Conscious events as orchestrated space-time selections

Stuart R Hameroff, Roger Penrose

Research output: Contribution to journalArticle

297 Citations (Scopus)

Abstract

What is consciousness? 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 comprised 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 space-time - as is described by Einstein's general theory of relativity - and its relation to the fundamental theory of matter - as described by quantum theory. This leads us to employ 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 (Penrose, 1994; 1996). 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. OR is taken as an instantaneous event - the climax of a self-organizing process in fundamental space-time - and a candidate for a conscious Whitehead-like '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 an OR process with the requisite characteristics to be occurring in cytoskeletal microtubules within the brain's neurons (Penrose and Hameroff, 1995; Hameroff and Penrose, 1995; 1996). In this model, quantum-superposed states develop in microtubule subunit proteins ('tubulins'), remain coherent, and recruit more superposed tubulins until a mass-time-energy threshold (related to quantum gravity) is reached. At that stage, self-collapse, or objective reduction (OR) abruptly occurs. We equate the pre-reduction, coherent superposition ('quantum computing') phase with pre-conscious processes, and each instantaneous (and non-computable) OR, or self-collapse, with a discrete conscious event. Sequences of OR events give rise to a 'stream' of consciousness. Microtubule-associated proteins can 'tune' the quantum oscillations of the coherent superposed states; the OR is thus self-organized, or 'orchestrated' ('Orch OR'). Each Orch OR event selects (non-computably) microtubule subunit states which regulate synaptic/neural functions using classical signalling. The quantum gravity threshold for self-collapse is relevant to consciousness, according to our arguments, because macroscopic superposed quantum states each have their own space-time geometries (Penrose, 1994; 1996). These geometries are also superposed, and in some way 'separated', but when sufficiently separated, the superposition of space-time geometries becomes signifcantly unstable, and reduce to a single universe state. Quantum gravity determines the scale of the instability; we contend that the actual choice of state made by Nature is non-computable. Thus each Orch OR event is a self-selection of space-time geometry, coupled to the brain through microtubules and other biomolecules. If conscious experience is intimately connected with the very physics underlying space-time structure, then Orch OR in microtubules indeed provides us with a completely new and uniquely promising perspective on the hard problem of consciousness.

Original languageEnglish (US)
Pages (from-to)36-53
Number of pages18
JournalJournal of Consciousness Studies
Volume3
Issue number1
StatePublished - 1996

Fingerprint

Consciousness
consciousness
Gravitation
event
Microtubules
Physics
mathematics
physics
brain
microtubules
gravity
Tubulin
Brain
Quantum Theory
Microtubule Proteins
experience
geometry
Microtubule-Associated Proteins
time
Conscious

ASJC Scopus subject areas

  • Philosophy
  • Psychology (miscellaneous)
  • Social Sciences(all)

Cite this

Conscious events as orchestrated space-time selections. / Hameroff, Stuart R; Penrose, Roger.

In: Journal of Consciousness Studies, Vol. 3, No. 1, 1996, p. 36-53.

Research output: Contribution to journalArticle

@article{3ab1e879e0d14573af7be20f25b0d39b,
title = "Conscious events as orchestrated space-time selections",
abstract = "What is consciousness? 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 comprised 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 space-time - as is described by Einstein's general theory of relativity - and its relation to the fundamental theory of matter - as described by quantum theory. This leads us to employ 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 (Penrose, 1994; 1996). 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. OR is taken as an instantaneous event - the climax of a self-organizing process in fundamental space-time - and a candidate for a conscious Whitehead-like '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 an OR process with the requisite characteristics to be occurring in cytoskeletal microtubules within the brain's neurons (Penrose and Hameroff, 1995; Hameroff and Penrose, 1995; 1996). In this model, quantum-superposed states develop in microtubule subunit proteins ('tubulins'), remain coherent, and recruit more superposed tubulins until a mass-time-energy threshold (related to quantum gravity) is reached. At that stage, self-collapse, or objective reduction (OR) abruptly occurs. We equate the pre-reduction, coherent superposition ('quantum computing') phase with pre-conscious processes, and each instantaneous (and non-computable) OR, or self-collapse, with a discrete conscious event. Sequences of OR events give rise to a 'stream' of consciousness. Microtubule-associated proteins can 'tune' the quantum oscillations of the coherent superposed states; the OR is thus self-organized, or 'orchestrated' ('Orch OR'). Each Orch OR event selects (non-computably) microtubule subunit states which regulate synaptic/neural functions using classical signalling. The quantum gravity threshold for self-collapse is relevant to consciousness, according to our arguments, because macroscopic superposed quantum states each have their own space-time geometries (Penrose, 1994; 1996). These geometries are also superposed, and in some way 'separated', but when sufficiently separated, the superposition of space-time geometries becomes signifcantly unstable, and reduce to a single universe state. Quantum gravity determines the scale of the instability; we contend that the actual choice of state made by Nature is non-computable. Thus each Orch OR event is a self-selection of space-time geometry, coupled to the brain through microtubules and other biomolecules. If conscious experience is intimately connected with the very physics underlying space-time structure, then Orch OR in microtubules indeed provides us with a completely new and uniquely promising perspective on the hard problem of consciousness.",
author = "Hameroff, {Stuart R} and Roger Penrose",
year = "1996",
language = "English (US)",
volume = "3",
pages = "36--53",
journal = "Journal of Consciousness Studies",
issn = "1355-8250",
publisher = "Imprint Academic",
number = "1",

}

TY - JOUR

T1 - Conscious events as orchestrated space-time selections

AU - Hameroff, Stuart R

AU - Penrose, Roger

PY - 1996

Y1 - 1996

N2 - What is consciousness? 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 comprised 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 space-time - as is described by Einstein's general theory of relativity - and its relation to the fundamental theory of matter - as described by quantum theory. This leads us to employ 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 (Penrose, 1994; 1996). 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. OR is taken as an instantaneous event - the climax of a self-organizing process in fundamental space-time - and a candidate for a conscious Whitehead-like '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 an OR process with the requisite characteristics to be occurring in cytoskeletal microtubules within the brain's neurons (Penrose and Hameroff, 1995; Hameroff and Penrose, 1995; 1996). In this model, quantum-superposed states develop in microtubule subunit proteins ('tubulins'), remain coherent, and recruit more superposed tubulins until a mass-time-energy threshold (related to quantum gravity) is reached. At that stage, self-collapse, or objective reduction (OR) abruptly occurs. We equate the pre-reduction, coherent superposition ('quantum computing') phase with pre-conscious processes, and each instantaneous (and non-computable) OR, or self-collapse, with a discrete conscious event. Sequences of OR events give rise to a 'stream' of consciousness. Microtubule-associated proteins can 'tune' the quantum oscillations of the coherent superposed states; the OR is thus self-organized, or 'orchestrated' ('Orch OR'). Each Orch OR event selects (non-computably) microtubule subunit states which regulate synaptic/neural functions using classical signalling. The quantum gravity threshold for self-collapse is relevant to consciousness, according to our arguments, because macroscopic superposed quantum states each have their own space-time geometries (Penrose, 1994; 1996). These geometries are also superposed, and in some way 'separated', but when sufficiently separated, the superposition of space-time geometries becomes signifcantly unstable, and reduce to a single universe state. Quantum gravity determines the scale of the instability; we contend that the actual choice of state made by Nature is non-computable. Thus each Orch OR event is a self-selection of space-time geometry, coupled to the brain through microtubules and other biomolecules. If conscious experience is intimately connected with the very physics underlying space-time structure, then Orch OR in microtubules indeed provides us with a completely new and uniquely promising perspective on the hard problem of consciousness.

AB - What is consciousness? 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 comprised 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 space-time - as is described by Einstein's general theory of relativity - and its relation to the fundamental theory of matter - as described by quantum theory. This leads us to employ 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 (Penrose, 1994; 1996). 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. OR is taken as an instantaneous event - the climax of a self-organizing process in fundamental space-time - and a candidate for a conscious Whitehead-like '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 an OR process with the requisite characteristics to be occurring in cytoskeletal microtubules within the brain's neurons (Penrose and Hameroff, 1995; Hameroff and Penrose, 1995; 1996). In this model, quantum-superposed states develop in microtubule subunit proteins ('tubulins'), remain coherent, and recruit more superposed tubulins until a mass-time-energy threshold (related to quantum gravity) is reached. At that stage, self-collapse, or objective reduction (OR) abruptly occurs. We equate the pre-reduction, coherent superposition ('quantum computing') phase with pre-conscious processes, and each instantaneous (and non-computable) OR, or self-collapse, with a discrete conscious event. Sequences of OR events give rise to a 'stream' of consciousness. Microtubule-associated proteins can 'tune' the quantum oscillations of the coherent superposed states; the OR is thus self-organized, or 'orchestrated' ('Orch OR'). Each Orch OR event selects (non-computably) microtubule subunit states which regulate synaptic/neural functions using classical signalling. The quantum gravity threshold for self-collapse is relevant to consciousness, according to our arguments, because macroscopic superposed quantum states each have their own space-time geometries (Penrose, 1994; 1996). These geometries are also superposed, and in some way 'separated', but when sufficiently separated, the superposition of space-time geometries becomes signifcantly unstable, and reduce to a single universe state. Quantum gravity determines the scale of the instability; we contend that the actual choice of state made by Nature is non-computable. Thus each Orch OR event is a self-selection of space-time geometry, coupled to the brain through microtubules and other biomolecules. If conscious experience is intimately connected with the very physics underlying space-time structure, then Orch OR in microtubules indeed provides us with a completely new and uniquely promising perspective on the hard problem of consciousness.

UR - http://www.scopus.com/inward/record.url?scp=0030306506&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0030306506&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0030306506

VL - 3

SP - 36

EP - 53

JO - Journal of Consciousness Studies

JF - Journal of Consciousness Studies

SN - 1355-8250

IS - 1

ER -