Again and again, motor neurons are mentioned in this paper and in this thread as what divides the consciousness-relevant bits of the em field from the rest. I propose something that at least to me seems far more reasonable.
After all, what makes consciousness so enigmatic is how private and personal the experience is; I can't reconcile that with a dependency on outward expression (here come the studies that show subvocalisation for our internal speech).
Memory. What is a flash of sentience in the dark? Our consciousness could be what it feels like to be an evolving feedback loop inside short-term memory, with input supplied by the outside world. So maybe there is field consciousness, and all the other sorts described in the paper, but what makes us self-reflective is the fact that we CAN reflect off of ourselves: our stored snapshots in memory. So I opine that the part of our EM field that can affect the memory encoding process is the part that is conscious.