the frontiers collection the frontiers collection Series Editors: A.C. Elitzur M.P. Silverman J. Tuszynski R. Vaas H.D. Zeh The books in this collection are devoted to challenging and open problems at the forefront of modern science, including related philosophical debates. In contrast to typical research monographs, however, they strive to present their topics in a manner accessible also to scientifically literate non-specialists wishing to gain insight into the deeper implications and fascinating questions involved. Taken as a whole, the series reflects the need for a fundamental and interdisciplinary approach to modern science. Furthermore, it is intended to encourage active scientists in all areas to ponder over important and perhaps controversial issues beyond their own speciality. Extending from quantum physics and relativity to entropy, consciousness and complex systems – the Frontiers Collection will inspire readers to push back the frontiers of their own knowledge. Information and Its Role in Nature Mind, Matter and QuantumMechanics By J. G. Roederer By H. Stapp Relativity and the Nature of Spacetime QuantumMechanics and Gravity By V. Petkov By M. Sachs Quo Vadis QuantumMechanics? Extreme Events in Nature and Society Edited by A. C. Elitzur, S. Dolev, Edited by S. Albeverio, V. Jentsch, N. Kolenda H. Kantz Life – As aMatter of Fat The Thermodynamic The Emerging Science of Lipidomics Machinery of Life By O.G. Mouritsen By M. Kurzynski Quantum–Classical Analogies The Emerging Physics By D. Dragoman and M. Dragoman of Consciousness Edited by J. A. Tuszynski Knowledge and the World Challenges Beyond the Science Wars Weak Links Edited by M. Carrier, J. Roggenhofer, Stabilizers of Complex Systems G. Küppers, P. Blanchard from Proteins to Social Networks By P. Csermely Quantum–Classical Correspondence By A.O. Bolivar Jack A. Tuszynski (Ed.) THE EMERGING PHYSICS OF CONSCIOUSNESS With 135 Figures and 10 Tables 123 Prof. Jack A. Tuszynski University of Alberta Department of Physics T6G 2J1 Edmonton, AB Canada e-mail: Preface Consciousness, once a topic alluded to only by philosophers and, occasionally, theologians, has – in the past 20 years or so – migrated into the domain of science and rational analysis. But this does not mean to say that conscious experience is now understood in the way that we understand other phenom- ena once attributed to otherworldly causes – earthquakes or solar eclipses, for example. On the contrary, consciousness remains one of the major unsolved problems in science. But science and scientists are gradually becoming able and willing to tackle this phenomenon, to ask pertinent questions, and to use the newly available technology to carry out decisive experiments. Some of the questions that are now being addressed, and which will fea- ture in this volume are: How do the feelings and sensations making up con- scious experience arise from the concerted actions of nerve cells and their associated synaptic and molecular processes? How do the operations of the conscious mind emerge out of the specific interactions involving billions of neurons? What physical mechanisms and brain processes lie behind partic- ular conscious experiences? And how can this vital information be collected experimentally? Can conscious awareness really be explained by modern sci- ence, or is an entirely different kind of explanation needed after all? This multi-authored book seeks answers to these questions within a range of physically based frameworks. Thus, the underlying assumption is that consciousness can indeed be understood using the intellectual potential of modern physics and other sciences. There are a number of theories of con- sciousness in existence, some based on classical physics, whilst others require the use of quantum concepts. The latter have drawn criticism from parts of the scientific establishment, while simultaneously claiming that classical ap- proaches are doomed to failure. This book presents a spectrum of opinions, models and theories as well as some experimental evidence to elucidate the various approaches within this on-going scientific debate. It will enable read- ers to decide for themselves which hypotheses and which directions of study appear most promising. We have solicited contributions from a number of eminent scientists in the field, some very original thinkers, several well-known science writers and free thinkers. In their attempts to identify and understand the roots of con- sciousness, the authors variously exploit experimental, theoretical and even philosophical approaches. The volume begins with a general overview writ- ten jointly by Nancy Woolf and Jack Tuszynski. This includes, in Sect. 1.2, a detailed synopsis of the further contributions, together with a few words about the ‘allegiances’ of their authors in the ongoing debate. We believe that this book will help to set the scene for future explorations in this field by new generations of scientists. At the least, it would be gratify- ing if this volume were to inspire many of its readers think about the concept of consciousness as a journey of scientific discovery. We hope the reader will enjoy these essays as much as the editorial team did. Edmonton, Canada March 2006 Jack Tuzsynski Contents 1 The Path Ahead Jack A. Tuszynski, Nancy Woolf . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.1 Definition and Fundamentals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.1.1 Definition of Consciousness and the Classical Approach . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1.2 Quantum Theories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.1.3 Quantum Processing by Microtubules and Neurocognition . . . . . . . . . . . . . . . . . . 8 1.2 Overview of the Contributions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 1.3 New and Notable Developments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 1.3.1 An Electromagnetic Fingerprint of Transport Along Microtubules . . . . . . . . . . . . . . . . . . . . . 17 1.3.2 Extrapolations to Mesoscopic and Macroscopic Levels . . . 22 1.4 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 2 Consciousness and Quantum Physics: Empirical Research on the Subjective Reduction of the Statevector Dick J. Bierman, Stephen Whitmarsh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 2.1.1 The Measurement Problem . . . . . . . . . . . . . . . . . . . . . . . . . . 27 2.1.2 Objective Reduction and Consciousness . . . . . . . . . . . . . . . 29 2.1.3 Previous Empirical Work on Subjective Reduction . . . . . . 30 2.1.4 Current Investigation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 2.2 Experimental Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 2.3 Experimental Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 2.3.1 Subjects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 2.3.2 Physiological Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . 36 2.3.3 Further Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 2.4 Data Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 2.5 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 2.6 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 2.7 Further Research . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 VI Contents 3 Microtubules in the Cerebral Cortex: Role in Memory and Consciousness Nancy J. Woolf . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 3.1.1 General Features of the Brain . . . . . . . . . . . . . . . . . . . . . . . . 49 3.1.2 Neuronal Assemblies: Patterns of Connection . . . . . . . . . . 51 3.1.3 Neurons, Synapses and Neurotransmitter Molecules . . . . . 52 3.2 Functions of Microtubules and MAPs . . . . . . . . . . . . . . . . . . . . . . . . 56 3.2.1 Transport along Microtubules . . . . . . . . . . . . . . . . . . . . . . . . 57 3.2.2 Signal Transduction and Anchoring of Signal-Transduction Molecules . . . . . . . . . . . . . . . . . . . . . 57 3.3 Learning and Memory: Neuroplasticity vs. Stability . . . . . . . . . . . . 65 3.3.1 Synaptic Change: Hebb’s Rule Revisited . . . . . . . . . . . . . . 66 3.3.2 Microtubules and MAPs in Dendrites Play a Critical Role in Memory . . . . . . . . . . . . . . . . . . . . . . 70 3.3.3 Microtubules Influence Synaptic Efficacy . . . . . . . . . . . . . . 77 3.4 Consciousness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 3.4.1 Attention: The Spotlight of Consciousness . . . . . . . . . . . . . 78 3.4.2 Waking, Sleeping and Dreaming: Different Levels of Consciousness . . . . . . . . . . . . . . . . . . . . . 80 3.4.3 Mental Force to Think and Act . . . . . . . . . . . . . . . . . . . . . . 81 3.4.4 Consciousness, Memory and Microtubules . . . . . . . . . . . . . 83 3.5 Microtubules and Quantum Entanglement: A Possible Basis for Memory and Consciousness . . . . . . . . . . . . . . . 85 3.6 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 4 Towards Experimental Tests of Quantum Effects in Cytoskeletal Proteins Andreas Mershin, Hugo Sanabria, John H. Miller, Dharmakeerthna Nawarathna, Efthimios M.C. Skoulakis, Nikolaos E. Mavromatos, Alexadre A. Kolomenskii, Hans A. Schuessler, Richard F. Luduena, Dimitri V. Nanopoulos . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 4.1.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 4.1.2 Tubulin and Microtubules . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 4.1.3 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 4.2 QED Model of Tubulin and its Implications . . . . . . . . . . . . . . . . . . . 102 4.2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102 4.2.2 Quantum Coherence in Biological Matter? . . . . . . . . . . . . . 105 4.2.3 Implications for Cell Function . . . . . . . . . . . . . . . . . . . . . . . . 115 4.2.4 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120 4.3 Tau Accumulation in Drosophila Mushroom Body Neurons Results in Memory Impairment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120 4.3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120 Contents VII 4.3.2 Drosophila . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121 4.3.3 Genetic Engineering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123 4.3.4 Conditioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126 4.3.5 Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128 4.3.6 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132 4.3.7 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134 4.3.8 Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134 4.4 Refractometry, Surface Plasmon Resonance, and Dielectric Spectroscopy of Tubulin and Microtubules . . . . . . . . . . . . . . . . . . . . 136 4.4.1 Theory of Dielectrics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136 4.4.2 Optics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 4.4.3 Surface Plasmon Resonance (SPR) . . . . . . . . . . . . . . . . . . . 145 4.4.4 Dielectric Spectroscopy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153 4.5 Emerging Directions of Experimental Tests of the Quantum Consciousness Idea . . . . . . . . . . . . . . . . . . . . . . . . . . 159 4.5.1 Entanglement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159 4.5.2 Molecular Electronics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160 4.5.3 Proposed Further Research . . . . . . . . . . . . . . . . . . . . . . . . . . 160 4.6 Unification of Concepts and Conclusions . . . . . . . . . . . . . . . . . . . . . 163 4.6.1 Putting It All Together . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163 4.6.2 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 5 Physicalism, Chaos and Reductionism Alwyn Scott . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171 5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171 5.2 Quantum and Classical Dynamics . . . . . . . . . . . . . . . . . . . . . . . . . . . 172 5.3 What Are Classical Nonlinear Phenomena? . . . . . . . . . . . . . . . . . . . 173 5.4 The Biological and Cognitive Hierarchies . . . . . . . . . . . . . . . . . . . . . 174 5.5 Reductionism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177 5.6 Objections to Reductionism. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179 5.6.1 Constructionism versus Reductionism . . . . . . . . . . . . . . . . . 179 5.6.2 Immense Numbers of Possibilities . . . . . . . . . . . . . . . . . . . . 180 5.6.3 Sensitive Dependence on Initial Conditions . . . . . . . . . . . . 181 5.6.4 The Nature of Causality . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181 5.6.5 Nonlinear Causality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183 5.6.6 The Nature of Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184 5.6.7 Downward Causation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184 5.6.8 Open Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185 5.6.9 Closed Causal Loops . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186 5.7 Concluding Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190 VIII Contents 6 Consciousness, Neurobiology and Quantum Mechanics: The Case for a Connection Stuart Hameroff . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193 6.1 Introduction: The Problems of Consciousness . . . . . . . . . . . . . . . . . 193 6.2 Time and Consciousness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197 6.2.1 Is Consciousness Continuous or a Sequence of Discrete Events? . . . . . . . . . . . . . . . . . . . . 197 6.2.2 The Timing of Conscious Experience . . . . . . . . . . . . . . . . . 198 6.2.3 Taking Backward Time Referral Seriously . . . . . . . . . . . . . 202 6.3 The Neural Correlate of Consciousness . . . . . . . . . . . . . . . . . . . . . . . 206 6.3.1 Functional Organization of the Brain . . . . . . . . . . . . . . . . . 206 6.3.2 Cerebral Cortex and Neuronal Assemblies . . . . . . . . . . . . . 208 6.3.3 Axons and Dendrites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208 6.3.4 Neural Synchrony . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212 6.3.5 Gap-Junction Assemblies – “Hyperneurons” . . . . . . . . . . . 215 6.3.6 The Next NCC Frontier – Neuronal Interiors and the Cytoskeleton . . . . . . . . . . . . . . . 216 6.4 The Neuronal Cytoskeleton . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 217 6.4.1 Microtubules and Networks inside Neurons . . . . . . . . . . . . 217 6.4.2 Microtubule Automata . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220 6.4.3 Protein Conformational Dynamics – Nature’s Bits and Qubits . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224 6.4.4 Anesthesia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225 6.5 Quantum Information Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226 6.5.1 Quantum Mechanics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226 6.5.2 Quantum Computation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228 6.5.3 Quantum Computing with Penrose OR . . . . . . . . . . . . . . . 229 6.6 The Quantum Unconscious . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230 6.7 Quantum Computation in Microtubules – The Orch OR Model . . 232 6.7.1 Specifics of Orch OR. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232 6.7.2 Decoherence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235 6.7.3 Testability and Falsifiability . . . . . . . . . . . . . . . . . . . . . . . . . 236 6.8 Applications of Orch OR to Consciousness and Cognition . . . . . . . 236 6.8.1 Visual Consciousness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236 6.8.2 Volition and Free-Will . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238 6.8.3 Quantum Associative Memory . . . . . . . . . . . . . . . . . . . . . . . 239 6.8.4 The Hard Problem of Conscious Experience . . . . . . . . . . . 239 6.8.5 What is Consciousness? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240 6.8.6 Consciousness and Evolution . . . . . . . . . . . . . . . . . . . . . . . . . 241 6.9 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242 Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244