The well known philosopher of mind, Jerry Foder, famously quipped that, "Not only have we no idea what conscious 'is,' we have no idea what it would be like to have an idea what consciousness 'is.'"
To my considerable surprise, I do have an idea what consciousness may be, and how to begin to test for it.
In the last blog, following Alfred North Whitehead, who thought in terms of Actuals giving rise to Possibles giving rise to Actual, and W. Heisenberg, among the giant founders of Quantum Mechanics, with a similar view, I proposed a testable hypothesis of a new dualism, the realm of the Possible, Res Potentia, and the realm of the Actual, Res Extensa. Res Potentia and Res Extensa really are linked by quantum measurement. In von Neumann's axiomatization of Quantum Mechanics, this is his R process, the "collapse of the wave function".
I quote Shimon Malin, a quantum field theorist, from "Physics and Whitehead" (Ed. T.E. Eastman and H. Keaton). "According to Heisenberg, the interplay between the two modes of quantum systems, being isolated and being measured, is an interplay between potentialities and actualities."
Quoting Malin again, "Heisenberg's interpretation implies that the collapse of a quantum state is not a process in time."
Heisenberg's view supports a "strong" version of Res Potentia and Res Extensa linked by Measurement, the former, bearing on the unitary propagation of the Schrodinger equation in Res Potentia, before measurement, and evading Aristotle's Law of the Excluded Middle, the latter, bearing on classical physics and entirely bound by the Law of the Excluded Middle. On the strong version of the dualism, Res Potentia and Res Extensia, we will NOT deduce measurement from within quantum mechanics. As Malin says, on Heisenberg, collapse is not a process in time.
I adopt Res Potentia and Res Extensia linked by Measurement, both ontologically real, as a working hypothesis, which may be true or false.
Then: What IS consciousness? The obvious hypothesis is that mind and consciousness participate in Res Potentia. Mind participates in an ontologically real Possible.
I offer two pieces of evidence.
1) Where is the possibility that I will skate across town reading the NY Times and not be hit by any cars, on my way to buy groceries? I think we all feel that possibilities are not spatially locatable, that is, not spatially extended.
2) Now consider your experienced visual field. Where is your experienced field located? I think we all sense that our experience itself is not located spatially, that is, it is not spatially extended.
This non-spatial character of both "Possibilities" and Experience may be happenstance, or a clue. Taking this parallel as a clue may lead us forward in new ways.
Where is it natural to locate experience, or qualia? I hypothesis that experience, qualia, the experience of the blueness of blue, is associated with quantum measurement. I note that R. Penrose and H. Stapp, respectively a mathematician and a quantum physicist, have made the same suggestion before me.
On this view unconscious mind or dreamless sleep may well be related to Res Potenia. But our conscious experience itself is associated only with measurement. If measurement is not a substance and not process in time, we cannot pick up a shovel-full of experience.
In a later post I will hypothesize that quantum entanglement and non-local measured quantum correlations may play a role in the Unity of Consciousness and the very short term "iconic memory" needed for conscious experience.
And I will suggest that the loci of such measurements and entanglements may well be synapses.
I note that an association of qualia with measurement does not, as yet, tell us what qualia are.
However, as David Chalmers notes in his book, The Conscious Mind, we want to understand why we hear a bell "ring", but see a color "red". Why do these differences in qualia exist in our experience? A testable possibility is that the different character of qualia are associated with the different rich correlations yielded by measurements of quantum entangled degrees of freedom among different sets of synapses or degrees of freedom within synapses. Were we to find such correlations, we would still not know what qualia ARE, but at least could have established that they are correlated with measurements of entangled quantum degrees of freedom, perhaps in synapses.
There are real clues to the brain loci of the measurement events I hypothesize are associated with conscious experience. Anesthetics are known in a number of cases to bind to hydrophobic pockets in the post synaptic protein receptors for the neurotransmitters acetylcholine, serotonin, and GABA. These neurotransmitters are released from vesicles on the presynaptic side of the synaptic cleft and diffuse beyond the cleft and bind to their cognate post synaptic receptors. The bound receptors act on the post synaptic dendrites to alter their membrane potentials. In turn these alterations are summed at the nerve cell's axon hillock and, if above a threshold, yield an action potential spike in the axon of the downstream neuron.
If quantum measurement is necessary for experiencing qualia, then anesthetics may act by "freezing" post synaptic neurotransmitter receptors, perhaps in the post-synaptic membrane, into a stable "classical" state, such that they can no longer undergo measurement from quantum to classical, from Res Potentia to Res Extensa. Then experiences, qualia, cannot arise and we are anesthetized.
This hypothesis is testable. We can test if chlorophyll is quantum coherent or not, so we can test if anesthetics block quantum coherence in post synaptic neurotransmitter receptors. If found, such results would be a first step in testing the hypothesis that qualia are associated with quantum measurement.
If dreamless sleep or unconscious mental activity is unmeasured open quantum or Poised Realm behavior, this too may be testable.
Even were such experiments successful, and even were we be convinced that qualia are indeed associated with measurement events in the brain, there is a very long way to go to integrate such an insight into the many decades of detailed psychological experiments on consciousness and the details of neural network architecture, dynamical behaviors and the roles of those behaviors in conscious experiences, well summarized in Francis Crick's "The Astonishing Hypothesis". In a future post, Standing The Brain On Its Head, I will suggest the testable idea that the wondrous neurophysiology of the brain serves to deliver extremely fine grained spatial and temporal alterations in different tiny local transmembrane potentials in synapses and dendritic arborizations which modulate local synaptic measurement events. Rather than a "neural code" of time varying action potential spike trains, I think we may want also to consider finely modulated synaptic behaviors as the brain "code" for consciousness.