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- Stuart R. Hameroff, Consciousness, Whitehead and Quantum Computation in the Brain: Panprotopsychism Meets the Physics of Fundamental Spacetime Geometry._dualism_ (consciousness lies outside knowable science), _emergence_ (consciousness arises as a novel property from complex computational dynamics in the brain), and some form of _panpsychism_, _pan-protopsychism, or pan-experientialism_ (essential features or precursors of consciousness are fundamental components of reality which are accessed by brain processes). In addition to 1) the problem of subjective experience, other related enigmatic features of consciousness persist, defying technological and philosophical inroads. These include 2) the “binding problem”—how disparate brain activities give rise to a unified sense of “self” or unified conscious content. Temporal synchrony—brain-wide coherence of neural membrane electrical activities—is often assumed to accomplish binding, but _what_ is being synchronized? What is being coherently bound? Another enigmatic feature is 3) the transition from pre-conscious processes to consciousness itself. Most neuroscientists agree that consciousness is the “tip of an iceberg”, that the vast majority of brain activities is.
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Consciousness involves phenomenal experience, self-awareness, feelings, choices, control of actions, a model of the world, etc. But what _is_ _it?_ Is consciousness something specific, or merely a byproduct of information processing? Whatever it is, consciousness is a multi-faceted puzzle. Despite enormous strides in behavioral and brain science, essential features of consciousness continue to elude explanation. Unresolved problems include: 1) Neural correlates of conscious perception apparently occur too late—150 to 500 milliseconds (msec) after impingement on our sense organs—to have causal efficacy in seemingly conscious perceptions and willful actions, often initiated or completed within 100 msec after sensory impingement. For example in the.
Many faces of consciousness -- Ethics, religion, and the identity of self -- States of mind -- Why hearts don't love and brains don't pump -- EEG : a window on the mind -- Dynamic patterns as shadows of thought -- Networks, waves, and resonant binding -- The limits of science : What do we really know? -- Modern physics, cosmology, and consciousness -- The weird behavior of quantum systems -- Ontological interpretations of quantum mechanics -- Does the brain create the mind?
In "Brainshy: Non-neural theories of conscious experience," (this volume) Patricia Churchland considers three "non-neural" approaches to the puzzle of consciousness: 1) Chalmers' fundamental information, 2) Searle's "intrinsic" property of brain, and 3) Penrose-Hameroff quantum phenomena in microtubules. In rejecting these ideas, Churchland flies the flag of "neuralism." She claims that conscious experience will be totally and completely explained by the dynamical complexity of properties at the level of neurons and neural networks. As far as consciousness goes, neural network firing patterns triggered by axon-to-dendrite synaptic chemical transmissions are the fundamental correlates of consciousness. There is no need to look elsewhere.
Consciousness defines our existence and reality. But how does the brain generate thoughts and feelings? Most explanations portray the brain as a computer, with nerve cells ("neurons") and their synaptic connections acting as simple switches, or "bits" which interact in complex ways. In this view consciousness is said to "emerge" as a novel property of complex interactions among neurons, as hurricanes and candle flames emerge from complex interactions among gas and dust molecules. However this approach fails to explain why we have feelings and awareness, an "inner life". So we don't know how the brain produces consciousness.
As an alternative to our original dualistic approach, we present here our spin-mediated consciousness theory based on pan-protopsychism. We postulate that consciousness is intrinsically connected to quantum mechanical spin since said spin is embedded in the microscopic structure of spacetime and may be more fundamental than spacetime itself. Thus, we theorize that consciousness emerges quantum mechanically from the collective dynamics of "protopsychic" spins under the influence of spacetime dynamics. That is, spin is the "pixel" of mind. The unity of mind is achieved by quantum entanglement of the mind-pixels. Applying these ideas to the particular structures and dynamics of the brain, we postulate that the human mind works as follows: The nuclear spin ensembles ("NSE") in both neural membranes and proteins quantum mechanically process consciousness-related information such that conscious experience emerges from the collapses of entangled quantum states of NSE under the influence of the underlying spacetime dynamics. Said information is communicated to NSE through strong spin-spin couplings by biologically available unpaired electronic spins such as those carried by rapidly diffusing oxygen molecules and neural transmitter nitric oxides that extract information from their diffusing pathways in the brain. In turn, the dynamics of NSE has effects through spin chemistry on the classical neural activities such as action potentials and receptor functions thus influencing the classical neural networks of said brain. We also present supporting evidence and make important predictions. We stress that our theory is experimentally verifiable with present technologies.
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Age-old battle lines over the puzzling nature of mental experience are shaping a modern resurgence in the study of consciousness. On one side are the long-dominant "physicalists" who view consciousness as an emergent property of the brain's neural networks. On the alternative, rebellious side are those who see a necessary added ingredient: proto-conscious experience intrinsic to reality, perhaps understandable through modern physics (panpsychists, pan-experientialists, "funda-mentalists"). It is argued here that the physicalist premise alone is unable to solve completely the difficult issues of consciousness and that to do so will require supplemental panpsychist/pan-experiential philosophy expressed in modern physics. In one scheme proto-conscious experience is a basic property of physical reality accessible to a quantum process associated with brain activity. The proposed process is Roger Penrose's "objective reduction" (OR), a self-organizing "collapse" of the quantum wave function related to instability at the most basic level of space-time geometry. In the Penrose- Hameroff model of "orchestrated objective reduction" (Orch OR), OR quantum computation occurs in cytoskeletal microtubules within the brain's neurons. The basic thesis is that consciousness involves brain activities coupled to a self-organizing ripples in fundamental reality.
What is consciousness? Conventional approaches see it as an emergent property of complex interactions among individual neurons; however these approaches fail to address enigmatic features of consciousness. Accordingly, some philosophers have contended that "qualia," or an experiential medium from which consciousness is derived, exists as a fundamental component of reality. Whitehead, for example, described the universe as being composed of "occasions of experience." To examine this possibility scientifically, the very nature of physical reality must be re-examined. We must come to terms with the physics of spacetime-as described by Einstein's general theory of relativity, and its relation to the fundamental theory of matter-as described by quantum theory. Roger Penrose has proposed a new physics of objective reduction: "OR," which appeals to a form of quantum gravity to provide a useful description of fundamental processes at the quantum/classical borderline.hz Within the OR scheme, we consider that consciousness occurs if an appropriately organized system is able to develop and maintain quantum coherent superposition until a specific "objective" criterion (a threshold related to quantum gravity) is reached; the coherent system then self-reduces (objective reduction: OR). We contend that this type of objective self-collapse introduces non-computability, an essential feature of consciousness which distinguishes our minds from classical computers. Each OR is taken as an instantaneous event-the climax of a self-organizing process in fundamental spacetime-and a candidate for a conscious Whitehead "occasion of experience." How could an OR process occur in the brain, be coupled to neural activities, and account for other features of consciousness? We nominate a quantum computational OR process with the requisite characteristics to be occurring in cytoskeletal microtubules within the brain's neurons. In this model, quantum-superposed states develop in microtubule subunit proteins ("tubulins") within certain brain neurons, remain coherent, and recruit more superposed tubulins until a mass-time-energy threshold (related to quantum gravity) is reached..
Discussion of Stuart R. Hameroff, Consciousness, Whitehead and quantum computation in the brain: Panprotopsychism meets the physics of fundamental spacetime geometry
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