The nature of consciousness, its occurrence in the brain and its ultimate place in the universe are unknown. Probably the most interesting attempt to create a quantum theory of consciousness is that of Roger Penrose (recipient of the 2020 Nobel Prize for Physics) and an American anaesthesiologist Stuart Hameroff. They are both well known for their studies of consciousness and for the thesis that consciousness originates from quantum states in neural microtubules. The starting point for this article are the authors’ considerations contained in their joint work (Penrose & Hameroff, 2017). This paper also proposes an initial attempt to combine this theory with quantum logic.
The nature of consciousness, its occurrence in the brain and its ultimate place in the universe are unknown. Probably the most interesting attempt to create a quantum theory of consciousness is that of Roger Penrose (recipient of the 2020 Nobel Prize for Physics) and an American anaesthesiologist Stuart Hameroff. They are both well known for their studies of consciousness and for the thesis that consciousness originates from quantum states in neural microtubules. The starting point for this article are the authors’ considerations contained in their joint work (Penrose & Hameroff, 2017). This paper also proposes an initial attempt to combine this theory with quantum logic.
The nature of consciousness, its occurrence in the brain, and its ultimate place in the universe are unknown. We proposed in the mid 1990's that consciousness depends on biologically 'orchestrated' quantum computations in collections of microtubules within brain neurons, that these quantum computations correlate with and regulate neuronal activity, and that the continuous Schrodinger evolution of each quantum computation terminates in accordance with the specific Diosi‐Penrose (DP) scheme of 'objective reduction' of the quantum state (OR). This orchestrated OR activity (Orch OR) is taken to result in a moment of conscious awareness and/or choice. This particular (DP) form of OR is taken to be a quantum-gravity process related to the fundamentals of spacetime geometry, so Orch OR suggests a connection between brain biomolecular processes and fine-scale structure of the universe. Here we review and update Orch OR in light of criticisms and developments in quantum biology, neuroscience, physics and cosmology. We conclude that consciousness plays an intrinsic role in the universe.
Abstract In neuroscience, the flow of time is a conscious experience produced by the brain. But in physics, time is either a process, or a dimension in four-dimensional spacetime geometry. Could all three explanations be correct? The Penrose–Hameroff ‘Orch OR’ theory suggests consciousness is a sequence of discrete, irreversible quantum state reductions occurring at an objective threshold (‘objective reduction’, ‘OR’) a process in fundamental spacetime geometry. These ‘self-collapses’ of the quantum wavefunction are ‘orchestrated’ in microtubules inside brain neurons. Each Orch OR event selects microtubule states which purposefully regulate neuronal functions, and provide sequences of ‘NOW’ moments of conscious experience. Connected to fundamental spacetime geometry by Penrose ‘OR’, consciousness is quantum state reduction, a set of irreversible steps which ‘ratchet forward’ in the fine scale geometry of the universe, creating a flow of time.
As generally accepted, consciousness or mind and material brain are closely related to each other; but how? Quantum mechanics is a new pathway to understand the hard problem of consciousness and its relation to the brain. Consciousness has specific properties such as unity, irreducibility, non-locality, etc. The completely different features of classical physics (locality, reducibility, determinacy, etc.) hindered the success of scientists to study consciousness. But quantum mechanics with its features (non-locality, irreducibility, indeterminacy, etc.) gave scientists hope to study consciousness. Several quantum approaches to consciousness have been proposed in recent decades; the most important point about these approaches is that each one has used its own philosophy to determine its viewpoint about the mind’s nature and even its quantum approach. In general, all scientific theories are based on some metaphysical principles which come from the worldview of scientists. In this article four contemporary approaches are discussed: The Eccles-Beck, Stapp, Penrose-Hameroff, and Avicenna-Bohm theories; philosophical and scientific points are highlighted for each of them. Finally, the theory of Top-Down Causation is discussed because we think it can provide a fertile philosophical ground for theories of “mind-brain relation” and “quantum consciousness”.
This article explores the Orchestrated Objective Reduction hypothesis proposed by Roger Penrose and Stuart Hameroff, which posits that human consciousness arises from quantum-mechanical processes within the brain rather than classical algorithmic computation. The author details how tubulin proteins within neuronal microtubules are suggested to function as qubits that sustain quantum superposition and entanglement by isolating signals from environmental decoherence. Gravitational fluctuations are hypothesized to trigger the objective reduction of these quantum states, generating discrete moments of awareness that form a continuous stream of consciousness. Despite theoretical criticisms regarding the weakness of gravitational influences and the prevalence of thermal decoherence, the paper highlights recent experimental evidence in quantum biology, such as sustained photon luminescence in microtubules, that supports the feasibility of long-lasting quantum states in biological structures.
The study examines a problematic hypothesis of possible approaches to identifying the quantum physical foundations of the functioning of consciousness. The authors proceed from the fact that in modern conditions, not a single science, nor all sciences taken together, gives a final answer to the question of the “mechanism” of the origin of thought. However, this does not mean at all that research in this direction needs to be stopped. The authors express confidence that modern and subsequent research into the “quantum concept of consciousness” will lead to the identification of previously unknown patterns, opening the way to the formation of new principles and approaches. As an example, the corresponding Penrose - Hameroff concept is considered. Quantum mechanics complements the tools of neurobiology and other branches of neuroscience, which together form an interdisciplinary field of knowledge that is dynamically growing and developing. The authors are not apologists for the omnipotence of quantum physics. Quantum correlates of consciousness actually mean that it is not today’s quantum mechanics itself that explains the emergence of mental states, but the fact that in the birth of these states it is essential that in the very process of the formation of neurodynamic impulses in the neurons of the cerebral cortex that generate mental states, there are processes of quantum nature. It should also be recognized that the quantum-molecular level (nanolevel) of processes in the neurons of the brain really exists and it is this that is the source of proto-consciousness. Science strives to move forward, new research programs are emerging within the framework of quantum biology, quantum psychology, quantum information science, which in turn can shed light on the hypothesis of the “quantum concept of consciousness.”
The scientific approach to understand the nature of consciousness revolves around the study of the human brain. Neurobiological studies that compare the nervous system of different species have accorded the highest place to humans on account of various factors that include a highly developed cortical area comprising of approximately 100 billion neurons, that are intrinsically connected to form a highly complex network. Quantum theories of consciousness are based on mathematical abstraction and the Penrose–Hameroff Orch-OR theory is one of the most promising ones. Inspired by the Penrose–Hameroff Orch-OR theory, Behrman et al. have simulated a quantum Hopfield neural network with the structure of a microtubule. They have used an extremely simplified model of the tubulin dimers with each dimer represented simply as a qubit, a single quantum two-state system. The extension of this model to n-dimensional quantum states or n-qudits presented in this work holds considerable promise for even higher mathematical abstraction in modelling consciousness systems.