Wider Than the Sky: The Phenomenal Gift of Consciousness [Hardcover]

In this new book, Gerald Edelman continues his intellectual saga regarding the scientific study of consciousness. Both the Theory of Neuronal Group Selection (TNGS) and the Dynamic Core Hypothesis have been introduced in earlier books (Surprizingly, with alot more mathematical detail), but never had they been described with clarity and vividness as they were in this book. Examples, that the general reader can relate to, are given throughout the whole book.

Chapter One (The Mind of Man: Completing Darwin's Program) is an assertion by Dr. Edelman that any theory of consciousness should account for the phenomenon to have arisen in evolution by Natural Selection.

Chapter Two (Consciousness: The Remembered Present). This is a chapter in which Dr. Edelman talks about some properties of consciousness in light of William James' earlier descriptions. He ascribes privacy, differntiation and intergration to consciousness and stresses the fact that consciousness is a process not a "thing". For instance, on page 6 he says:
"... there are accounts that attribute conscoiuness specifically to nerve cells (or consciouness neurons) or to particular layers of the cortical mantle of the brain. The evidence, as we shall see, reaveals that the process of consciousness is a dynamic accomplishment of the distributed activities of population of neurons in many different areas of the brain."

Chapter Three (Elements of the Brain) is where Dr. Edelman briefly goes over the structural elements of the brain, describing neurons and their chemical and electrical based signaling systems along with diagrams. He also describes the next hierarchial system of networks and highlights three major neuroanatomical systems that are important for his Global theory of consciousness. Those are the thalamocortical system, cortical/subcortical polysynaptic loop systems (e.g. basal ganglia), and the ascending value system arising from nuclei in the brainstem. It is worth noting that this structural organization is in good agreement with Bernard Baar's Global Workspace model. Another point worth mentioning in this chapter is Edelman's view of synaptic plasticity in relation to memory. on page 21 he says, "Studies of the neural properties of the hippocampus provide important examples of some of the synaptic mechanisms underlying memory. One such mechanism, which should NOT be equated with memory itself, is the change in the strength, or efficacy, of hippocampal synapses that occur with certain patterns of neural stimuation."

Chapter Four (Neural Darwinism: A Global Brain Theory) is a superb chapter. Although, conceptually, TNGS has already been built in earlier books and publications, but it is now vividly described. Dr. Edelman highlight major differences between the working of the brain as a selectional biological systems and that of a Turing Machine. He discusses noise in biological systems, degeneracy, and reentrancy. Degeneracy in relation to Reentrant circuits is finally illustrated in a diagram.

Chapter Five (The Mechanism of Consciousness) is where Dr. Edleman talks about non-representational memory of biological systems (a difficult concept made simple). He also describes the emergence of primary consciousness On page 57 as " The ability to create a scene by such reentrant correlations between value-category memory--reflecting earlier categorizations--and similar or different perceptual categories is the basisfor the emergence of primary consciousness."

Chapter Six (Wider than the Sky: Qualia, Unity, and Complexity) discusses the aformetioned issues along with concepts like information exchange accross brain areas stressing the role of consciousess in them.

Chapter Seven (Conscoiusness and Causation: The Phenomenal Transform) discusses the place of consciousness in the physical world. Dr. Edelman introduces C and C' notions, and explains the logical impossibility of zombies (introduced by David Chalmers).

Chapter Eight (The conscious and the Nonconscious: Automaticity and Attention) discusses the role of consciousness in behavior, and the evolutionary advantage of having a conscious system over automatic (zombie) systems. Dr Edelman also discusses the role of basal ganglia in mechanisms of attention (which are strongly associated with conscious thought).

Chapter Nine (Higher-Order Consciousness and Representation) discusses the role of symbolic/semantic thought in the emergence of higher order consciousness. It also talks about the semantic problems with ascribing representation to neural states that could be observed from a third person perpective, and provides evidence that the neural correlates of consciousness (for a laboratory task at least) are distinct in different people.

Chapter Ten (Theory And Properties Of Consciousness) puts it all together. A superb chapter describing General, Information, and Subjective featres of conscious states in light of all the arguments made earlier. It is the intellectual climax of the book.

Chapter Eleven (Identity: The self, Mortality, And Value) and Chapter Twelve (MInd and Body: Some consequence) describe some scientific and philosopical consequences to the neurobiologic framework of consciousness the book makes. There are some really interesting thoughts regarding value and law.

Overall, this is a great book. The scientific american book review (which is shown on the book description page) is, in my opinion, very poor. If this book was made longer, discussed the ideas more, and showed more experimental evidence (and maybe more math in the Appendix), it would arguably be the best book on consciousness ever written.

The human brain consists of a hundred billion neurons that ultimately result in consciousness and self-awareness. It doesn't require much gray matter to appreciate the complexity of this process. In his fascinating study of this experience, Dr. Gerald M. Edelman attempts to answer the challenging question: How can the firing of neurons give rise to human sensations, thoughts and emotions (p. xii)? As a Nobel laureate, the Director of the Neurosciences Institute in La Jolla, and author of several important studies on consciousness, Dr. Edelman certainly has the credentials. He recognizes his subject is a challenging one, and has written WIDER THAN THE SKY for "the general reader" (with no background in neurobiology, like me), who is willing to expend "a concentrated effort" to understand the subject, promising readers who stick with him on his trip through the human brain a "deeper insight into issues that are the center of human concern" (p.xi).

In his short, 148-page book (exclusive of the glossary and index), Dr. Edelman first considers global brain theory encompassing evolution, development, and function of the most complex of human organs. He basically proposes that in the transition between reptiles and birds and reptiles and mammal, a new reciprocal connectivity evolved in the thalamocortical system of the brain (p. 54), and that consciousness then emerged from increasingly complex and integrated neuronal groups. In the end, WIDER THAN THE SKY provides readers with a concise, scientific explanation of consciousness unique to humans.

G. Merritt

A self referential jargon filled text which fails to appeal to the lay reader and makes several shockingly poor assumptions.

Instead read On Intelligence by Jeff Hawkins which carefully constructs a theory for the central functions of the cortex, namely prediction and construction of invariant representations of the world.

The fundamental assumption of Edelman's book is that consciousness is a unitary construct, this is just terribly terribly wrong. The mind is best described by what it cannot perceive or intentionally ignores. This is antithetical to Edelman's conjecture that if we look hard enough we will be able to see the threads that make up the cloth of consciousness. The great power of the mind is to ignore the fact that there are huge alterations, moment to moment, between what areas of the brain are actively contributing to consciousness, and *we don't notice.*

The problem with any book which seeks a consciousness down approach to understanding the mind is that introspection and self reported description of how the brain operates are very poor guides for neuroanatomy. We feel like there is an *I* viewing the world, but really there are many many different portions of the brain which are watching each other portion of the brain at any given moment. It is the harmony of these voices which produces a sense of continuous self, even as we shift among them, and the discord which creates phenomenon like dual-selves in split brain patients, voices heard by Schizophrenics, etc.

I have deep respect for Edelman as a scientist, but I am used to the quality of lay science writing provided by New Scientist, Scientific American, and writers like Watson and Feynman. In this realm he simply doesn't measure up. His journal papers on the other hand, are, of course, first rate.