I find that any kind of response time lag between my inputs and the real world, especially when it varies, is what makes me sick ...
My wife has vertigo. Her attacks can be triggered by fluorescent or high-pressure arc lights where the flicker rate is above the flicker-fusion rate of the eye. (This makes trips to warehouse stores problematic - they have to be short or she'll be down for the rest of the day. That's hard at, say, Costco.)
I used to wonder how this could be, and finally realized that the "strobe light" effect produces small, but significant, errors in observed position of the background items (shelves, etc.) that she uses for reference to balance despite the damaged inner ear.
When they first began using fluorescent lights in factories - in the days before guards over moving machinery were common - the worker injury rate went 'way up. Turns out the lights made the AC-powered motors, turning at or near an integer fraction of the line frequency, look like they were stopped or only moving slowly.
The fix was to build the light fixtures in two-tube versions, with a capacitor and an extra inductor in the balast, so the "lead lamp" and "lag lamp" would light at a quarter-cycle offset. In combination with suitably persistent phosphors this made them largely fill in each other's dim times, enough to make fast-moving parts blur and look like they were moving. For large arc lights, a similar fix was to arrange them so adjacent lamps were distributed among the three phases of the power feed, rather than having rows or patches of lights all flickering in unison.
Unfortunately, this lore has apparently been lost - at least outside the specialists wiring factories full of moving parts. Warehouse stores have rows and sections of arc lighting all wired to the same phase. I'm not sure, but I don't think the new electronic ballasts for flourescent lights do the lead-lag thing, OR have enough raw filtering capacitance to power the lamp through the phase reversals. (And then there's LED lamps...)
It's not a safety hazard these days, now that OSHA rules have all the fast-spinning machinery covered with guards. But for those with vertigo it's a big problem.