I wonder if his believing in these looney ideas are related to his psychedelic usage:
https://www.theatlantic.com/health/a...ticity/672910/

The thing is, all those changes aren’t necessarily all good. Neuroplasticity just means that your brain—and your mind—is put into a state where it is more easily influenced. The effect is a bit like putting a glass vase back into the kiln, which makes it pliable and easy to reshape. Of course you can make the vase more functional and beautiful, but you might also turn it into a mess. Above all else, psychedelics make us exquisitely impressionable, thanks to their speed of action and magnitude of effect, though their ultimate effect is still heavily dependent on context and influence.