What Michi was describing is a demonstration of how your brain actually processes objects in your environment. It’s fairly difficult to see this with yourself, because of body awareness. When you have a partner, it’s a little easier to notice, because you have no other feedback regarding where their hands are. Even then, this is a tricky phenomena to demonstrate naturally in a controlled environment, because of how your brain works.
So, as it’s been explained to me several times: When you see things, you filter objects based on finding their edge and using that to separate the them from the environment. Movement helps to define the edges, but it’s not necessary.
Usually this comes up when talking about how camouflage works. Camo breaks up that outline. So, when you can’t see the silhouette, so your brain doesn’t process something’s existence until you start finding the edges.
That said, there are tons of optical illusions out there that trick your brain into creating something that doesn’t exist, by feeding just enough outline data to you that it does the rest.
When we’re talking about people, it’s slightly easier to track their silhouette, than it is to parse them inside that. It’s not that you can’t see their hand, it’s that it’s easier for your brain to say, “yep, that’s a person, I’m done here,” then to keep track of each individual part of them separately.
In combat, you can exploit this, by keeping your arms inside your silhouette. It camouflages your movements a little. This is a fairly minor advantage, but it is one more you can slap on the pile.
Martial Arts training doesn’t affect the way your brain processes information from your eyes. We’re not being literal when we say, “martial arts training changes the way you see the world.” It changes the way you understand and interact with your world, but it doesn’t change the way your eyes work.
That said, martial artists are more likely to be keeping track of someone’s hands, if they’re worried something will happen. Which means they’re already parsing their opponent’s limbs.
-Starke