Orch OR | Stuart Hameroff, MD

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Orch OR

Consciousness and Orch OR

I became interested in consciousness as an undergraduate, and in medical school in the early 1970s worked in a cancer lab and studied mitotic cell division. The precise separation of chromosomes and formation of dividing daughter cells were performed by mitotic spindles and centrioles, composed of self-organizing protein polymers called microtubules. Fascinated by their apparent intelligence and purposeful behavior, I wondered whether the microtubule polymer lattice processed information as a molecular computer, to organize cellular activities. If so, could this be somehow relevant to consciousness?

Following medical school I trained in anesthesiology at the University of Arizona, mentored by the department founding chairman Burnell Brown. He convinced me the best way to understand consciousness was to understand how anesthetic gases selectively block it, sparing non-conscious brain activities. In my academic career I’ve researched anesthetic action, microtubules and consciousness, as well as high frequency jet ventilation, chronic pain therapies, neuromuscular blockade, brain monitoring during anesthesia and transcranial ultrasound brain therapy. With engineer and physicist colleagues I developed models of microtubule information processing at deeper, higher capacity levels within neurons, and in the 1980s challenged mainstream ideas in neuroscience and artificial intelligence (‘AI’).

Following an interest which began in medical school in the computational capacity of microtubules inside neurons, Dr. Hameroff proposed in the early 1980’s that microtubules functioned as molecular computers. Hameroff’s 1987 book Ultimate Computing suggested downloading consciousness into microtubule arrays.

In the mid-1990s Hameroff teamed with British physicist Sir Roger Penrose to develop the controversial theory of consciousness called “orchestrated objective reduction” – Orch OR theory – in which consciousness derives from quantum computations in microtubules inside brain neurons, quantum computations connected to the fine- scale structure of spacetime geometry. Dr. Hameroff has published five books and well over 100 research articles, and appeared in the film ‘What the Bleep do We Know?’ and numerous TV documentaries on the problem of consciousness including BBC, Discover Channel, History Channel, PBS, OWN, Huff Post Live and the film “What the Bleep?”

But one day someone said: “OK, there’s all this information processing in microtubules going on inside neurons. How would that explain consciousness?” I had to admit I didn’t know, but fortunately he suggested I read ‘The emperor’s new mind’ by Roger Penrose (1989), which I did.

In it, Roger proposed ‘objective reduction’, ‘OR’, self-collapse of quantum superposition due to spacetime geometry, as a solution for both the quantum measurement problem and the ‘hard problem’ of conscious experience. It was audacious and brilliant. He was suggesting a ‘quantum’ mechanism for consciousness connected to the fine scale structure of the universe, but needed a quantum computer in the brain able to modulate neuronal functions. To me, microtubules fit the bill perfectly, and Roger agreed when we met. In the mid 1990s we published the Penrose-Hameroff theory of ‘orchestrated objective reduction’ (‘Orch OR’) which suggests consciousness arises from quantum vibrations ‘orchestrated’ in microtubules inside brain neurons, orchestrated vibrations which are proposed to interfere, ‘collapse’ and resonate across scale, control neuronal firings, and generate consciousness.

Orch OR was viewed skeptically, as quantum technology requires extreme cold to avoid thermal decoherence. But evidence has now shown 1) functional quantum behavior in photosynthesis proteins in sunlight, 2) coherent vibrations in microtubules at ambient temperatures in a multiscale hierarchy spanning terahertz, gigahertz, megahertz, kilohertz and hertz frequencies, 3) anesthetic action on microtubules rather than membrane proteins.

Testing Orch OR

For Orch OR to be feasible, microtubules would need to sustain functional quantum states spatially and temporally. Microtubules are polymers of the protein tubulin, each of which has 86 ‘aromatic’ amino acid rings (tryptophan, phenylalanine and tyrosine) of delocalized ‘pi electron’ resonance clouds. These electron clouds form non-polar (water-aversive) regions inside tubulin which are friendly to quantum-optical effects like fluorescence, phosphorescence, van der Waals coupled dipole oscillations, delayed luminescence, and superradiance. These non-polar regions are also precisely where anesthetic gases bind and act by weak, quantum interactions to selectively block consciousness.

To test Orch OR we set out to 1) demonstrate quantum optical states in microtubules at physiological conditions. If demonstrated, we would then 2) test effects of general anesthetics upon the microtubule...