"...when they were deeply asleep and therefore unconscious."<p>Advanced meditators are able to be vividly conscious in deep sleep. Though it's probably impossible to describe, the closest might be "consciousness without content." It's subtle enough that most of us overlook it.<p>Even something as common as lucid dreaming took centuries to be taken seriously. The community at large insisted that it was a delusion. We are probably years away from being able to make sense of the claim that we can be profoundly conscious in deep sleep. Perhaps that can only happen when more of us are trained well enough to experience it for ourselves.<p>I'll be eager to see how society integrates these kinds of understandings into end-of-life issues, if I'm still around.
I find the wording "detecting consciousness" problematic. They are not detecting consciousness as if they were detecting subatomic particles in a cloud chamber, or pollutants in the water; they are just measuring some neural fireworks that they believe coincide in time with the reported subjective experiences of the patients.<p>Then there's this:<p>> The current most promising scientific theory of consciousness [...] is Integrated Information Theory (IIT). [...] IIT emphasizes the differentiated and integrated aspect of any subjective experience and postulates that the mechanism supporting conscious experience in the human brain’s neocortex must likewise incorporate these two attributes.<p>I don't see any reason why the presumed features of our subjective experience should be "reflected" in the physical working of our brains.
The existence of true unconsciousness is clouded by a seemingly-impenetrable self-reporting problem:<p><i>From the perspective of recall, unconsciousness is indistinguishable from a gap in memory.</i><p>There is no way for a person to determine whether they were truly unconscious or just conscious at a sub-memory level.<p>(This is why I personally doubt the existence of true unconsciousness. I think it’s entirely possible that consciousness is uninterruptible, at least during the lifetime of a conscious organism.)
This is fantastic research about detecting consciousness in the human brain specifically, but I haven't come across much discussion about detecting consciousness <i>in general</i>, in arbitrary arrangements of matter, and by <i>simple inspection</i> (by poking it and seeing how it reacts) Poking it is the traditional way (eg behavioral tests), but that limits detection to only those conscious phenomenon we succeed at poking, and simultaneously succeed at detecting a reaction from (eg it doesn't take 10,000 years to react, or emits chemical pheromone signals that aren't detected/recognized, or communicates via micro-range RF, or something).<p>I call this the "intelligent lifeform sensor" problem, after the implementation from Star Trek.<p>Consciousness is clearly an information theoretical phenomenon that occurs in matter. There should be some sort of general information-theoretical description that applies to matter (be it cephalopods, or rocks, or fungal networks, or exploding stars, or....)