Penrose and Hameroff's theory about microtubules is certainly science not pseudoscience. It is a specific theory with falsifiable predictions.
In the absence of a definition of consciousness, perhaps the only validation would be evidence that general anaesthetics take effect in the microtubules (Hameroff is an anaesthesiologist).
It might not be possible to show that macroscopic quantum effects are required, or that consciousness is more powerful than an algorithmic computer (Turing Machine) - two of Penrose's related speculations.
Another of Penrose's claims is that gravitational divergences collapse the quantum wavefunction. This is logically separate from, but is often linked with, the conscious perception issue, as presented in their Orchestrated Objective Reduction theory (ORR):
The latter gravitational claim is being tested independently from brains, using conventional QM experiments in the presence of large masses. The precision to resolve the question is within reach.
In the absence of a definition of consciousness, perhaps the only validation would be evidence that general anaesthetics take effect in the microtubules (Hameroff is an anaesthesiologist).
It might not be possible to show that macroscopic quantum effects are required, or that consciousness is more powerful than an algorithmic computer (Turing Machine) - two of Penrose's related speculations.
Another of Penrose's claims is that gravitational divergences collapse the quantum wavefunction. This is logically separate from, but is often linked with, the conscious perception issue, as presented in their Orchestrated Objective Reduction theory (ORR):
https://en.m.wikipedia.org/wiki/Orchestrated_objective_reduc...
The latter gravitational claim is being tested independently from brains, using conventional QM experiments in the presence of large masses. The precision to resolve the question is within reach.
Definitely science.