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49 of 49 people found the following review helpful:
4.0 out of 5 stars
Novel ideas; thought-provoking, September 15, 2001
This is another in a spate of recent popular books by leading neuroscientists attempting to explain consciousness and the mind. They are a bit like the fable of the blind men and the elephant. Damasio, a neurologist, (The Feeling of What Happens) takes a neurological perspective; Freeman (How Brains Make up Their Minds)uses a systems approach derived from his research into olfaction; Edelman (A Universe of Consciousness)takes more of a neuroanatomical approach (massive reentrant systems)and in this book Llinas works from his background in cellular physiology up from the level of the single cell. Llinas' book is the best referenced of the above, and he really has some good insights. His discussion on qualia as a sensory "fixed action pattern," analogous to motor FAPs, I thought particularly original. I also liked his idea of the origin of the self as a brain representation of the body, which has profound implications, for it implies virtually all animals have at least a primitive "sense of self." Although the link between cellular physiology and higher levels of nervous system organization is not (understandably) well bridged in the book, all in all, I think Llinas describes a good chunk of the elephant...definitely worthwhile reading.
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35 of 36 people found the following review helpful:
5.0 out of 5 stars
worth the attentional investment, November 17, 2001
Llinas cuts to the chase of consciousness in a quick and original way. Initially, his tack may strike the nonspecialist reader as narrowly technical, and for good reason: he is a benchworking neurophysiologist. On re-reading, his big picture comes into view, and it is utterly convincing without being exclusive, characteristic of the inventive scientist.The theme of this book is an explanation (not just description) of consciousness as evolutionarily generated from the motor system. This is counterintuitive: we're used to hearing that consciousness emanates from the processing of sensory/perceptual data, a presumption so widely accepted that it seems incontrovertible. Thus, Linas' standing as a recognized expert allows him to cite basic experimental findings, then bring along other ideas at a more speculative (yet still scientific) stage, to build a thesis of substantial generality. In fact, given the unitary quality of subjective experience, such generality is requisite. So what is the thesis? That the centralization of motricity is constituitive of consciousness. Centralization (`cephalization') takes the intrinsic coupling and coordination of muscular movement and embeds it in progressively higher levels of the nervous system. Again, this might first seem unexciting; but Llinas underpins his ideas with a cogency which few others could muster, then guides us up the neuraxis to higher brain levels. He starts with a typically astute interpretation: essential tremor as evidence of a pulsatile control system operating at the tactical level, coping with a computationally intractable confusion of sensory data, whose control any mobile life form must develop. Primitive muscular coordination is then shown to require neural coordination at a higher evolutionary level. The command system penultimately culminates in the basal ganglia, the generator of `fixed action (stereotyped) patterns' of behavior; and, from there, goes to thalamocortical and limbic circuitry where such FAP's are now strategic, and ultimately voluntary. If one describes the transformation of sensory to motor coordinates as occuring in a state space (called vectorial coordinate space) it's then possible to give a principled account of consciousness as that virtual space which describes those transformations in a broader context of social and emotional dimensions. Put more practically, consciousness emerges unforced as a survival necessity, without which we'd never be able to decide whether to whistle or urinate as a predator (one's boss) enters the men's room. In truth, there are gaps: Llinas' original papers lack the sweep (other than oscilloscopic) which would give detailed rather than general support to the broader issues here addressed. The 40 Hz hypothesis rests upon MEG studies which one is hard-pressed to coordinate with `conventional' fMRI and PET imaging, let alone individual neurons. But this is a minor caveat on a playing field where few contributors even agree on the rules of engagement. An investment of attention to the thesis of this book proves surprisingly rewarding.
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37 of 39 people found the following review helpful:
5.0 out of 5 stars
Very worthwhile, May 20, 2002
The author presents quite a plausible theory of mind, based on his work as a neuroscientist. I suspect Llinas is very much on the right track to illuminating the physical basis of consciousness. Building chapter-by-chapter simultaneously on the apparent evolutionary development from the simplest neuronal system to the centralized brain, and on the results of brain scans and other experiments, Llinas brings us calmly and reasonably to the resultant human mind of today. For Llinas, consciousness is the synchronized 40Hz firing of regions of the cortex over time. That is, consciousness is not just a given pattern of firing in 3-space, but is a 4-space relation. That additional dimension of time multiplies enormously the potential number of brain patterns that could occur in an individual. But it also makes the topic that much harder to study. The writing feels like it has been written by someone who knows alot: there are many points where conceptual connections are not made entirely explicit (because it probably seemed so self-evident to Llinas) and the reader must fill in those gaps. Also, some of his non-neurologic language is quite technical: the description of the "self" as a calculated eigenvector, or the "vortex" which is essentially an attractor (as known in mathematics), that can make Llinas sound like a cold, hard-nosed scientist. However, Llinas is refreshingly 'human'. For him, it is quite reasonable to assume (as a common consequence of evolution and similarity of brain structure) that many other species have forms of consciousness. Indeed, he devotes an entire chapter to qualia, and contends that qualia exist as essential brain feature, not only for humans but for cats and dogs and most other animals with brains of the same evolutionary genre (and that even in the case of invertebrate (octopus) brains he argues that the burden of proof is on those who would deny qualia). One caveat: be aware that Llinas does not explicitly delineate between accepted facts and his theory - the book flows as one whole. It is not intented as deception. As he says in the preface "This book presents a personal view of neuroscience...".
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