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microtubules
Also known as: Microtubuli
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Quantum Models of Consciousness from a Quantum Information ... arxiv.org Dec 20, 2024 17 facts
referenceT. J. A. Craddock, D. Friesen, J. Mane, S. Hameroff, and J. A. Tuszynski analyzed the feasibility of coherent energy transfer in microtubules in a 2014 article published in the Journal of the Royal Society Interface.
claimThe Orch OR theory posits that information processing in the brain occurs at the level of microtubules, which shape neurons and provide their unique architecture, though this theory conflicts with established principles of neuroscience.
procedureIn the theoretical model for exciton transport within microtubules, the biorthogonal eigenspectrum was calculated by diagonalizing the non-Hermitian Hamiltonian for a system of up to 100 spirals of 13 microtubule protofilaments, with each spiral containing 104 tryptophan (Trp) dipoles.
claimThe authors of the paper 'Quantum Models of Consciousness from a Quantum Information Perspective' explored several quantum brain theories, including consciousness occurring within microtubules, consciousness within the electromagnetic field, and cognition via the Posner cluster model.
referenceA theoretical model for exciton transport within microtubules treats aromatic tryptophan amino acids (Trp) as photoactive molecular sites through which a single exciton delocalizes, utilizing the non-Hermitian Hamiltonian approach.
referenceStuart Hameroff, A. Nip, M. Porter, and J. Tuszynski investigated conduction pathways in microtubules, biological quantum computation, and consciousness in a 2002 study published in Biosystems.
claimThe quantum information science framework can be used to extend the non-Hermitian Hamiltonian approach to a quantum master equation approach, allowing for the modeling of complete photoexcitation dynamics in microtubules, including the influence of the surrounding environment.
claimStuart Hameroff integrated the concept of orchestrated objective reduction with biological systems by proposing that microtubules, which are large polymers essential to cellular structure and function, could provide a framework for quantum processes within neurons.
referenceG. Celardo, M. Angeli, T. Craddock, and P. Kurian investigated the existence of superradiant excitonic states in microtubules in a 2019 article published in the New Journal of Physics.
claimPhotoexcitation in microtubules spreads ballistically along the longitudinal axis, and superradiance demonstrates robustness to disorder even when excitation energy is uniformly distributed across tryptophan (Trp) dipole sites.
claimThe density matrix formalism provides a framework for quantifying exciton delocalization in microtubules using measures of quantum coherence, a methodology that parallels the approach used to quantify proton delocalization in water ice systems.
claimIn the theoretical model for exciton transport within microtubules, the imaginary part of the complex eigenvalues represents the decay width, which determines the coupling of the extended excitonic state with the electromagnetic field.
claimSuperradiance in microtubules corresponds to the lowest excitonic state for systems containing more than 12 spirals, and this superradiance is destroyed by either full or partial randomization of tryptophan (Trp) dipole orientations.
claimStuart Hameroff proposed that quantum coherence in microtubules serves as a neural basis for emergent consciousness in a 1994 article published in the Journal of Consciousness Studies.
claimMicrotubules are hollow tubes composed of tubulin dimers that contain electrons capable of delocalizing within the aromatic rings of tubulin molecules.
claimProbability-based approaches to witnessing exciton delocalization in microtubules can be misleading, particularly when the microtubule is an open system, because the simultaneous presence of an exciton at two different tryptophan (Trp) sites with nonzero probabilities does not necessarily imply delocalization if the off-diagonal term of the density matrix coupling those sites is zero.
referenceT. J. Craddock and J. A. Tuszynski examined the role of microtubules in cognitive brain functions in a 2007 article published in NeuroQuantology.
Quantum Approaches to Consciousness plato.stanford.edu Nov 30, 2004 8 facts
claimThe results from Bandyopadhyay’s lab regarding microtubules initiated significant attention and commentary, as noted by Hameroff and Penrose in 2014.
claimSahu et al. (2013) provided evidence for vibrational resonances and conductivity features in microtubules, supporting the proposal that microtubules act as quantum computing devices.
referenceMatti Pitkänen published the article "New results about microtubuli as quantum systems" in the Journal of Nonlocality in 2014.
imageThe figure illustrates microtubuli and neurofilaments with a width of approximately 700nm, and tubulin dimers composed of α- and β-monomers that constitute a microtubule.
claimStuart Hameroff, an anaesthesiologist, collaborated with Roger Penrose to suggest that microtubules are the location where quantum state reductions can effectively occur.
claimThe cytoskeleton of a single neuron consists of protein networks made of neurofilaments and microtubuli, which are essential for transport processes within the cell.
claimRoger Penrose and Stuart Hameroff developed a scenario claiming that quantum theory is effective for consciousness, specifically arguing that elementary acts of consciousness are non-algorithmic and neurophysiologically realized as gravitation-induced reductions of coherent superposition states in microtubuli.
claimRoger Penrose and Stuart Hameroff have argued that microtubuli are the potential location for quantum state reductions in the brain.
Quantum Approaches to Consciousness plato.stanford.edu Nov 30, 2004 7 facts
claimMax Tegmark concludes that the lifetime of tubulin superpositions is too short to be significant for neurophysiological processes in microtubules because typical microtubule processes occur on the order of milliseconds.
claimStuart Hameroff's proposal uses tubulins in microtubuli as the substrate to embed Roger Penrose's theoretical framework neurophysiologically.
claimRoger Penrose and Stuart Hameroff have argued that microtubuli are the biological structures where gravitation-induced quantum state reductions related to consciousness might occur.
measurementMicrotubuli are long polymers usually constructed of 13 longitudinal alpha and beta-tubulin dimers arranged in a tubular array with an outside diameter of about 25 nm.
claimStuart Hameroff suggested that microtubules are locations where reductions of quantum states can effectively occur.
claimRoger Penrose and Stuart Hameroff argue that elementary acts of consciousness are non-algorithmic (non-computable) and are neurophysiologically realized as gravitation-induced reductions of coherent superposition states in microtubuli.
claimThe focus on microtubules in the Penrose-Hameroff hypothesis is motivated by the need for protected locations where quantum states can persist long enough to undergo gravitational reduction before interacting with the warm, wet environment of the brain.
Quantum Approaches to Consciousness plato.stanford.edu Nov 30, 2004 5 facts
referenceEmpirical research regarding potential quantum interactions of anesthetics in microtubuli has been conducted by Li et al. (2018), Burdick et al. (2019), and Zadeh-Haghighi and Simon (2022).
claimRoger Penrose and Stuart Hameroff proposed that microtubules function as quantum computing devices within the brain.
claimThe quantum consciousness proposal by Roger Penrose and Stuart Hameroff extends beyond present-day quantum theory and has initiated empirical research into the function of anesthetics and the operation of microtubules.
claimAfter more than three decades, the Penrose-Hameroff approach has inspired research into quantum effects on consciousness across various theoretical and empirical groups, covering areas from microtubuli to synaptic processes and large-scale brain regions.
referenceBandyopadhyay’s laboratory in Japan provided evidence for vibrational resonances and conductivity features in microtubules, which are characteristics expected if microtubules function as macroscopic quantum systems, as reported by Sahu et al. in 2013.
Quantum Mechanics And Consciousness: The Physics Of Mind quantumzeitgeist.com Apr 17, 2025 4 facts
claimThe Orchestrated Objective Reduction (Orch-OR) theory, proposed by Roger Penrose and Stuart Hameroff, suggests that consciousness arises from quantum computations occurring in microtubules within neurons.
claimRoger Penrose and Stuart Hameroff proposed the Orchestrated Objective Reduction (Orch OR) hypothesis, which posits that microtubules in brain neurons maintain quantum states that affect consciousness.
claimThe hypothesis that tubulin proteins within microtubules act as qubits is largely theoretical and lacks concrete experimental evidence or empirical backing.
claimMicrotubules are integral components of the cell's cytoskeleton, primarily involved in structural support and intracellular transport.
Consciousness (Stanford Encyclopedia of Philosophy/Fall 2025 ... plato.stanford.edu Jun 18, 2004 2 facts
claimPhysicist Roger Penrose (1989, 1994) and anesthesiologist Stuart Hameroff (1998) proposed a model of consciousness where consciousness arises through quantum effects occurring within microtubules, which are subcellular structures internal to neurons.
claimIn the Penrose-Hameroff model, the environment inside microtubules is suitable for objective collapses, and the resulting self-collapses produce a coherent flow that regulates neuronal activity and enables non-algorithmic mental processes.
Moving Forward on the Problem of Consciousness - David Chalmers consc.net 2 facts
perspectiveDavid Chalmers critiques the Hameroff-Penrose theory for focusing primarily on the physics of reduction in microtubules while leaving the explanation of experience largely unaddressed.
claimDavid Chalmers notes that Stuart Hameroff and Roger Penrose's work clarifies that they view consciousness as fundamental, rather than explaining it wholly in terms of quantum action in microtubules.
Critique of Panpsychism: Philosophical Coherence and Scientific ... thequran.love May 7, 2025 1 fact
claimSome theorists have speculated that if consciousness is fundamental, it could play a role in quantum processes, such as the 'orchestrated collapse' in microtubules.
Quantum mechanics and the puzzle of human consciousness alleninstitute.org May 30, 2024 1 fact
claimRoger Penrose and anesthesiologist Stuart Hameroff hypothesize that microtubules, which are small structures found in neurons and other cells, weave moments of 'proto-consciousness' together to form full consciousness.
Six Theories of Consciousness - Mind Matters mindmatters.ai Mar 2, 2026 1 fact
claimRoger Penrose and Stuart Hameroff proposed that tiny structures in brain cells called microtubules could support quantum effects that contribute to human awareness.
Medicinal plants and human health: a comprehensive review of ... link.springer.com Nov 5, 2025 1 fact
claimTerpenoids, including paclitaxel and docetaxel, arrest the cell cycle at the G2/M phase by stabilizing microtubules.
Consciousness-Induced Quantum State Reduction - Nova Spivack novaspivack.com Jun 2, 2025 1 fact
claimPenrose (1989) and Hameroff & Penrose (2014) proposed biophysical models linking consciousness to objective collapse mechanisms involving microtubules, though Tegmark (2000) challenged these models regarding biological feasibility and experimental verification.
AI Sessions #9: The Case Against AI Consciousness (with Anil Seth) conspicuouscognition.com Feb 17, 2026 1 fact
perspectiveAnil Seth argues that simulating biological details, such as mitochondria or microtubules, in a digital computer does not make the simulation conscious unless consciousness is constitutively computational.
Bridging the Gap Between LLMs and Evolving Medical Knowledge arxiv.org Jun 29, 2025 1 fact
measurementThe hyperstabilization of microtubules is related to the cross-linking of DNA, and LLM-based analysis of this relationship received a 9.0/10 relevance rating, with the model showing a 20% increase in accuracy for scenarios involving cellular structure interactions.
Quantum Theory of Consciousness - Scirp.org. scirp.org 1 fact
claimThe authors of 'Quantum Theory of Consciousness' argue that neural systems, membranes, microtubules, DNA, and living structures have greater similarity to crystals, semiconductor materials, superconductors, lasers, and superfluids than to classical mechanical systems, necessitating the use of quantum physics to study them.