There's actually a sort of native refresh rate in the eye but it isn't exact and afaik no one has really figured out how it's coded. I think I read that there i

There's actually a sort of native refresh rate in the eye but it isn't exact and afaik no one has really figured out how it's coded. I think I read that there is a regular drip from one layer of the retina that provides a sort of baseline rate that deviates upwards when that pathway is excited. Don't quote me on that though...