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Consciousness May Be the Product of Carefully Balanced Chaos (sciencemag.org)
sciencehabit writes: The question of whether the human consciousness is subjective or objective is largely philosophical. But the line between consciousness and unconsciousness is a bit easier to measure. In a new study (abstract) of how anesthetic drugs affect the brain, researchers suggest that our experience of reality is the product of a delicate balance of connectivity between neurons—too much or too little and consciousness slips away. During wakeful consciousness, participants’ brains generated “a flurry of ever-changing activity”, and the fMRI showed a multitude of overlapping networks activating as the brain integrated its surroundings and generated a moment to moment “flow of consciousness.” After the propofol kicked in, brain networks had reduced connectivity and much less variability over time. The brain seemed to be stuck in a rut—using the same pathways over and over again.
Correct, but missing the point.
To clarify: remember that chaotic does not mean unbounded nor non-deterministic, just that the state becomes more and more dependent on the initial/boundary conditions as time passes. So to predict the state at time t0 you might need to know initial conditions to say 20 decimal places, but to predict at time t1>>t0 you might need to know initial conditions at say 500 decimal places, and so on, making the output deterministic in theory but unpredictable in practice (though you sometimes might see things like emergent cyclic behaviour, attractors etc). The state *may* be unbounded ("output" becoming bigger and bigger over time) and chaotic at the same time, but it can also be both bounded and chaotic - google the logistic map for example.
Back to the article, what they are arguing is that if you have too much connectivity (and yes there are loops, so it is feedback) things just go haywire - like the feedback you get when you put your mic in front of the speaker - and you get things like epilepsy. Too little connectivity (and hence feedback) and things converge to something like a steady state (simplifying obviously, but not overly) - aka anaesthetised/asleep/in coma. Get the level of connectivity/feedback just right and you have a system that is both chaotic and bounded. Unpredictable in practice, but not just randomly shooting off in any old direction as per the over-connected case. And that is where the interesting stuff happens.
Not actually a new idea, but still an interesting one.