on April 27, 2004
ABSOLUTELY RECOMMENDABLE for anyone interested in how the brain works.
The clear exposure and expertise of the author(s) makes of this book an extremely enjoyable read.
Great for Neuroscience and Cognitive science students. With citations supporting every little detail exposed, it creates a library for future readings.
For non-scientists interested in the brain and mind this book should be quite easy to understand.
on April 22, 2004
Christof Koch takes the reader on a literal quest, starting where visual information enters at the eyes and proceeding as it is processed in successive layers of the brain, looking for the neural correlates of consciousness: neural activity corresponding in an explicit, easily understandable way, directly to our conscious percepts. Along the way we learn what is known (and what is still mysterious) about the various brain areas, neural organization, and information pathways, and about how this information has been gained. Understanding consciousness is a kind of holy grail, and the excitement of the author's personal chase rendered the book so gripping to me that I read it straight through.
Many readers will find the most interesting sections to be those in which Koch goes beyond his more sober scientific publications to speculate on the nature of qualia, our sensations such as pain or redness, as arising through evolution and corresponding to "meaning". Unfortunately, beyond a few evocative paragraphs, Koch does not address the nature of meaning. He also explicitly defers judgement on questions such as why qualia feel like anything at all to us and whether we have free will. I don't think he should be faulted for these omissions -- while these subjects are not beyond the scope of science, they may well be beyond the scope of neurobiology.
However, readers interested in the Quest for Consciousness will also enjoy What is Thought?, which brings ideas from computer science and other fields to bear on these questions. WIT? is organized around a computational theory of what meaning is and of how evolution discovers and exploits it. This theory suggests viewing the genome as source code that compiles into the brain as executable. Thus it is suggested that neurobiology is not the only or even the most straightforward path to understanding the mind: simple, understandable structure in source code often is blown up and obscured in the executable. What is Thought? analyzes computationally what it means to understand, how we understand, and what we can understand about understanding. Finally it offers a straightforward, principled theory of why qualia feel like something to us, and indeed why they feel like they do, as well analyzing in detail what free will is, how it arises, and what its limitations are.
The computational theories of What is Thought? unify relevant data from a variety of fields but the book discusses relatively little neuroscientific data. Its theories and approach will ultimately be confirmed or falsified as technologic progress continues: as gene expression data and brain imaging improve, as new psychophysics experiments are developed, for example probing qualia illusions in unnatural circumstances. On my reading, they are consistent with the data and most of the theories in Quest for Consciousness, but also there is considerable potential for integrating the data and approaches of the two books into further experimentation and understanding.