Our eyes can't really "process" any FPS. Our eyes aren't cameras and don't really work the same way.

We do know, though, that 24 frames per second is the minimum amount after which we perceive a series of pictures as motion rather than individual shots. But just because that's the minimum doesn't mean we can't benefit from higher rates -- and apparently we do. 24 frames per second looks like motion, but 60 fps looks like smoother motion, and 144 fps looks even smoother, etc. There's probably an upper limit, too, and at some point it does become meaningless marketing stuff, but hey.