A central issue of cognitive neuroscience is to understand how a large collection of coupled neurons combines external signals with internal memories into new coherent patterns of meaning. An external stimulus localized at some input spreads over a large assembly of coupled neurons, building up a collective state univocally corresponding to the stimulus. Thus, the synchronization of spike trains of many individual neurons is the basis of a coherent perception. Based on recent investigations of homoclinic chaotic systems and their synchronization, (...) a novel conjecture for the dynamics of single neurons and, consequently, for neuron assemblies is formulated. Homoclinic chaos is proposed as a suitable way to code information in time by trains of equal spikes occurring at apparently erratic times. In order to classify the set of different perceptions, the percept space can be given a metric structure by introducing a distance measure between distinct percepts. The distance in percept space is conjugate to the duration of the perception in the sense that an uncertainty relation in percept space is associated with time-limited perceptions. This coding of different percepts by synchronized spike trains entails fundamental quantum features which are not restricted to microscopic phenomena. It is conjectured that they are related to the details of the perceptual chain rather than depending on Planck's action. (shrink)

It is widely accepted that consciousness or, more generally, mental activity is in some way correlated to the behavior of the material brain. Since quantum theory is the most fundamental theory of matter that is currently available, it is a legitimate question to ask whether quantum theory can help us to understand consciousness. Several approaches answering this question affirmatively, proposed in recent decades, will be surveyed. It will be pointed out that they make different epistemological assumptions, refer to different neurophysiological (...) levels of description, and use quantum theory in different ways. For each of the approaches discussed, problematic and promising features will be equally highlighted. (shrink)

It is widely accepted that consciousness or, in other words, mental activity is in some way correlated to the behavior of the brain or, in other words, material brain activity. Since quantum theory is the most fundamental theory of matter that is currently available, it is a legitimate question to ask whether quantum theory can help us to understand consciousness. Several approaches answering this question a?rmatively, proposed in recent decades, will be surveyed. It will be pointed out that they make (...) di?erent epistemological assumptions, refer to di?erent neurophysiological levels of description, and adopt quantum theory in di?erent ways. For each of the approaches discussed, these imply both.. (shrink)

This book will undoubtedly be useful to scholars and graduate students interested in the relationships between self-consciousness, emotion, the brain, and the...

I discuss the quantum mechanical theory of consciousness and freewill offered by Stapp (1993, 1995, 2000, 2004). First I show that decoherence-based arguments do not work against this theory. Then discuss a number of problems with the theory: Stapp's separate accounts of consciousness and freewill are incompatible, the interpretations of QM they are tied to are questionable, the Zeno effect could not enable freewill as he suggests because weakness of will would then be ubiquitous, and the holism of measurement in (...) QM is not a good explanation of the unity of consciousness for essentially the same reason that local interactions may seem incapable to account for it. (shrink)

I argue that a dual-aspect theory of consciousness, associated with a particular class of quantum states, can provide a consistent account of consciousness. I illustrate this with the use of coherent states as this class. The proposal meets Chalmers 'requirements of allowing a structural correspondence between consciousness and its physical correlate. It provides a means for consciousness to have an effect on the world (it is not an epiphenomenon, and can thus be selected by evolution) in a way that supplements (...) and completes conventional physics, rather than interfering with it. I draw on the work of Hameroff and Penrose to explain the consistency of this proposal with decoherence, while adding details to this work. The proposal is open to extensive further research at both theoretical and experimental levels. (shrink)

This Whiteheadian Dialogue explores a fresh and important cross-elucidatory path: What have we, and what can be learned from a dialogue with Eastern worldviews?

We show that consciousness may violate the basic quantum principle, according to which the nonorthogonal quantum states can't be distinguished. This implies that the physical world is not causally closed without consciousness, and consciousness is a fundamental property of matter.

CHAPTER Heidegger and the Quantum Brain In any case the orientation to "I" and " consciousness" and re-presentation ...

Using the Gödel Incompleteness Result for leverage, Roger Penrose has argued that the mechanism for consciousness involves quantum gravitational phenomena, acting through microtubules in neurons. We show that this hypothesis is implausible. First, the Gödel Result does not imply that human thought is in fact non algorithmic. Second, whether or not non algorithmic quantum gravitational phenomena actually exist, and if they did how that could conceivably implicate microtubules, and if microtubules were involved, how that could conceivably implicate consciousness, is entirely (...) speculative. Third, cytoplasmic ions such as calcium and sodium are almost certainly present in the microtubule pore, barring the quantum mechanical effects Penrose envisages. Finally, physiological evidence indicates that consciousness does not directly depend on microtubule properties in any case, rendering doubtful any theory according to which consciousness is generated in the microtubules. (shrink)

_Figure 1. Dendrites and cell bodies of schematic neurons connected by dendritic-dendritic gap junctions form a laterally connected input_ _layer (“dendritic web”) within a neurocomputational architecture. Dendritic web dynamics are temporally coupled to gamma synchrony_ _EEG, and correspond with integration phases of “integrate and fire” cycles. Axonal firings provide input to, and output from, integration_ _phases (only one input, and three output axons are shown). Cell bodies/soma contain nuclei shown as black circles; microtubule networks_ _pervade the cytoplasm. According to the (...) Orch OR theory, gamma EEG-synchronized integration phases include quantum computations in_ _microtubule networks which culminate with conscious moments. Insert closeup shows a gap junction through which microtubule quantum_ _states entangle among different neurons, enabling macroscopic quantum states in dendritic webs extending throughout cortex and other_ _brain regions._. (shrink)

_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. (shrink)

Proposals for quantum computation rely on superposed states implementing multiple computations simultaneously, in parallel, according to quantum linear superposition (e.g., Benioff, 1982; Feynman, 1986; Deutsch, 1985, Deutsch and Josza, 1992). In principle, quantum computation is capable of specific applications beyond the reach of classical computing (e.g., Shor, 1994). A number of technological systems aimed at realizing these proposals have been suggested and are being evaluated as possible substrates for quantum computers (e.g. trapped ions, electron spins, quantum dots, nuclear spins, etc., (...) see Table 1; Bennett, 1995; and Barenco, 1995). The main obstacle to realization of quantum computation is the problem of interfacing to the system (input, output) while also protecting the quantum state from environmental decoherence. If this problem can be overcome, then present day classical computers may evolve to quantum computers. (shrink)

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.. (shrink)

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. (shrink)

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. (shrink)

_Sonoran Desert, Stuart Hameroff and Alwyn Scott awoke from their_ _siestas to take margaritas in the shade of a ramada. On a nearby_ _table, a tape recorder had accidentally been left on and the following_ _is an unedited transcript of their conversation._.

A structural analogy is pointed out between a check hermeneutically developed phenomenological description, based on Husserl, of the process of perceptual cognition on the one hand and quantum mechanical measurement on the other hand. In Husserl's analytic phase of the cognition process, the 'intentionality-structure' of the subject/object union prior to predication of a local object is an entangled symmetry-making state, and this entanglement is broken in the synthetic phase when the particular local object is constituted under the influence of an (...) iota ('inner horizon') and the 'facticity' of the local world ('outer horizon'). Replacing 'perceptual cognition' by 'measurement' and 'subject' by 'expert subject using a measuring device' the analogy of a formal quantum structure is extended to the conscious structure of all empirical cognition. This is laid out in three theses: about perception, about classical measurement, and about quantum measurement. The results point to the need for research into the quantum structure of the physical embodiment of human cognition. (shrink)

Mainstream cognitive neuroscience typically ignores the role of quantum physical effects in the neural processes underlying cogni¬tion and consciousness. However, many unsolved problems remain, suggesting the need to consider new approaches. We propose that quantum theory, especially through an ontological interpretation due to Bohm and Hiley, provides a fruitful framework for addressing the neural correlates of cognition and consciousness. In particular, the ontological interpretation suggests that a novel type of 'active information', connected with a novel type of 'quantum potential energy', (...) plays a key role in quantum physical processes. After introducing the ontological interpretation we illustrate its value for cognitive neuroscience by discussing it in the light of a proposal by Beck and Eccles about how quantum tunneling could play a role in controlling the frequency of synaptic exocytosis. In this proposal, quantum tunneling would enable the 'self' to control its brain without violating the energy conservation law. We argue that the ontological interpretation provides a sharper picture of what actually could be taking place in quantum tunneling in general and in synaptic exocytosis in particular. Based on the notions of active information and quantum potential energy, we propose a coherent way of understanding how mental processes (understood as involving non-classical physical processes) can act on traditional, classically describable neural processes without violating the energy conservation law. (shrink)

The book is the first to give a systematic account, founded in fundamental quantum physical principles, of how the brain functions as a unified system.

This comprehensive reference provides an exhaustive guide to current scholarship on the perennial problem of Free Will--perhaps the most hotly and voluminously debated of all philosophical problems. While reference is made throughout to the contributions of major thinkers of the past, the emphasis is on recent research. The essays, most of which are previously unpublished, combine the work of established scholars with younger thinkers who are beginning to make significant contributions. Taken as a whole, the Handbook provides an engaging and (...) accessible roadmap to the state of the art thinking on this enduring topic. (shrink)

These views on the nature of consciousness are briefly discussed. The first view to be considered is the most widespread functionalist version of the ...

I argue that the logical difference between classical and quantum mechanics that Stapp (1995) claims shows quantum mechanics is more amenable to an account of consciousness than is classical mechanics is irrelevant to the problem.

We contrast person-centered categories with objective categories related to physics: consciousness vs. mechanism, observer vs. observed, agency vs. event causation. semantics vs. syntax, beliefs and desires vs. dispositions. How are these two sets of categories related? This talk will discuss just one such dichotomy: consciousness vs. mechanism. Two extreme views are dualism and reductionism. An intermediate view is emergence. Here, consciousness is part of the natural order (as against dualism), but consciousness is not definable only in terms of physical mass, (...) length, and time (as against reductionism). There are several detailed theories of emergence. One is based on the Great Chain of Being and on organic evolutionary hierarchy. The theory here is based instead on the concept of relational holism in quantum mechanics. The resulting brain model has two interacting systems: a computational system and a quantum system (a Bose-Einstein condensate), perhaps interacting via EEG waves. Thus, we need both person-centered and matter-centered categories to describe human beings. Some possible experimental tests are discussed. (shrink)

Features of consciousness difficult to understand in terms of conventional neuroscience have evoked application of quantum theory, which describes the fundamental behavior of matter and energy. In this paper we propose that aspects of quantum theory (e.g. quantum coherence) and of a newly proposed physical phenomenon of quantum wave function "self-collapse"(objective reduction: OR -Penrose, 1994) are essential for consciousness, and occur in cytoskeletal microtubules and other structures within each of the brain's neurons. The particular characteristics of microtubules suitable for quantum (...) effects include their crystal-like lattice structure, hollow inner core, organization of cell function and capacity for information processing. We envisage that conformational states of microtubule subunits (tubulins) are coupled to internal quantum events, and cooperatively interact (compute) with other tubulins. We further assume that macroscopic coherent superposition of quantum-coupled tubulin conformational states occurs throughout significant brain volumes and provides the global binding essential to consciousness. We equate the emergence of the microtubule quantum coherence with pre-conscious processing which grows (for up to 500 milliseconds) until the mass-energy difference among the separated states of tubulins reaches a threshold related to quantum gravity. According to the arguments for OR put forth in Penrose (1994), superpositioned states each have their own space-time geometries. When the degree of coherent mass-energy difference leads to sufficient separation of space-time geometry, the system must choose and decay (reduce, collapse) to a single universe state. In this way, a transient superposition of slightly differing space-time geometries persists until an abrupt quantum classical reduction occurs. Unlike the random, "subjective reduction"( SR, or R) of standard quantum theory caused by observation or environmental entanglement, the OR we propose in microtubules is a self-collapse and it results in particular patterns of microtubule-tubulin conformational states that regulate neuronal activities including synaptic functions. (shrink)

Grush and Churchland (1995) attempt to address aspects of the proposal that we have been making concerning a possible physical mechanism underlying the phenomenon of consciousness. Unfortunately, they employ arguments that are highly misleading and, in some important respects, factually incorrect. Their article ‘Gaps in Penrose’s Toilings’ is addressed specifically at the writings of one of us (Penrose), but since the particular model they attack is one put forward by both of us (Hameroff and Penrose, 1995; 1996), it is appropriate (...) that we both reply; but since our individual remarks refer to different aspects of their criticism we are commenting on their article separately. The logical arguments discussed by Grush and Churchland, and the related physics are answered in Part l by Penrose, largely by pointing out precisely where these arguments have already been treated in detail in Shadows of the Mind (Penrose, 1994). In Part 2, Hameroff replies to various points on the biological side, showing for example how they have seriously misunderstood what they refer to as ‘physiological evidence’ regarding to effects of the drug colchicine. The reply serves also to discuss aspects of our model ‘orchestrated objective reduction in brain microtubules – Orch OR’ which attempts to deal with the serious problems of consciousness more directly and completely than any previous theory. (shrink)

We review the dissipative quantum model of the brain and present recent developments related to the role of entanglement, quantum noise and chaos in the model.

We study the possible connection between self-consciousness and quantum process. It is shown that the self-consciousness function can help to measure the collapse time of wave function under some condition, while the usual physical device without self-consciousness can't. Furthermore, we show that the observer with self-consciousness can distinguish the definite state and the superposition of definite states under some stronger condition. This provides a practical physical method to differentiate man and machine, and will also help to find the possible existence (...) of self-consciousness in the animal kingdom. We finally give some further discussions about these new results. (shrink)

Classical physics is a theory of nature that originated with the work of Isaac Newton in the seventeenth century and was advanced by the contributions of James Clerk Maxwell and Albert Einstein. Newton based his theory on the work of Johannes Kepler, who found that the planets appeared to move in accordance with a simple mathematical law, and in ways wholly determined by their spatial relationships to other objects. Those motions were apparently independent of our human observations of them.

b>: Replacing faulty nineteenth century physics by its orthodox quantum successor converts the earlier materialist conception of nature to a structure that does not enforce the principle of the causal closure of the physical. The quantum laws possess causal gaps, and these gaps are filled in actual scientific practice by inputs from our streams of consciousness. The form of the quantum laws permits and suggests the existence of an underlying reality that is built not on substances, but on psychophysical events, (...) and on objective tendencies for these events to occur. These events constitute intrinsic mind-brain connections. They are fundamental links between brain processes described in physical terms and events in our streams of consciousness. This quantum ontology confers upon our conscious intentions the causal efficacy assigned to them in actual scientific practice, and creates a substance- free interactive dualism. This putative quantum ontology has previously been shown to have impressive explanatory power in both psychology and neuroscience. Here it is used to reconcile the existence of physically efficacious conscious free will with causal anomalies of both the Libet and Einstein-Rosen-Podolsky types. (shrink)

_ Theoretical Physics Group_ _ Lawrence Berkeley National Laboratory_ _ University of California_ _ Berkeley, California 94720_.

Quantum approaches to consciousness are sometimes said to be motivated simply by the idea that quantum theory is a mystery and consciousness is a mystery, so perhaps the two are related. That opinion betrays a profound misunderstanding of the nature of quantum mechanics, which consists fundamentally of a pragmatic scientific solution to the problem of the connection between mind and matter.

Neuropsychological research on the neural basis of behaviour generally posits that brain mechanisms will ultimately suffice to explain all psychologically described phenomena. This assumption stems from the idea that the brain is made up entirely of material particles and fields, and that all causal mechanisms relevant to neuroscience can therefore be formulated solely in terms of properties of these elements. Thus, terms having intrinsic mentalistic and/or experiential content (e.g. ‘feeling’, ‘knowing’ and ‘effort’) are not included as primary causal factors. This (...) theoretical restriction is motivated primarily by ideas about the natural world that have been known to be fundamentally incorrect for more than three-quarters of a century. Contemporary basic physical theory differs profoundly from classic physics on the important matter of how the consciousness of human agents enters into the structure of empirical phenomena. The new principles contradict the older idea that local mechanical processes alone can account for the structure of all observed empirical data. Contemporary physical theory brings directly and irreducibly into the overall causal structure certain psychologically described choices made by human agents about how they will act. This key development in basic physical theory is applicable to neuroscience, and it provides neuroscientists and psychologists with an alternative conceptual framework for describing neural processes. Indeed, owing to certain structural features of ion channels critical to synaptic function, contemporary physical theory must in principle be used when analysing human brain dynamics. The new framework, unlike its classic-physics-based predecessor, is erected directly upon, and is compatible with, the prevailing principles of physics. It is able to represent more adequately than classic concepts the neuroplastic mechanisms relevant to the growing number of empirical studies of the capacity of directed attention and mental effort to systematically alter brain function.. (shrink)

David Bourget has raised some conceptual and technical objections to my development of von Neumann’s treatment of the Copenhagen idea that the purely physical process described by the Schrödinger equation must be supplemented by a psychophysical process called the choice of the experiment by Bohr and Process 1 by von Neumann. I answer here each of Bourget’s objections.

Replies are given to arguments advanced in this journal that claim to show that it is to nonlinear classical mechanics rather than quantum mechanics that one must look for the physical underpinnings of conscious ness..

Quantum theory can be regarded as a rationally coherent theory of the interaction of mind and matter and it allows our conscious thoughts to play a causally e cacious and necessary role in brain dynamics It therefore provides a natural basis created by scientists for the science of consciousness As an illustration it is explained how the interaction of brain and consciousness can speed up brain processing and thereby enhance the survival prospects of conscious organisms as compared to similar organisms (...) that lack consciousness As a second illustration it is explained how within the quantum framework the consciously experi enced I directs the actions of a human being It is concluded that contemporary science already has an adequate framework for incorporat ing causally e cacious experiential events into the physical universe in a manner that puts the neural correlates of consciousness into the theory in a well de ned way explains in principle how the e ects of consciousness per se can enhance the survival prospects of organisms that possess it allows this survival e ect to feed into phylogenetic de velopment and explains how the consciously experienced I can direct human behaviour.. (shrink)

Quantum mechanics unites epistemology and ontology: it brings human knowledge explicitly into physical theory, and ties this knowledge into brain dynamics in a causally efficacious way. This development in science provides the basis for a natural resolution of the dualist functionalist controversy, which arises within the classical approach to the mind brain system from the fact that the phenomenal aspects are not derivable from the principles of classical mechanics. A conceptually simple causal quantum mechanical theory of the mind/brain is described, (...) and used to examine the necessity and function of consciousness in brain process. (shrink)

This document was prepared as an account of work sponsored by the United States Government. While this document is believed to contain correct information, neither the United States Government nor any agency thereof, nor The Regents of the University of California, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe (...) privately owned rights. Reference herein to any speci c commercial products process, or service by its trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof, or The Regents of the University of California. The views and opinions of authorsexpressed herein do not necessarily state or re ect those of the United States Government or.. (shrink)

Physics Department, University of Surrey, Guildford GU2 5XH, U.K October, 1990. We may suspect that quantum mechanics and consciousness are related, but the details are not at all clear. In this paper, I suggest how the mind and brain might fit together intimately while still maintaining distinct identities. The connection is based on the correspondence of similar functions in both the mind and the quantum-mechanical brain. Accompanying material for a talk at The Second Mind and Brain Symposium held at the (...) Institute of Psychiatry, Denmark Hill, London on 20th October, 1990. (shrink)