okay it might be partly nonsence what i said.
i did some more research and found something more reaonable.
the cells in your eye can catch up to a certain amount of frames per second.
this for the simple reason that it is a chemical reaction that takes time.
the brain on the other hand can combine all those cell information into a smooth image.
while one cell would maybe give information ten times every 1 second 10 fps.
the eye in a whole gives constantly information to the brain due to the cells not being "alligned" (if thats the proper word).
Therefor the whole eye will give a much higher fps than one cell.