I wouldn't take the leap into the Faraday cage so easily, that would imply that consciousness is measurable in the electromagnetic field. I don't think that's true, otherwise we would have measured it already. I don't know where to go next on this reasoning, it seems like we don't have the tools to measure in which field we are communicating.

That line of reasoning seems pretty silly given that consciousness is supposed to be much more subtle than electromagnetic fluctuations and omnipresent, but it reminds me of the Tibetan Buddhist tradition where the most difficult practices are only done deep in mountain caves where no light can reach the practitioner. I wouldn't be at all surprised if minimizing cosmic background radiation was a factor in sufficiently subtle inner inquiry.

One of my ancient aliens theories is that the Pyramids are artificial mountain caves.

Brain antennae + consciousness is more complex than just brain consciousness. In the former, we still have to answer "so... what is consciousness then? where is it? how does it couple to the brain? can it be blocked?" In the latter, it's just "consciousness is a property of a brain", and we are only left with the question of how the brain produces it. The antenna theory is just multiplying entities unnecessarily.