It is a conundrum indeed to design experiments quantifying something we can't even detect, as researchers into dark energy and matter surely lament. Just as they indirectly have evidence in the motions of the heavens, researchers into consciousness have only indirect evidence to go by. You well point out what we mean by consciousness is a major hurdle to such experiments, demonstrating we know so little our language but poorly identifies what we are discussing. Studies of precognition are hampered by the inability to create reproducibility, limited to case studies, far from the gold standard of research.

It is indeed not your specialty, but I thought you might find it interesting, as we wonder from time to time what we really are.