Stuart Hameroff

Last updated
Stuart Hameroff
Stuart Hameroff TASC2008.JPG
Hameroff in 2008
Born (1947-07-16) 16 July 1947 (age 76)
Buffalo, New York, United States
Nationality American
CitizenshipUnited States
Alma mater University of Pittsburgh (B.S.)
Hahnemann University Hospital (M.D.)
Known for Consciousness studies
Toward a Science of Consciousness
Scientific career
Fields Anesthesiologist
Institutions University of Arizona

Stuart Hameroff (born July 16, 1947) is an American anesthesiologist and professor at the University of Arizona known for his studies of consciousness and his controversial contention that consciousness originates from quantum states in neural microtubules. He is the lead organizer of the Science of Consciousness conference.

Contents

Career

Hameroff received his BS degree from the University of Pittsburgh and his MD degree from Hahnemann University Hospital, where he studied before it became part of the Drexel University College of Medicine. He took an internship at the Tucson Medical Center in 1973. From 1975 onwards, he has spent the whole of his career at the University of Arizona, becoming professor in the Department of Anesthesiology and Psychology and director for the Center for Consciousness Studies, both in 1999, and finally Emeritus professor for Anesthesiology and Psychology in 2003.

Theory

At the very beginning of Hameroff's career, while he was at Hahnemann, cancer-related research work piqued his interest in the part played by microtubules in cell division, and led him to speculate that they were controlled by some form of computing. It also suggested to him that part of the solution of the problem of consciousness might lie in understanding the operations of microtubules in brain cells, operations at the molecular and supramolecular level. [1]

Hameroff's first book Ultimate Computing (1987) argues that microtubes allow for computation sufficient to explain consciousness. [2] The main substance of this book dealt with the scope for information processing in biological tissue and especially in microtubules and other parts of the cytoskeleton. Hameroff argued that these subneuronal cytoskeleton components could be the basic units of processing rather than the neurons themselves. The book was primarily concerned with information processing, with consciousness a secondary consideration.

Separately from Hameroff, the English mathematical physicist Roger Penrose had published his first book on consciousness, The Emperor's New Mind , in 1989. [3] On the basis of Gödel's incompleteness theorems, he argued that the brain could perform functions that no computer or system of algorithms could. From this it could follow that consciousness itself might be fundamentally non-algorithmic and therefore impossible to model as a classical Turing machine type of computer. This conflicts with the idea that consciousness is explainable mechanistically, the prevailing view among neuroscientists and artificial intelligence researchers.

Penrose saw the principles of quantum theory as providing an alternative process through which consciousness could arise. He further argued that this non-algorithmic process required a new form of the quantum wave reduction, later given the name objective reduction (OR), which could link the brain to the fundamental spacetime geometry.

Hameroff was inspired by Penrose's book to contact Penrose regarding his own theories about the mechanism of anesthesia, and how it specifically targets consciousness via action on neural microtubules. The two met in 1992, and Hameroff suggested that the microtubules were a good candidate site for a quantum mechanism in the brain. Penrose was interested in the mathematical features of the microtubule lattice, and over the next two years the two collaborated in formulating the orchestrated objective reduction (Orch-OR) model of consciousness. Following this collaboration, Penrose published his second consciousness book, Shadows of the Mind (1994). [4]

Over the years since 1994, Hameroff has been active in promoting the Orch-OR model of consciousness through his web site and lectures. [5]

Criticism

Hameroff and Penrose's model has been met with skepticism from many disciplines. [6] [7] Rick Grush and Patricia Churchland, argued that "physiological evidence indicates that consciousness does not directly depend on microtubule properties in any case". [8]

In 2000, physicist Max Tegmark calculated that quantum states in microtubules would survive for only 10−13 seconds, too brief to be of any significance for neural processes. [9] [10] Hameroff and the physicists Scott Hagan and Jack Tuszynski replied to Tegmark arguing that microtubules could be shielded against the environment of the brain and that Tegmark had used his own criteria for the reduction of the wavefunction, and did not use Penrose's OR, which is the basic assumption behind the whole theory. [11] Christof Koch and Klaus Hepp also agreed that quantum coherence does not play, or does not need to play any major role in neurophysiology. [12] [13] Koch and Hepp concluded that "[t]he empirical demonstration of slowly decoherent and controllable quantum bits in neurons connected by electrical or chemical synapses, or the discovery of an efficient quantum algorithm for computations performed by the brain, would do much to bring these speculations from the 'far-out' to the mere 'very unlikely'." [12] In 2022, a group of Italian physicists conducted several experiments that failed to provide evidence in support of a gravity-related quantum collapse model of consciousness, weakening the possibility of a quantum explanation for consciousness. [14] [15]

Toward a science of consciousness

Hameroff was the lead organizer of the first Tucson Toward a Science of Consciousness meeting in 1994 that brought together approximately 300 people interested in consciousness studies (e.g., David Chalmers, Christof Koch, Bernard Baars, Roger Penrose, Benjamin Libet). Hameroff remains co-organizer of this influential annual conference (now simply Science of Consciousness). The first conference is widely regarded as a landmark event within the field of consciousness studies, and by bringing researchers from various disciplines together led to various useful synergies, resulting indirectly, for instance, in the formation of the Association for the Scientific Study of Consciousness, and more directly in the creation of the Center for Consciousness Studies at the University of Arizona, of which Hameroff is now the director. The Center for Consciousness Studies hosts meetings on the study of consciousness every two years, as well as sponsoring seminars on consciousness theory. The conference was described by the Chronicle of Higher Education as "the Stuart Show", and that its "anything goes" atmosphere is damaging the credibility of the field. [7]

In 2006, Hameroff participated in the first Beyond Belief conference, where his theories were criticized by Lawrence Krauss, among others. [6]

Film

Hameroff appeared as himself in the documentary film What tнe ♯$*! Do ωΣ (k)πow!? (2004). He serves as producer, writer and scientific advisor to an independent feature film called Mindville. Mindville is a feature-length motion picture that combines live action with animation and effects to present a journey into the mysteries of human consciousness.

Hameroff has been interviewed in season 2, episode 1 of Through the Wormhole .

Related Research Articles

<span class="mw-page-title-main">Consciousness</span> Awareness of internal and external existence

Consciousness, at its simplest, is awareness of internal and external existence. However, its nature has led to millennia of analyses, explanations and debate by philosophers, theologians, and all of science. Opinions differ about what exactly needs to be studied or even considered consciousness. In some explanations, it is synonymous with the mind, and at other times, an aspect of mind. In the past, it was one's "inner life", the world of introspection, of private thought, imagination and volition. Today, it often includes any kind of cognition, experience, feeling or perception. It may be awareness, awareness of awareness, or self-awareness either continuously changing or not. The disparate range of research, notions and speculations raises a curiosity about whether the right questions are being asked.

<span class="mw-page-title-main">Roger Penrose</span> English mathematical physicist (born 1931)

Sir Roger Penrose is an English mathematician, mathematical physicist, philosopher of science and Nobel Laureate in Physics. He is Emeritus Rouse Ball Professor of Mathematics in the University of Oxford, an emeritus fellow of Wadham College, Oxford, and an honorary fellow of St John's College, Cambridge, and University College London.

<i>The Emperors New Mind</i> Book by Sir Roger Penrose

The Emperor's New Mind: Concerning Computers, Minds and The Laws of Physics is a 1989 book by the mathematical physicist Roger Penrose.

<span class="mw-page-title-main">Panpsychism</span> View that mind is a fundamental feature of reality

In the philosophy of mind, panpsychism is the view that the mind or a mindlike aspect is a fundamental and ubiquitous feature of reality. It is also described as a theory that "the mind is a fundamental feature of the world which exists throughout the universe". It is one of the oldest philosophical theories, and has been ascribed to philosophers including Thales, Plato, Spinoza, Leibniz, William James, Alfred North Whitehead, Bertrand Russell, and Galen Strawson. In the 19th century, panpsychism was the default philosophy of mind in Western thought, but it saw a decline in the mid-20th century with the rise of logical positivism. Recent interest in the hard problem of consciousness and developments in the fields of neuroscience, psychology, and quantum physics have revived interest in panpsychism in the 21st century.

<span class="mw-page-title-main">Orchestrated objective reduction</span> Theory of a quantum origin of consciousness

Orchestrated objective reduction is a theory which postulates that consciousness originates at the quantum level inside neurons, rather than the conventional view that it is a product of connections between neurons. The mechanism is held to be a quantum process called objective reduction that is orchestrated by cellular structures called microtubules. It is proposed that the theory may answer the hard problem of consciousness and provide a mechanism for free will. The hypothesis was first put forward in the early 1990s by Nobel laureate for physics, Roger Penrose, and anaesthesiologist Stuart Hameroff. The hypothesis combines approaches from molecular biology, neuroscience, pharmacology, philosophy, quantum information theory, and quantum gravity.

Electromagnetic theories of consciousness propose that consciousness can be understood as an electromagnetic phenomenon.

<span class="mw-page-title-main">Christof Koch</span> American neurophysiologist

Christof Koch is a German-American neurophysiologist and computational neuroscientist best known for his work on the neural basis of consciousness. He is the president and chief scientist of the Allen Institute for Brain Science in Seattle. From 1986 until 2013, he was a professor at the California Institute of Technology.

Henry Pierce Stapp is an American mathematical physicist, known for his work in quantum mechanics, particularly the development of axiomatic S-matrix theory, the proofs of strong nonlocality properties, and the place of free will in the "orthodox" quantum mechanics of John von Neumann.

The Penrose interpretation is a speculation by Roger Penrose about the relationship between quantum mechanics and general relativity. Penrose proposes that a quantum state remains in superposition until the difference of space-time curvature attains a significant level.

<span class="mw-page-title-main">Quantum mysticism</span> Pseudo-science purporting to build on the principles of quantum mechanics

Quantum mysticism, sometimes referred pejoratively to as quantum quackery or quantum woo, is a set of metaphysical beliefs and associated practices that seek to relate consciousness, intelligence, spirituality, or mystical worldviews to the ideas of quantum mechanics and its interpretations. Quantum mysticism is considered pseudoscience and quackery by quantum mechanics experts.

<i>Shadows of the Mind</i> Book by Roger Penrose

Shadows of the Mind: A Search for the Missing Science of Consciousness is a 1994 book by mathematical physicist Roger Penrose that serves as a followup to his 1989 book The Emperor's New Mind: Concerning Computers, Minds and The Laws of Physics.

The quantum mind or quantum consciousness is a group of hypotheses proposing that local physical laws and interactions from classical mechanics or connections between neurons alone cannot explain consciousness, positing instead that quantum-mechanical phenomena, such as entanglement and superposition that cause nonlocalized quantum effects, interacting in smaller features of the brain than cells, may play an important part in the brain's function and could explain critical aspects of consciousness. These scientific hypotheses are as yet unvalidated, and they can overlap with quantum mysticism.

<span class="mw-page-title-main">Integrated information theory</span> Theory within consciousness research (proposed 2004)

Integrated information theory (IIT) proposes a mathematical model for the consciousness of a system. It comprises a framework ultimately intended to explain why some physical systems are conscious, and to be capable of providing a concrete inference about whether any physical system is conscious, to what degree, and what particular experience it is having; why they feel the particular way they do in particular states, and what it would take for other physical systems to be conscious.

<span class="mw-page-title-main">Klaus Hepp</span> Swiss theoretical physicist

Klaus Hepp is a German-born Swiss theoretical physicist working mainly in quantum field theory. Hepp studied mathematics and physics at Westfälischen Wilhelms-Universität in Münster and at the Eidgenössischen Technischen Hochschule (ETH) in Zurich, where, in 1962, with Res Jost as thesis first advisor and Markus Fierz as thesis second advisor, he received a doctorate for the thesis and at ETH in 1963 attained the rank of Privatdozent. From 1966 until his retirement in 2002 he was professor of theoretical physics there. From 1964 to 1966 he was at the Institute for Advanced Study in Princeton. Hepp was also Loeb Lecturer at Harvard and was at the IHÉS near Paris.

Jack Tuszyński is a Polish professor of oncology and physicist.

The Penrose–Lucas argument is a logical argument partially based on a theory developed by mathematician and logician Kurt Gödel. In 1931, he proved that every effectively generated theory capable of proving basic arithmetic either fails to be consistent or fails to be complete. Due to human ability to see the truth of formal system's Gödel sentences, it is argued that the human mind cannot be computed on a Turing machine that works on Peano arithmetic because the latter cannot see the truth value of its Gödel sentence, while human minds can. Mathematician Roger Penrose modified the argument in his first book on consciousness, The Emperor's New Mind (1989), where he used it to provide the basis of his theory of consciousness: orchestrated objective reduction.

<i>Quantum Night</i> 2016 Robert J. Sawyer novel

Quantum Night is a 2016 science-fiction thriller novel written by Canadian novelist Robert J. Sawyer. Set in 2020, the book touches on themes of quantum physics, psychology, current politics and ethics.

Models of consciousness are used to illustrate and aid in understanding and explaining distinctive aspects of consciousness. Sometimes the models are labeled theories of consciousness. Anil Seth defines such models as those that relate brain phenomena such as fast irregular electrical activity and widespread brain activation to properties of consciousness such as qualia. Seth allows for different types of models including mathematical, logical, verbal and conceptual models.

Quantum social science is an emerging field of interdisciplinary research which draws parallels between quantum physics and the social sciences. Although there is no settled consensus on a single approach, a unifying theme is that, while the social sciences have long modelled themselves on mechanistic science, they can learn much from quantum ideas such as complementarity and entanglement. Some authors are motivated by quantum mind theories that the brain, and therefore human interactions, are literally based on quantum processes, while others are more interested in taking advantage of the quantum toolkit to simulate social behaviours which elude classical treatment. Quantum ideas have been particularly influential in psychology but are starting to affect other areas such as international relations and diplomacy in what one 2018 paper called a "quantum turn in the social sciences".

Theories of holographic consciousness postulate that consciousness has structural and functional similarities to a hologram, in that the information needed to model the whole is contained within each constituent component.

References

  1. Danaylov, Nikola, ed. (12 Sep 2013). Stuart Hameroff on Singularity 1 on 1: Consciousness is More than Computation!. Singularity Weblog. Archived from the original on 2021-12-12. Retrieved 24 March 2014. Consciousness is the most important thing there is!
  2. Hameroff, Stuart (1987), Ultimate Computing, Elsevier ISBN   978-0444702838
  3. Penrose, Roger (1989) The Emperor's New Mind Oxford University Press
  4. Penrose, Roger (1994) Shadows of the Mind Oxford University Press
  5. "Quantum Consciousness - Quantum Consciousness".
  6. 1 2 Hameroff, Stuart; Ramachandran, V.S. (November 5, 2006). "Beyond Belief: Science, Reason, Religion & Survival: Session 4". The Science Network . Retrieved 2012-08-13.
  7. 1 2 Bartlett, Tom (6 June 2018). "Has Consciousness Lost Its Mind?". The Chronicle of Higher Education. Archived from the original on 17 June 2018. Retrieved 19 June 2018.
  8. Grush Rick, Churchland Patricia (1995). "Gap's in Penrose's Toilings". Journal of Consciousness Studies . 2 (1): 10–29. CiteSeerX   10.1.1.118.4783 . (also see article at IngentaConnect)
  9. Tegmark Max (2000). "Importance of quantum coherence in brain processes". Physical Review E. 61 (4): 4194–4206. arXiv: quant-ph/9907009 . Bibcode:2000PhRvE..61.4194T. doi:10.1103/physreve.61.4194. PMID   11088215. S2CID   17140058.
  10. Tegmark, Max (October 2000). "Why the brain is probably not a quantum computer" (PDF). Information Sciences. 128 (3–4): 155–179. doi:10.1016/S0020-0255(00)00051-7.
  11. Hagan Scott, Hameroff Stuart R, Tuszyński Jack A (2002). "Quantum computation in brain microtubules: Decoherence and biological feasibility". Physical Review E. 65 (6): 061901. arXiv: quant-ph/0005025 . Bibcode:2002PhRvE..65f1901H. doi:10.1103/physreve.65.061901. PMID   12188753. S2CID   11707566.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  12. 1 2 Koch, Christof; Hepp, Klaus (2006). "Quantum mechanics in the brain". Nature. 440 (7084): 611. Bibcode:2006Natur.440..611K. doi: 10.1038/440611a . PMID   16572152. S2CID   5085015.
  13. Hepp, K. (27 September 2012). "Coherence and decoherence in the brain". J. Math. Phys. 53 (9): 095222. Bibcode:2012JMP....53i5222H. doi:10.1063/1.4752474 . Retrieved 8 August 2013.
  14. "Collapsing a leading theory for the quantum origin of consciousness".
  15. Derakhshani, Maaneli; Diósi, Lajos; Laubenstein, Matthias; Piscicchia, Kristian; Curceanu, Catalina (2022). "At the crossroad of the search for spontaneous radiation and the Orch OR consciousness theory". Physics of Life Reviews. 42: 8–14. Bibcode:2022PhLRv..42....8D. doi:10.1016/j.plrev.2022.05.004. PMID   35617922. S2CID   248868080.

Further reading