide from lights 😃
Interesting is that this dr. also talks about PWM, just does not mention the term only describes it.
https://www.youtube.com/watch?v=arK0zvX1KOc&list=WL&index=7&t=65s

btw I bought those green glasses
https://www.amazon.com/gp/product/B004BQSTF2/ref=oh_aui_detailpage_o01_s00?ie=UTF8&th=1
they don't seem to help for looking at a computer screen, however I observed some interesting behavior.
1. Once you get strained, wearing them seems to unstrain faster
2. I do not feel relief when looking at computer screen however when looking at iPhoneX they seem to slightly help, the white color is not shimmering anymore.
3. After wearing them for few minutes if there are LED lights in the room, once you take off the glasses your vision is slightly pink for ~30s (at least mines 😃)
4. I think you can even drive with them, mostly the white color becomes light green and you can directly look at car lights (any light source directly) without trouble at all, the red is still red, outside in the dark they do not distort reality as much as when looking at light screens.
I kinda liked them that I did not end up returning them, although not comfortable wearing them in front of anybody 😃

He is Chiropractic Neurologist in Canada, @JTL