Orch-OR: Orchestrated objective reduction – The quantum brain hypothesis à la Penrose & Hameroff | ॐ Homepage of Dr. Christopher B. Germann (Ph.D., M.Sc., B.Sc. / Marie Curie Alumnus)

Orch-OR

Orchestrated objective reduction

The quantum brain hypothesis à la Penrose & Hameroff

Christopher B. Germann (Marie Curie Alumnus / Ph.D., M.Sc., B.Sc.)

2019

The eminent Oxford professor Sir Roger Penrose and anaesthesiologist Stuart Hameroff for-

mulated a neurophysiological model which postulates quantum processes within the neu-

ronal architecture of the brain. The hypothesis is based on the premise that the neuronal

cytoskeleton isolates microtubule (Conde & Cáceres, 2009) from the environment and that

it forms a protective shield which prevents decoherence from interfering with the extremely

fragile quantum processes (viz., through the process of “Einselection”

(Zurek, 2003)). Ac-

cording to the Orch-OR hypothesis, action potentials are generated when superpositional

quantum states at the microtubular level collapse. Each cortical dendrite contains micro-

tubule (located at the gap junction; see Figure 1) and this creates a network structure of

microtubule which can generate a coherent quantum state. The frequency of the micro-

tubular wave function collapse is hypothesised to lie within the EEG spectrum of approxi-

mately 40Hz, i.e., within the gamma range (Fitzgibbon, Pope, MacKenzie, Clark, &

Willoughby, 2004). The collapse of Ψ within neuronal dendritic-somatic microtubules is

thought to be the fundamental basis of consciousness. The frequency of collapse is esti-

mated to occur once every 25ms. Furthermore, the truly interdisciplinary Orch-OR theory

“suggests a connection between brain biomolecular processes and fine-scale structure of the

universe” (Penrose & Hameroff, 2011, p. 1), i.e., it postulates an intimate relation between

neuronal processes and space-time geometry. The theory explicitly raises the question if

“the conscious mind [is] subtly linked to a basic level of the universe” (Hameroff, 1998)? A

panpsychist perspective (Chalmers, 2015, 2016)

which is compatible with the Fechnerian

psychophysics point of view (as it links the psychological with the physical) and also with

the Vedāntic perspective on consciousness (Vaidya & Bilimoria, 2015). However, the theory

has been severely criticized (e.g., the decoherence problem) and is currently a hotly de-

bated topic (Hameroff & Penrose, 2014b, 2014c, 2014a; Rosa & Faber, 2004; Tegmark, 2000).

Id est, collapse of Ψ via “environmentally-induced Superselection” (Zurek, 2003). A large proportion of states in

the Hilbert space of a given quantum system are rendered unstable (decoherent) due to interactions with the

environment (thereby inducing collapse of the wavefunction) since every system is to a certain degree coupled

with the energetic state of its environment (entanglement between system and environment).

In a Hegelian fashion, Chalmers argues that “the thesis is materialism, the antithesis is dualism, and the

synthesis is panpsychism” (Chalmers, 2016).

Figure 1. Neuronal microtubules are composed of tubulin. The motor protein kinesin (pow-

ered by the hydrolysis of adenosine triphosphate, ATP) plays a central in vesicle transport

along the microtubule network (adapted from Stebbings, 2005).

References

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Philosophical Essays, (July 2012), 1–32.

Chalmers, D. (2016). Panpsychism and panprotopsychism. Panpsychism: Contemporary

Perspectives, (June 2011), 19–48.

https://doi.org/10.1093/acprof:oso/9780199359943.003.0002

Conde, C., & Cáceres, A. (2009). Microtubule assembly, organization and dynamics in

axons and dendrites. Nature Reviews Neuroscience. https://doi.org/10.1038/nrn2631

Fitzgibbon, S. P., Pope, K. J., MacKenzie, L., Clark, C. R., & Willoughby, J. O. (2004).

Cognitive tasks augment gamma EEG power. Clinical Neurophysiology, 115(8), 1802–

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of the universe? Trends in Cognitive Sciences, 2(4), 119–124.

https://doi.org/10.1016/S1364-6613(98)01157-7

Hameroff, S., & Penrose, R. (2014a). Consciousness in the universe: A review of the

'Orch OR' theory. Physics of Life Reviews, 11(1), 39–78.

https://doi.org/10.1016/j.plrev.2013.08.002

Hameroff, S., & Penrose, R. (2014b). Reply to criticism of the “Orch OR qubit” -

“Orchestrated objective reduction” is scientifically justified. Physics of Life Reviews.

https://doi.org/10.1016/j.plrev.2013.11.014

Hameroff, S., & Penrose, R. (2014c). Reply to seven commentaries on “Consciousness in

the universe: Review of the ‘Orch OR’ theory.” Physics of Life Reviews, 11(1), 94–100.

https://doi.org/10.1016/j.plrev.2013.11.013

Penrose, R., & Hameroff, S. (2011). Consciousness in the Universe: Neuroscience, Quantum

Space-Time Geometry and Orch OR Theory. Journal of Cosmology, 14, 1–28.

Rosa, L. P., & Faber, J. (2004). Quantum models of the mind: Are they compatible with

environment decoherence? Physical Review E - Statistical Physics, Plasmas, Fluids, and

Related Interdisciplinary Topics, 70(3), 6. https://doi.org/10.1103/PhysRevE.70.031902

Stebbings, H. (2005). Cell Motility. In Encyclopedia of Life Sciences. Chichester, UK: John

Wiley & Sons, Ltd. https://doi.org/10.1038/npg.els.0003967

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Review E - Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics,

61(4), 4194–4206. https://doi.org/10.1103/PhysRevE.61.4194

Vaidya, A., & Bilimoria, P. (2015). Advaita Vedanta and the Mind Extension Hypothesis:

Panpsychism and Perception. Journal of Consciousness Studies, 22(7–8), 201–225.

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Zurek, W. H. (2003). Decoherence, einselection, and the quantum origins of the classical.

Reviews of Modern Physics, 75(3), 715–775.

https://doi.org/10.1103/RevModPhys.75.715