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quirkot | on: Insects don't swarm at LED lights
I wonder how much of it is also the LED flicker. If I was a small bug and moving quickly with a high visual refresh rate, I would probably hate the experience of the LED flicker
worldsavior | parent
There is no such thing as refresh rate for any kind of eye.
throwaway219450 | root | parent | next
There are odd visual illusions though, like humans perceive the Wagon-Wheel Effect even though there's no obvious reason it should happen. This is the effect where the speed of a rotating object varies depending on its sync with a discrete exposure period.

https://en.wikipedia.org/wiki/Wagon-wheel_effect

https://research.tue.nl/en/publications/subjective-strobosco...

qqewqe123 | root | parent
You mention it yourself, these illusions only occur with "discrete exposure periods". This is moreso related to video recordings and less about how the eye sees actual physical objects. Such illusions do NOT occur with natural light.

Edit; to be clear there is a version of the wagon wheel effect under natural light, I'm just saying that the main one with discrete exposure periods does not occur irl

throwaway219450 | root | parent | next
> You mention it yourself, these illusions only occur with "discrete exposure periods".

Have a look at https://www.pnas.org/doi/epdf/10.1073/pnas.93.8.3693; my point was that there is documented research that says even with continuous illumination and an (apparently) continuous camera (the brain), this happens:

> The illusion of wheels or other radial patterns rotating back- ward in continuous light, together with the perception of supernumerary spokes, suggests that the human visual system processes sequential episodes of information rather than a continuous temporal flow. In addition to accounting for this remarkable illusion, a strategy of vision that parses the world in this way can explain why movies are so realistic (simply because that is the way we normally see things) and how we detect motion (by comparing the position of the same objects in sequential episodes).

1718627440 | root | parent
What? Have you never looked at another car's wheel on the highway? Or is that something that only occurs to some people (doubt it).
autoexec | root | parent
Eye vibrations can cause the effect to be visible to the naked eye. If even humming can do it, the road vibrations might too.
1718627440 | root | parent
I'm confused. I thought seeing/measuring lower frequencies due to a low sampling frequency, where the lower perceived frequency is basically the modulus of the real frequency and the sampling rate, is a well-known phenomenon independent of the actual sensor implementation.
autoexec | root | parent
I guess it is, but it's unclear why it happens outside of recordings. https://www.livescience.com/32406-what-makes-wheels-appear-t...
stevenwoo | root | parent | next
I highly recommend the pop science book An Immense World by Ed Yong to disabuse you of this notion. There is a sort of refresh rate (not exactly the same but good metaphor) for everything at every level of living being we study. It gives enough information for you to read the actual studied should you have more questions after reading it.
nine_k | root | parent | next
There is for the visual cortex though.

Try walking outside in a clear night. Look up, notice some stars, or aircraft lights. Now rotate in place, and see how low your vision's FPS is in the dark: the rotation will be visibility jumpy.

An insect, with its much simpler visual processing, and facing a bright light, will likely achieve a much higher FPS, sufficient for the sub-kilohertz flicker to be very visible.

IanCal | root | parent | next
Are you thinking about saccades? I don’t think I’ve ever seen what you’re talking about with non-flickering sources.
inexcf | root | parent
For a game i tried to model the behavior of our eyes in the dark and read up on a lot of that stuff. Not once was there a suggestion of jumpy vision. And that is also not my experience. In low light things begin to smudge, lots of ghosting the further in the periphery of your view they move in.
quirkot | root | parent | next
Yeah, i know that's how the physics works, but effectively my computer monitor doesn't flicker for me but a strobe light does. Whatever the proper term for that is what I'm talking aobut
jschveibinz | root | parent | next
But there is a neurological component in "optical processing" that can be modeled as a discrete rate of update although the underlying physiology is still being investigated.
andai | root | parent | next
I can often see the refresh rate of lamps, especially out the corner of my eye.

I'm told insects are more sensitive in that regard, due to having brains with fewer layers.

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smallmancontrov | root | parent | next
Nyquist had something to say about that.
DoctorOetker | root | parent
It's called the flicker fusion threshold.