general

I'm a clinical neurologist myself, and familiar with Damasio's work...there's no doubt he's a first rate behavioral neurologist, who's made many original contributions on both theoretical and clinical levels to neuroscience and neurology. I believe his particular breakdown of consciousness into several levels..."proto" "core" "autobiographical" and "extended"...to be both novel and supported by clinical evidence and intuition. It is inaccurate to say that Damasio equates consciousness with the reticular activating system. In fact, he conceives "core consciousness", the unadorned feeling of self, to be a network function including not only the RAS, but the intralaminar thalamic nuclei and cingulate and primary somatosensory cortex. I also disagree strongly with the reviewer who felt the ideas were largely redundant with previous philosophical attempts at explanations of consciousness. Though I agree the book is at times wordy and could use more detailed scientific backup in places, it is clearly aimed at a popular audience. I look forward to seeing his paradigm used in further neuroscientific research on consciousness, and I'm convinced it will be. This book is definitely on the right track, and one shouldn't hesitate to read it. I'd also note that the book is strongly endorsed by leading scientists and philosophers, such as Eric Kandel, David Hubel, and the Churchlands.

This is a fabulous book about the way that the brain interacts with the body, and with signals from the external world, to produce consciousness. That being said, there are long stretches of theorizing that could have been usefully broken up by more research -- laboratory or clinical; Pinker's How the Mind Words strikes a better combination. More seriously, I'm not convinced that Damasio achieves his objective: to explain consciousness. The closer he gets to that holy grail, the more he lapses into metaphors and appeals to poetry, a sure sign of trouble. Furthermore, to the extent that he sticks to the cognitive science lingo of mapping and images, I kept thinking that what he considers to be the essence of consciousness -- second-order images of the interaction of images of the world with images from the body -- could be replicated on a computer, without this producing consciousness in the sense that humans and (other) animals have it. While the book left me with a much-improved understanding of the biological supports of consciousness, an analysis of preconditions does not an explanation make.

Damasio breaks down into minute, qualitative descriptive detail how the boby/brain functions in humans, and ergo, de facto, many mammals. This book's strength is that Damasio backs up his claims regarding neural anatomy, physiology, and function with specific examples from comparative neuropathology. The book's weakness is that he goes on at length with qualitative descriptions for non-intuitive notions like how the body and brain function as a singular unit, and how emotions and feelings are integral along with body/brain physiology. I say this is the book's weakness because Damasio often bogs down and even tries to describe phenomena that are possibly ineffable, but these attempts at qualitative description are also one of the strengths of this book. This may seem contradictory, but possibly the book would have read differently if the author had stuck to purely quantitative case studies. However he did not, so we get through Damasio's several qualitative, alternate descriptions of singular phenomena an attempt to flesh out and make organic the dry clinical data. On the one hand the book could have been more concise without the extended descriptive sections, on the other hand the book possibly becomes richer and more meaningful because of them; this is up to the reader to decide.

Having said this, the book itself endeavors to demonstrate how consciousness emerges from gross neuroanatomy and physiology. In this Damasio is successful in using neuropathology to define terms such as: homeostasis, consciousness, language, mental images, neuronal maps, cathexis, and hedonic tone (although he does not use these two latter terms explicitly). In all honesty Damasio is very strict about defining his terms. Even though the author writes to a popular audience some knowledge of neuroanatomy and physiology is helpful in reading this book for maximum effect; although this book would be a good beginning for those interested in neurology. In General, the appendix, 'Notes on Mind and Brain,' should probably be read prior to reading the main body of text, especially if the reader is weak in basic neurology. In any event, Damasio is big on forming neologisms although he spends adequate time defining and explaining them. As a neurologist, he always couches his arguments in materialist, Darwinistic terms.

A good way to describe the structure of this often rambling, inchoate book, is to briefly compare it to Dr. Paul McLean's triune brain model. The triune brain posits the reptilian brain (brain stem) as primary, the mammal brain (thalamus, limbic, etc.) as secondary, and the primate brain (cortex) emerging evolutionarily later as tertiary. Damasio uses a similar foundation in positing the proto-self, the core self, and the autobiographical self (I told you there were a lot of neologisms), but he does so in a way that has them all hang together as a synchronous, functioning unit. The proto-self is rather the sense of homeostatic organism state, where the core self is the 'transcient but conscious reference to the individual organism in which events are happening' (to get a taste of Damasio's descriptive effluence), and the autobiographical self is the more cortical, temporal sense of self derived from transcendental yet highly efficacious ideas about past and future. It can all get pretty incoherent, but a complete reading of the book supplies numerous neural correlates which shore up the author's assertions.

In the end it is hard not to recommend this book because, in the reading of it, the author lights upon accurate though transitory descriptions of what it means to have a brain and be conscious. He places emotions and feelings (better see his definitions of these two terms) in their proper place in neural events. Indeed Damasio does well in defining a neural basis for epistemology [p. 130, 137, 138, 296, 305, 316] and idealism [p. 320, 322]. In closing Damasio admits that 'we cannot characterize yet all the biological phenomena that take place between (a) our current description of a neural pattern, at varied neural levels, and (b) our experience of the image that originated in the activity within the neural maps.' Indeed we may never be able accomplish such a correlation absolutely, but in the reading of a book such as this one, and say, Edelman's "A Universe of Consciousness," we see we are not very far off either.