A Quantum-Biological Review of the Penrose-Hameroff 'Orch OR' Theory of Consciousness: A Harmonious Symphony or Out-of-Tune Orchestra?

Abstract

My thesis investigates the feasibility of the Orch OR theory, developed by physicist Roger Penrose and anesthesiologist Stuart Hameroff, which claims that quantum computation in the brain could explain consciousness. Based on Penrose’s idea of objective reduction (OR) of a quantum superposition, Hameroff and Penrose developed the proposal that orchestrated OR (Orch OR) in neuronal microtubules could create conscious moments. In this thesis, I will lay out a critical analysis of Penrose’s and Hameroff’s argumentation, highlighting existing and original critique from the field of neurobiology. This detailed overview of the most important criticism will show that the Orch OR proposal lacks convincing experimental evidence, especially regarding the link between quantum computation in microtubules and neuronal activity. My thesis will contribute to the debate on consciousness by comparing the critical attitude of neurobiologists to the open-minded view of philosophers of mind. In my opinion, collaboration between philosophers and neuroscientists is crucial for bringing philosophical progress on the topic of consciousness. I will conclude this thesis by pointing out that even though the Orch OR proposal in its current form is not sufficiently developed to explain consciousness, this theory could still be of value to the field of consciousness studies in its pioneering role as one of the first respectable quantum theories of consciousness.