There are hitters who have said that when they are ‘in the zone’ they can see the seams and make contact between them!
Maybe it is just a pattern, but they certainly believe they see the individual seams.
I played catch once with someone who was a pitcher drafted out of college and what surprised me was that I could actually hear the ball coming toward me. It really has a sizzling sound! Quite scary, and I had no interest in doing it again, even though he wasn’t throwing that hard. He could hit mid nineties with a lot of movement. He really threw more “junk” than “gas”.