Sometimes I try to watch myself make a decision, like deciding to lift my arm. I've got my arm there, and I'm going to lift it.. at some point.. and I wait and wait for the decision to be made, because I want to watch it be made.. but it doesn't happen. I can lift my arm, of course, but I can't seem to watch myself make the decision to do it. This feels related to a turing machine figuring out what it is going to output before it outputs it.
I can watch myself do things, like walking. Things that I've already decided to do, and that are run by some unconscious process.
I can also think really hard about lifting my arm, and if my arm is already in the air a little bit, it will actually lift, very slowly, in little bursts, where these little bursts are not decided by my conscious self. I feel like hypnosis is related to this (in part because someone who tried to hypnotise me had me do exactly that process as part of the hypnotic induction — however, it happened very slowly, and I failed to become hypnotized, as far as I recall ;)