Customer Reviews

The Birth of the Mind: How a Tiny Number of Genes Creates The Complexities of Human Thought

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It's a great pleasure to be able to highly recommend this book. I was suspicious of it because of the hype sent from the publisher, and the extremely broad topic covered for a science book, but it turns out that this is really good science writing. Gary Marcus certainly knows his stuff and has a distinctive talent for making complex things crystal clear. More, he has an infectious positive enthusiasm for scientific exploration.

With most popular science books about the human mind, the author tends to allow the material to be organized by their political and moral thinking. By that I mean the way the author thinks about human reason, autonomy, free will, and the essential nature of humans in general. So we most often have authors interpreting scientific data to show how the mind is: hardwired (or flexibly changing during our lives); highly specialized (or a general purpose problem-solver), built from adapted computational modules (or is essentially a useful artifact or "spandrel").

Each of these different ways of selecting and interpreting the data reveals a different way of thinking about ourselves. A hardwired, specialized, modular brain gives a very different way of thinking about ourselves than does an autonomous reasoning agent, and the implications for morality and for politics are profound. While cognitive science and biology are our greatest allies in the physical understanding of the world, when we try to rely on science to understand ourselves, we have been forced to speculate and extrapolate from them heavily in trying to get an accurate picture of humanity.

I bring this up to illustrate why Gary Marcus' "Birth of the Mind" is such a notable book. Somehow he manages to steer a course between the jagged rocks of innateness, the whirlpools of environmental determinism, and even the usual awkward compromises. Marcus celebrates the triumph of interactionism (genes plus environments) not by simply claming it to be true but by explaining exactly what it means and what it tells us. This is not a speculation about how genes and minds might be related; it is a carefully built skeleton of the conceptual bridge between the two. "Nature and Nurture" are not waved away here but deeply engaged. "Nature" here is not a collection of guesses about how we acted in the stone age and the challenges we faced in our evolutionary history, but an exposition of cellular biology and the way genes guide the construction of minds as a direct consequence of how they construct bodies.

This is a wonderful change from the polemics we find too often in books discussing research in genetics, evolution, and human behavior. Marcus isn't entering into one side of the technical debates on human nature here as we find in much of the popular sociobiology literature and popular behavior genetics literature. He isn't arguing about whether the mind is modular or whether it is a product of evolution. Nor does he argue about whether we have a soul or free will. As his title implies he is rightly more concerned about specifically HOW the mind arises, and this in itself hints at useful answers to the thornier questions. The tone of this book is simply that of shedding much needed light on the entrance to a long path to growing scientific knowledge of ourselves. Marcus appreciates both what we know and what we don't yet know about the mind, and that's an extremely valuable quality for writing about such a complex topic.

The spirit here is similar to that of Matt Ridley's recent book on nature and nurture. It is based on the emerging technical consensus that genes are central players in virtually all processes in living things, yet that genomes are not blueprints but self-regulating recipes. A relatively tiny number of genes is able to guide the development of brains consisting of an enormous number of neurons, and miniscule changes in the genome can produce dramatic changes in the outcome. Yet people with the identical genome have neither identical brains nor identical minds.

The solution to this dilemma is the centerpiece of the book, and it is answered by the way the genes work. They act as recipes, but as self-regulating recipes. This, Marcus explains, is the answer to the two great paradoxes of the mind: (1) a relatively small number of genes can reliably guide the self-construction of such complex multi-cellular organisms, and (2) the body is elaborately structured by genetic information yet still so flexible to environmental influences during development.

These are important and difficult questions that have great implications for our lives, so it is admirable that Marcus has addressed them without any obvious political axe to grind regarding human nature.

The book starts off introducing the hard questions: the surprising ratio of genes to cells, and the confusing mixture of stable and flexible developmental outcomes.

It then describes how we come out of the womb not with empty or fully formed minds, but as well-prepared learning machines with amazing and previously mostly unsuspected talents for observing and remembering in particular ways. The distinction between a brain that is "hardwired" and one that is "prewired" is the next topic. The brain has a definite structure, but one that is built for flexible change. Even identical twins, who share exactly the same genes, have different brain structure. When the crucial concept of the self-regulating genetic recipe is introduced, we see how the brain is built in exactly the same way as the rest of the body.

Next we see how genes guide the way neuronal connections are laid down: both how the brain is wired and how its structure is revised over time.

There is a single chapter focusing on human evolution, particularly on our capacity for language. Language has long been the classic example of a "modular" ability, but Marcus takes a different slant here, genetic rather than sociobiological. The evolutionary origin of language is used to show specifically how a small number of genes can have huge evolutionary consequences.

Although I found The Birth of the Mind by Gary Marcus to be a very well written book, I don't think that the author has added anything significantly new. Anyone who has read Penrose, Pinker or Dawkins is pretty much aware of the theory of mind as emergent property of brain function. Anyone who has kept abreast of research in genetics is aware that most of what we are as biological beings is dictated by our DNA. That the brain and the mind are part of that is hardly a surprise either. Of Dr. Marcus's illustrations of physical and cognitive dysfunction drawn from neurology and neurophysiology, few were new and most have been discussed in far greater detail in other volumes, the best known probably being Oliver Sac's The Man Who Mistook His Wife for a Hat.
What the author does do is put all of the most recent work together in a very cogent and readable manner for the average reader on the subject. His friendly, chatty writing style makes the subject very accessible. A youthful Associate Professor in the department of psychology at NYU, with a primary research focus in the brain and the mind in cognitive psychology, he is well placed to pull recent and germane literature together. For anyone who has read very little about the topic but who wishes to get a well rounded idea of the subject, this is a good place to start. It's current and well written even if the conclusions are not especially new.
For THOSE WRITING TERM PAPERS in psychology, history of science,or philosophy, this book might provide you with a large, very current collection of sources from which to begin your own literature search. Most of them come from 1995-2002. Among the list of periodicals are journals like the American Journal of Human Genetics, Brain Research, Cognition, Journal of Comparative Neurology, Journal of Neurobiological Science, Nature, the Proceedings of the National Academy of Science USA, and Science. Some of these, like Science and Nature, will be readily available in most college libraries and even some local public libraries, while others will only be available at large university, especially those associated with medical schools.

Marcus says, "From a mind's-eye view, brains may seem awfully special, but from a gene's-eye view, brains are just one more elaborate configuration of proteins."

This book is a compilation of very recent research about how the brain as an organ puts itself together. This process is not unlike the process for any other organ, but results in a product that is highly malleable and ripe for environmental adjustment. The book has been explained very adequately by many reviewers, so I will mainly try to provide you with some representative quotes and add only a few comments.

About Nature vs. Nurture:

"The nativists 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."

" At the core of our story has been a tension between the evidence that the brain can - like the body - assemble itself without much help from the outside world, and the evidence that little about the brain's initial structure is rigidly cast in stone.....To an earlier generation of scholars, the evidence for innateness and the evidence for flexibility seemed almost irreconcilable. Most scholars simply focused their attention on the stream of evidence they were more impressed with....Both sides have their points. The brain is capable of awesome feats of self-organization - and equally impressive feats of experience driven reorganization. But the seeming tension between the two is more apparent than real: Self-organization and re-organization are two sides of the same coin, each the product of the staggering amount of co-ordinated suites of autonomous yet highly communicative genes."

The above non-debate (to a hard science person) is well-covered, but the jist of the book is more about how the pre-wiring occurs, relying occasionally on computer science analogies:

"Each gene acts like a single line in a computer program."

"As soon as the IF part of the gene's IF-THEN rule is satisfied, the process of translating the template part of the gene into it's corresponding protein commences."

"With one more trick - regulatory proteins - that control the expression of other genes - nature is able to tie the whole genetic system together, allowing gangs of otherwise unruly free-agent genes to come together in exquisite harmony."

"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. Taken together, suites of these IF-THEN genes give cells the power to act as parts of complicated improvisational orchestras."

How do the "billions of neurons in your brain" develop "trillions of connections between them." There is a well done scientific description given, but I also like his caricature description: "Even in a simple organism like a worm, the mechanics of (neuron) migration are so complicated they could have been borrowed from one of John Madden's playbooks. Cell number 1 goes right, number 2 goes left, and cell 3 goes long for a pass."

About language development:

" If language came onto the scene relatively quickly by evolutionary standards, it is because much of the genetic toolkit for building complex cognition was already in place."

"To understand the origin of language will be to understand how a relatively small set of new genes coordinates the actions of a much larger set or pre-existing genes."

"If language arose de novo, it would, I suspect, have to go through a long series of gradual steps, but if language arose by a novel combination of existing elements - such as neural structures for memory, the automatization of repeated actions, and social cognition - it is possible that it could have developed relatively quickly."

"A language module may depend on a few dozen or a few hundred evolutionarily novel genes, but it is likely to depend heavily on genes - or duplications of pre-existing genes - that are involved in the construction of other cognitive systems, such as the motor control system, which coordinates muscular action, or the cognitive systems that plan complex events."

There is lots more, including an appendix on methods for reading the genome, but I'll close with this quote from the final chapter: "In the coming decades, we will all - collectively , as a society - need to decide what we think about biotechnology and what applications we are and are not willing to allow. The debates we have now, about cloning and stem cell research, pale in comparison to debates we are likely to encounter as the technology for manipulating genes advances."

About a personal item:

When I was in school, I decided that I needed to study a concept an arbitrary number of times (say, 5 times), maybe from the different points of view of several scientific disciplines, in order to really learn it. I guessed that synaptic and neuronal pathways could be built up like bicep muscles. Marcus covers this and calls it "synaptic strengthening," along with a lengthy explanation that "More than a hundred different molecules may be involved, and there are at least 15 distinct steps in the process."

I highly recommend this excellent book.

I very much enjoyed and learned from this new and innovative book, Birth of the Mind by Dr. Gary Marcus. Still, before I could write my own review I came across a professional review in one of Britain's most distinguished journals, Nature Neuroscience. I present it instead:

"About half of the estimated 30,000-odd genes in the human genome are expressed in the brain. Among these genes is hidden the explanation for our unique human cognitive abilities, and for many of the differences between individual people. Developmental neurobiology is the essential bridge for connecting genome to behavior, but despite its obvious importance, there has not yet been a popular book devoted to this subject.

"The Birth of the Mind is an ambitious attempt to fill this gap. The author, Gary Marcus, is a cognitive scientist, but he has learned a lot about developmental neurobiology and has written a concise and very readable introduction to the field. By drawing on related disciplines such as genetics, cognitive science and evolution, he provides an overview of how the interaction between genome and environment gives rise to the human brain and by extension the human mind.

"Marcus gives as clear an account as I have ever seen of the nature versus nurture 'debate' In fact, most biologists no longer regard this as a debate (genes and environment are both important), and the fact that it is still perceived as such by the public may reflect the lack of clear popular account, which this book now provides.

"He also dispels a more recent myth, namely that there is a ~gene shortage™ that precludes genes from encoding complex behaviors. It is admittedly surprising that we have only 30,000 genes but 100 billion neurons, particularly given that the nematode C. elegans has nearly as many genes yet only 302 neurons. But as Marcus makes clear, genes are complex individually and give rise to even greater complexity by acting in combination; moreover, the truth is that we have no basis for surprise, absent a theory to explain how many genes are needed for a given degree of biological complexity"

"Einstein famously advised that everything should be made as simple as
possible, but no simpler. Marcus takes this to heart, and his book contains
many simplifications but few misrepresentations.

"... enjoyable to read [and written] with a light touch .... I have no
hesitation recommending it to students, scientists from other disciplines, or lay readers wanting to learn something about this fascinating and fast-developing field."

[Nature Neuroscience, April 2004, at p. 117, by Charles Jennings, Executive
Editor of the Nature Research Journals.]

If you are among those still arguing the "nature versus nurture" debate has been resolved, visit an English Lit class. The humanities continue skirting the notion that genes play a role in our mental life. It challenges our ideal of "free will". Marcus, in this matchless survey, argues that "what's good for the body is good for the mind". And few dispute that genes build bodies. The mind, like the body, has deep evolutionary roots. Even the simple organisms inhabiting the planet with us today show how brains develop. Increased complexity of body is reflected in brain structure. And the mind, he reminds us, resides in the brain.

Marcus explains his notion with a wealth of research, most of it very recent. He explains how similar our brain structure is to that of other animals and what that implies for behaviour. The mechanism of building brains is common to all animal life, even when the final product varies. Genes transmit signals - "recipes" - of structure and function for all parts of the body. Brains, he continually reminds us, are not that different from livers. Neurons proceed from points of origin, finding appropriate areas to reside and assume functional duties. From origin to operation they show flexibility and adaptability. In this, Marcus argues, it's clear the brain is no different than any other organ.

It is our brain's interaction with the rest of the body that sets us somewhat apart from the other animals. Language, the element we hold so dear in protecting our unique status, is given a thorough examination in this book. There are no "language genes", Marcus stresses, but there are identified genes, notably FOXP2, known to impact speech ability. He explains that looking for "genes for" something is futile. Genes interact in too convoluted a manner to expect simple associations between a few nucleotides and something as complicated as speech.

Marcus offers a novel term to counter those railing against the strawman "genetic determinism". Having explained how evolution has led to building brains, he declares them "prewired" but not "hardwired". "Prewired" means that basic functions are spelled out biologically, but don't limit our interaction with our environments. All brains permit flexibility by neurons interacting with each other as conditions vary. We can learn because we are prewired to learn. However, we've only begun the research where our brains are concerned.

Marcus presents this trove of information with amazing clarity. His topics aren't simple mechanisms or ideas, yet he conveys it all with graceful logic. He avoids "dumbing down" the science, yet nothing is lost in his presentation. His theme and supporting examples, buttressed by a glossary and extensive bibliography, are expressed in delightfully accessible prose. Some explanatory graphics depict various elements and mechanisms in furthering the reader's understanding. The underlying concept is "universality" and it's easy to see how his ideas apply to all animal life.

This is a valuable book, easily absorbed by students, professionals in many fields, including, in the final chapter, lawyers. The general public should be the primary market for this book since Marcus makes clear what has been learned may be applied in various ways, from "gene therapy" to "designer children". He doesn't avoid the hard issues in showing how recent science has closed off many myths while opening as many new options. Further research is needed, he argues, to avoid foolish mistakes. Those failing to read this book may make or allow those errors. [stephen a. haines - Ottawa, Canada]

This book's subtitle is misleading, although its main title isn't. This book is not about the how the genes actually allow complex thought, only that it's possible to reconcile a brain developed by genes alongwith a complex functioning mind. The author also addresses the apparent dichotomous ways in which the mind could learn and develop i.e. the nature/nurture dichotomy. He tackles it similarly to how Matt Ridley does, in Nature via Nurture.

The narrative of the book starts with a general explanation of what genes do and how they go about doing it; examines the concept of learning and reconciles prewiring of the brain with subsequent flexibility; how genes guide brain structural development and the flexibility they possess in doing so, in particular, how limited number of genes help develop an enormously populated and complex brain.

Now, if you have already read a few popular books on neuroscience or genes, this book has little new themes to offer. It's the same paradigm that most recent similar books reveal. This book is primarily useful to those who are reading their first or second work concerned with the biological treatment of the brain. In fact, if you are almost completely new to reading popular neuroscience, I suggest starting with Steven Johnson's Mind Wide Open.

All in all, this is a well-written read.

This is an extraordinary book. It brings the reader up to speed on the fascinating and important research that is uncovering how genes and the environment conspire to build brains of extraordinary complexity. The writing is crystal clear, the style is engaging, and Marcus makes the cutting edge science he's discussing accessible to any intelligent reader. This is science writing at its best. If you enjoy reading other great science writers like Pinker and Dawkins, you'll find this a great read!

I didn't plan on reading this book but it jumped into my hands, and I couldn't put it down. I already knew a lot about the topic, being a fan of Richard Dawkins and Stephen Pinker. But it was filled with great descriptions of fascinating lab work, which really pulled me in.

Now if you're not a fan of Dawkins or Pinker, it's probably for religious or political reasons; and I'd say to you: don't worry about this book. The subject matter was familiar to me because of those authors, but Marcus has none of their ideological verve. There's not even any philosophy. He didn't beat the nature/nurture horse: with this close of a look, it's just unnecessary. This is just about genes and brains; that's all.

So, if you're looking at this book, here are some others that I like that I think you might want to consider:

Richard Flanagan, The Problem of the Soul
Stephen Pinker, How the Mind Works
Matt Ridley, The Red Queen
Matt Ridley, Genome

This book is a very brief introduction into both genetics and neuroscience. The intention of this book is to make clear that nature (genes) is the basic foundation for the construction of the brain and its structure, which enables all complex mental functions. The author explains genes as "if...then" processes that can result in some specific trait, depending on the environment.

The author stresses that flexibility (the ability to receive information from the environment and act upon it, even reconfiguring innate structures of our brain circuitry) is a built-in characteristic of how nature chose to express genes. However, the explanations are not too deep and the studies performed in different areas are only mentioned as brief summaries. Several times the author mentions that we do not know enough about a specific function, which I completely understand. Unfortunately the things that we already do know are also too briefly explained. If this is your first book on genetics or neurosciences, it will give you a broad overview of the main ideas behind both, but if you have already read something about the topics, you will find not too many new insights.

If you would like a deeper explanation of the interaction between nature and nurture and how both express themselves in mental traits read Nature Via Nurture : Genes, Experience, and What Makes Us Human. If you would really like to understand the "if...then" processes from a molecular and genetical perspective I strongly recommend Life Itself: Exploring the Realm of the Living Cell and In Search of Memory: The Emergence of a New Science of Mind, which explains brilliantly how genetics is involved in neuroscience.

From the title & cover of the book I was expecting probably more topics on evolution and more specifics on how genes drive the formation of the brain in embryos.

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.