You know roughly where your body is at all times, but where in it is your "self"?
Your center of mass is around the solar plexus, yet that doesn't seem to universally be where people feel the center of their self to be. Most people feel they "are" right behind their eyes, probably in the brain.
Sometimes people have out-of-body experiences, completely changing their anchor for a while.
When pointing at themselves, people tend to point a thumb at their chest or face. Do they feel differently about it, or is it just convenience?
Are you a body with a head full of thinking goop and sensors on top, or are you a head sitting on a body?
And wherever you feel you are, have you felt different at any time? Can you change it?
Personally, I can't separate the feeling of self from my vision, so "I" am directly behind my eyeballs and I can't change it.
I have a remarkable connection to reality when I eat mushrooms, it seems. I can just point my brain in a direction and it will go as far as I let it. For me, and I don't know what to call it, I have an interesting "reality bubble" that I can "stay in" if I desire. It's a part of my brain that knows that everything I am seeing is not real and where I can make somewhat decent choices if I need. I have a tripping inner dialogue as well as a "normal" internal dialogue that keeps me sane. It's... Interesting.
If I have a task to do, like drawing something or working in CAD, it will keep my brain somewhat focused albeit with a ton of added flair.
And no, I can't control all of my thoughts but those still remain somewhat superficial and are not really that intrusive. However, letting my mind go free and letting me think about things from a different perspective is probably the primary reason I trip. My personal mental barriers that I have put up over the years are needing to be torn away so I can become the good person I strive to be and deal with some aspects of my past in a somewhat healthy way. I have no fear of a "bad trip" as I view it as an aspect of my life and personality that needs further exploration.
I should note that I have a very high tolerance and psilocybin is a perfect match for my personality type and brain chemistry. (Weed, for example, gets me super paranoid and is not for me.) I can easily eat 5-10 grams just to get me started and have eaten as much as 20 grams throughout an evening.
Short term memory loss is a thing as well. I can completely forget what it was a wanted to think about, but after a bit, I can usually get focused on something. What usually happens is that my brain figures out the solution to the problem I wanted to think about extremely fast so there is not much to ponder on. :P