[amatic]

Well, it is not "brain activity alone", there are always light waves, forces, chemicals, and a lot of other things, acting on the brain from "outside" of the body, through some very strange receptor routs, but the "information" somehow travels. And we know 100% that for a lot of receptors, the firing rates depend on the intensity of the stimulus. So, we can see a direct correlation between, say, an applied force and golgi tendon organ firing. And at the same time, we discovered some types of radiation that we cannot see, and yet they can influence distant objects. I think that is pretty weird. So, we found a lot of direct correlations between brain activity and the outside world. Is there some need for an additional invisible field, not covered in current physics?