Orchestrated Objective Reduction - The Creation of The Orch-OR Model

The Creation of The Orch-OR Model

When he wrote his first consciousness book, The Emperor's New Mind in 1989, Penrose lacked a detailed proposal for how such quantum processes could be implemented in the brain. Subsequently, Hameroff read The Emperor's New Mind and suggested to Penrose that certain structures within brain cells (neurons) were suitable candidate sites for quantum processing and ultimately for consciousness. The Orch-OR theory arose from the cooperation of these two scientists, and was developed in Penrose's second consciousness book Shadows of the Mind (1994).

Hameroff's contribution to the theory derived from studying brain cells (neurons). His interest centered on the cytoskeleton, which provides an internal supportive structure for neurons, and particularly on the microtubules, which are the most important component of the cytoskeleton. As neuroscience has progressed, the role of the cytoskeleton and microtubules has assumed greater importance. In addition to providing a supportive structure for the cell, the known functions of the microtubules include transport of molecules including neurotransmitter molecules bound for the synapses, and control of the cell's movement, growth and shape.

Hameroff proposed that microtubules were suitable candidates to support quantum processing. Microtubules are made up of tubulin protein subunits. The tubulin protein dimers of the microtubules have hydrophobic pockets which might contain delocalized π electrons. Tubulin has other smaller non-polar regions, for example 8 tryptophans per tubulin, which contain π electron-rich indole rings distributed throughout tubulin with separations of roughly 2 nm. Hameroff claims that this is close enough for the tubulin π electrons to become quantum entangled. Quantum entanglement is a state in which quantum particles can alter one another's quantum-mechanical state instantaneously and at any distance, in a way which would not be possible if they were macroscopic objects obeying the laws of classical physics.

In the case of the electrons in the tubulin subunits of the microtubules, Hameroff has recently suggested that these are part of a Frohlich condensate, which is a coherent oscillation of dipolar molecules. This oscillation was originally proposed to be a Bose-Einstein condensate, but in the most recent version of the theory Hameroff favours a synchronous oscillation of the electrons. Hameroff suggests that through a feature of this kind, quantum activity, which is usually at a very tiny scale, could be boosted to be a large scale influence in the brain.

Hameroff has proposed that condensates in microtubules in one neuron can link with microtubule condensates in other neurons and glial cells via gap junctions. In addition to the synaptic connections between brain cells, gap junctions are a different category of connections, where the gap between the cells is sufficiently small for quantum objects to cross it by means of a process known as quantum tunneling. Hameroff proposes that this tunneling allows a quantum object to extend across a large area of the brain as a single quantum object.

He further postulates that the action of this large-scale quantum feature is the source of the gamma synchronization observed in the brain, and viewed as a neural correlate of consciousness. In support of the much less controversial theory that gap junctions are related to the gamma oscillation, Hameroff quotes a number of studies from recent years.

The Orch-OR theory combines Penrose's hypothesis with respect to the Gödel theorem with Hameroff's hypothesis with respect to microtubules. Together, Penrose and Hameroff have proposed that when condensates in the brain undergo an objective reduction of their wave function, that collapse connects to non-computational decision taking/experience embedded in the geometry of fundamental spacetime.

The theory further proposes that the microtubules both influence and are influenced by the conventional activity at the synapses between neurons. The Orch in Orch-OR stands for orchestrated to give the full name of the theory Orchestrated Objective Reduction. Orchestration refers to the hypothetical process by which connective proteins, known as microtubule-associated proteins (MAPs) influence or orchestrate the quantum processing of the microtubules.

Further to this, in 1998, Hameroff made 20 testable predictions related to his proposal. However, some of these proposals have been falsified. The proposed predominance of 'A' lattice microtubules, more suitable for information processing, has been falsified by, which showed that all in vivo microtubules have a 'B' lattice and a seam. The suggestion of coherent photons has been falsified, as has the existence of gap junctions between neurons and glial cells, and the proposal that photons do not decohere in the retina.