Jeffrey Satinover

This is a dazzling and thorough review of how quantum effects could plausibly be behind human intelligence and consciousness. Despite being a mere 242 pages ( not including the index and references) the text is very dense, and this book does justice to a wide range of science, from computer science topics such as Hopfield nets, logical functions, and parallel processing, biology such as protein folding, microtubule anatomy, and neurons, to quantum mechanics, chaos science, and strange attractors. Though he is never overly heavy on maths or technical things, I never felt as if I was being cheated, (some popular science books try to pull the wool over the readers eyes), with some more in depth bits being included in an appendix where necessary. I think it helps that I am familiar with all the fields covered, chaos, quantum mechanics, and the biology, but someone not read in the fields could still get a lot out of this book, it would just take a lot longer to get through, as it is absolutely packed with information, that might require a bit of thought to understand, but it has plenty of illustrations too, which will help.
The goal of this book is to find a niche in the physiology of the brain where quantum mechanics can fit in and play a role in creating intelligence. While he dismisses Penrose and the ideas in his two books, he manages to invoke microtubules anyway, and quantum effects in them specifically, a lot more convincingly than their previous proponent did. He maybe gets carried away a bit in places, calling proteins "quantum computers", which they are certainly not, but that is not the case that is put forward here, so it is alright, and that particular description is just the author's enthusiasm getting the better of him. His aim here isn't to prove that proteins on their own compute anything in the brain though, but that they are the fundamental element, in the same way in which a segment of wire which makes up a transistor is, that several lengths of microtubules may perform a similar function as a transistor. These in turn build up a small scale adaptive neural net, below the level of the nueron, and that this, along with the feedback that occurs between neurons, makes up a multi tiered adaptive system of computation, (he also showed that computer systems wired "randomly", in a similar way, can "learn"). He doesn't invoke large scale coherence as Penrose does, which makes it all the more compelling, as decoherance on such scales surely occurs, but instead quantum effects provide the variation in initial conditions needed to create the sort of chaos in which patterns ( eg. Poincare recurrences) can emerge on higher scales, which is not possible to the same degree, by scales of magnitude, in purely mechanical, non chaotic, Newtonian systems. I may not have explained this point convincingly, and I hope I have not spoiled the book by giving away too much of its content, but this is the best book I have read on the topic, and the best popular science book, (if it counts for that, having only 53 copies on here, a shame), that I have read in ages, and it is convincing. For those left with a dry mouth after reading Penrose's books, thirsty for a proper quantum explanation of intelligence, this is what you need. For those not having read those books, you probably shouldn't, unless you have particular fondess for in-depth physics, (them being around twice as long, and ten times harder), read this instead, it would be interesting from the sheer variety of topics covered, were it not interesting from the profound implications of the whole anyway.… (més)