David A. Berry 2006-09-07
2 of 2 people found the following review helpful:
While you may have read books that similarly describe genes and brain development, you will not find one that presents a better, more comprehensive or concise explanation. Marcus offers a short overview of current trends in genetics, neurology, microbiology, linguistics and psychology as well as presenting some of the most intriguing contemporary philosophical discussions. Through this book Marcus presents the hard-science arguments that are now shaping main-stream views about genetics and brain development without sensationalizing, overly speculating, or including entertaining personal anecdotes and diversions - common problems in popular science books about the brain.
Marcus begins by explaining that genes do not offer a plan for the body and then goes on to show how our brains develop through a combination of genetic and environmental influence. He supports his arguments with solid experimental examples that contradict many popular misconceptions, providing a better understand of mainstream scientific views. Brains are flexible and changing Marcus emphasizes. Parts of the brain are associated with specific functions and brain organization is greatly shaped by experience. This information about brain structure and function is unavoidably gained through animal experiments. While Marcus does not go into much detail, some experiments imply gruesome procedures that might upset some readers.
Some scientists "are right that significant parts of the brain are organized even without experience, and their opponents are right to emphasize that the structure of the brain is exquisitely sensitive to experience." (p 45). It is as if to say that brain development depends 100% on nature (genetics) and 100% on nurture (experiences). For Marcus this leads to the integrated relationship of being "prewired," but not necessarily "hardwired."
It is now accepted that genes are "...not a blueprint, but rather an enormous autonomous library of the instructions contained within its genome. Each gene does double duty, specifying both a recipe for a protein and a set of regulatory conditions for when and where it should be built. "By tying development to relative rather than absolute cues, evolution has provided us with a handbook of self-assembly both stunningly flexible and sublimely powerful.... From the perspective of a given cell, it doesn't matter where that signal comes from." (p 97) The independent nature of cells allows a great deal of influence from both genes and external influences - either from other cells or from the external environment in the form of stress, nourishment or sensory input. "Experience itself can modify the expression of genes." (p 98) Even so, not all genes can be influenced by experience, and not all experiences have the ability to change gene expression.
What is also remarkable is that "Virtually every gene in a mouse genome -- and many in the genome of a fruit fly -- has some sort of counterpart in the human genome." (p 79) Thus, the full range of highly unique structures and functions of the brain are closely related to all other living systems. Marcus goes on to explain the differences and similarities between chimpanzees and humans - which is exceptionally well presented.
Marcus ends his thesis arguing that the processes that govern the growth and regulation of the body are at work in the brain, and idea that runs contrary to many theories about the brain. We are at the verge of understanding much about how genes are involved in human development, and this will give us the opportunity to tinker with the processes, and Marcus speculates about some of the problems that we may face in the future. And, in a particularly honest note, Marcus makes it clear that our understanding of genetics and the brain is just beginning - thus the birth of the brain refers to our neonatal understanding of what is inside our heads.
The Birth of the Mind was published in 2004, it still is up to date. If anything, some of the more speculative concepts are now more experimentally supported. As a general introduction I believe it will stand as the best book of its kind for several more years.
Criticism
There is little to take issue with, but it should be understood that this book is a very short introduction (only 190 pages of text - 50 pages of notes and reference). Marcus' extremely concise and economical style puts a lot of information in a very few pages.
While Marcus works to dispel misconceptions, the best way to do so is to get a grasp of the general knowledge and common insights found within the various scientific fields. Other good comprehensive popular science books about the mind and brain include the works of William Calvin or Oliver Sacks. For a more philosophical (and controversial) view of genetics and the mind, try any of the many books by Steven Pinker, Daniel Dennett, Richard Dawkins or even Steven Jay Gould. For more in depth science that is relatively accessible to the popular science reader start a search on Amazon beginning with these books: "Synaptic Self," by Joseph LeDoux is unparalleled overview of the recent history and current state of neuroscience and psychology; "The Art Of Genes," by Enrico Coen, is very accessible and offers more advanced look at genetics; "The Human Genome" is short and very accessible summary of the human genome project as covered by Nature Magazine - including an appendix of scientific papers. But I still recommend beginning with The Birth of the Mind.
Readability rating 10 of 10
Rarely have I found a writer of entry level science who presents such a stunningly well researched work. Marcus is certainly one of the best scientific writers today.
Research Rating 9 of 10
The quality of the bibliography is impeccable and there are few secondary sources. Many of the hundreds of papers cited are not available on the internet or easily accessible outside of an academic setting. My only complaint is that the notes are abbreviated (page numbers are not included). For articles this is fine, but it is a concern for book citations - thus a rating of 9 instead of a 10. Since there are few book citations and most of these references concern generally accepted knowledge, this is not a big problem, but prevents me from categorizing this as a scholarly work. The 50 page appendix includes notes, full biography, subject index and name index. Marcus distils complex ideas into simple statements that are a great source for quotes. Having checked many of his references, I find that this is one of the few popular science books that I would reliably use as a secondary source - and occasionally as a primary source based on Marcus' expertise in his field and his overall description of the state of scientific thought.
