I don't see that we currently have a a thread devoted to the relationship between optical phenomena, like the attached video, and how they relate to anticipations / prolepsis.
In this example, when you play the video you see pretty clearly the outline of a shape. When you stop the motion the outline largely if not fully disappears.
I think it's pretty clear from our past discussions that we do not think Epicurus would tell us that the eyes themselves are seeing this shape. So is this a functioning of prolepsis/anticipations that the mind is assembling from repeated viewing of the object the pattern that is created in this example?
I think optical examples like this can help us clarify our use of the anticipation / prolepisis phenoma along exactly the lines Lucretius discusses in book four of his poem.
(Note that the music came with the video - not mine - and you may want to mute it.)