I read a comment (perhaps here or on Reddit) explaining that different frequencies affect the eye and brain. That is to say, one set of frequencies may lead to more eye-specific symptoms (eye pain, dry eye, etc.) and others can affect different parts of the brain. And of course both can occur simultaneously or in conjunction. I have no idea as the the scientific specifics of this, but my own experience lines up.
I was accused of bringing up politics when I commented this on Reddit, but as I said then, this is my lived experience. I can trace my flicker sensitivities to a July 2022 COVID infection. To say that infection has changed my life would be an understatement. I won’t get into too many specifics here, but needless to say I have long COVID, now walk with a cane, and have a lot of health issues. And I’m only 32 years-old.
Prior to that infection I never really liked flashing lights. And yeah, in retrospect I can place eye strain to certain Apple computers (I’m looking at you iMac Pro) that had PWM, for example. But, I performed in and edited a music video with strobe lights in 2020. Not just a single scene - the entire video was strobe lights. I had no problems.
I got reinfected with COVID last summer and now previously used devices are unusable. Coincidence? Maybe. I don’t know. Almost every person on the planet has had COVID at least once. I’ve spoken to many other long haulers and screen sensitive individuals and many also started having problems after an infection. At the very least, it can’t have helped things, given what we know about vascular damage, neurological effects, and how it is a multi-system disease.
That being said, Apple is clearly utilizing PWM and dithering techniques in irresponsible ways. It has been present for nearly 20 years. Apple was actually sued in 2007 by photographers for their utilizing of dither (6-bit + FRC) - but for marketing reasons, not health reasons. You can read one such article here: https://arstechnica.com/gadgets/2008/03/apple-quietly-settles-lawsuit-over-dithered-laptop-displays/
It makes sense that Apple, now in control of their GPU and CPU chipset, is now ramping up these techniques in new ways.
If we assume that FRC is being used on every Mac with an internal display - and even the Studio Display - because it is well-established the only Mac with a true 10-bit display is the Pro Display XDR, then we have to assume that the frequency of that form of temporal dithering is low. And that it cannot be disabled through software means (for now) as it is occurring likely outside of the GPU command. So that’s a dangerous flicker - likely the gray color flicker. You couple that with the GPU dithering and PWM and it’s a nightmare of interactions. It’s no wonder none of us can pin down anything given the obfuscation that is Apple marketing and spec sheets.
So yeah, old Intel Macs cause eye pain for me and some brain fog. Apple Silicon Macs cause full-on tachycardia, nerve pain and tingling, and seizures. All within minutes. I’d settle for eye pain, to be honest. The neurological stuff is absolutely terrifying.
I will clarify I’m a special case. My health is pretty bad. And I could largely tolerate many of these screens prior. I can’t tell you whether the increase is neurological symptoms is purely my own health, or whether older chips and older operating systems also play a role. I’m working on testing that theory, out of pure desperation and frankly, anger. But I can tell you none of this stuff is benign just because others may not have immediate symptoms. I firmly believe, based on all of the posts I have read here, that this is a technology problem that is getting worse. We don’t know how looking at screens like this will affect the brain in 10, 20, 30 years. We won’t know.
There’s a lot of gaslighting going on in other spaces about this. I’m sorry, I’ve used computers since I was a kid in the late nineties - many of you for much longer than I. A forum like this never had to exist back then.
Accessibility options need to be made available. Apple can do it, it’s not hard. But it seems these days all they understand is a class action lawsuit. Perhaps it has come to that.
