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Orchestrated objective reduction (Orch-OR) is a hypothesis that consciousness in the brain originates from processes ''inside'' neurons, rather than from connections ''between'' neurons as in the conventional view. The mechanism is held to be a quantum physics process called ''objective reduction'' which is ''orchestrated'' by molecular structures called microtubules. The hypothesis, which was put forward in the early 1990s by theoretical physicist Roger Penrose and anaesthesiologist and psychologist Stuart Hameroff, has so far been rejected by the majority of cognitive scientists. ==Overview== Orchestrated objective reduction claims that consciousness derives from deeper level, finer scale quantum activities inside the cells, most prevalent in the brain's neurons. It combines approaches from the radically different angles of molecular biology, neuroscience, quantum physics, pharmacology, philosophy, quantum information theory, and aspects of quantum gravity. While mainstream theories assume that consciousness emerges as the complexity of the computations performed by cerebral neurons increases, Orch-OR posits that consciousness is based on non-computable quantum processing performed by qubits formed collectively on the microtubules of the cells, a process significantly amplified in the neurons. The qubits are based on oscillating dipoles forming superposed resonance rings in helical pathways throughout microtubule lattices. The oscillations are either electric, due to charge separation from London forces, or (most favorably) magnetic, due to electron spin — and possibly also due to nuclear spins (which can remain isolated for longer periods of time), and which occur in gigahertz, megahertz and kilohertz frequency ranges.〔 The ''orchestration'' refers to the hypothetical process by which connective proteins, such as microtubule-associated proteins (MAPs), influence or orchestrate the state reduction of the qubits by modifying the spacetime-separation of their superimposed states. The latter is based on Penrose's objective collapse theory for interpreting quantum mechanics, which postulates the existence of an objective threshold governing the collapse of quantum-states, related to the difference of the space-time curvature of these states in the fine scale structure of the universe. The basis of Orch-OR has been harshly criticized from its inception by mathematicians,〔LaForte, Geoffrey, Patrick J. Hayes, and Kenneth M. Ford 1998.''(Why Gödel's Theorem Cannot Refute Computationalism )''. Artificial Intelligence, 104:265–286.〕〔Krajewski, Stanislaw 2007. ''On Gödel's Theorem and Mechanism: Inconsistency or Unsoundness is Unavoidable in any Attempt to 'Out-Gödel' the Mechanist.'' Fundamenta Informaticae 81, 173–181. Reprinted in (in Logic, Philosophy and Foundations of Mathematics and Computer Science:In Recognition of Professor Andrzej Grzegorczyk (2008), p. 173 )〕 philosophers,〔Boolos, George, et al. 1990. ''An Open Peer Commentary on The Emperor's New Mind.'' Behavioral and Brain Sciences 13 (4) 655.〕〔Davis, Martin 1993. ''How subtle is Gödel's theorem? More on Roger Penrose.'' Behavioral and Brain Sciences, 16, 611–612. Online version at Davis' faculty page at http://cs.nyu.edu/cs/faculty/davism/〕〔Lewis, David K. 1969.''(Lucas against mechanism )''. Philosophy 44 231–233.〕〔Putnam, Hilary 1995. ''Review of Shadows of the Mind.'' In Bulletin of the American Mathematical Society 32, 370–373 (also see Putnam's less technical criticisms in his (New York Times review ))〕 and scientists, prompting the authors to revise and elaborate many of the peripheral assumptions of the theory, but the core ideas have remained the same. The criticism so far has been concentrated on three issues: Penrose's interpretation of Gödel's theorem which postulates that consciousness is non-computable; Penrose's abductive reasoning linking non-computability to quantum processes; unsuitability of the brain to host the seemingly delicate quantum phenomena required by the theory, since it is considered too ''"warm, wet and noisy"'' to avoid decoherence. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Orchestrated objective reduction」の詳細全文を読む スポンサード リンク
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