This is the Safari online edition of the printed book.

Discover the Other 90% of Your Brain

• Learn about brain science breakthroughs that might hold the key to intelligence, creativity, and imagination.

• Discover amazing cells that keep your brain growing, adapting, and healing.

• Preview possible breakthroughs for brain cancer, brain trauma, Alzheimer’s, Parkinson’s, and even schizophrenia.

If you know anything about brains, you’ve heard of neurons. Those are the cells that have long been seen as central to virtually everything your brain thinks, feels, and does. But neurons represent only 10% of your brain cells.

What does the other 90% do?

Until recently, scientists didn’t have a clue. Now, they’re discovering the real function of those long-neglected glial cells—and the story is nothing short of amazing.

In The Root of Thought, brain scientist Andrew Koob reveals that story. You’ll learn what glial cells are, how they function, and how they might help explain everything from intelligence and creativity to imagination and dreams. Then, Koob reveals the tantalizing clues about glial cells that could eventually lead to cures for brain injury, psychiatric disorders, Alzheimer’s, Parkinson’s, Lou Gehrig’s disease, and even brain cancer.

Amazon.com® Reader Reviews (Ranked by Helpfulness)

Average Amazon.com® Rating:  Based on 5 Ratings

The science is interesting, the book is not - 2009-09-27
Reviewer Rating:
The Root of Thought is Andrew Koob's book about the emerging research suggesting that the glial cells in our brain ("the other 90% of our brain) may serve more of a vital role in thought processing and other brain functions than was ever previously understood. Koob is a brain scientist, and it is clear from the very beginning of his work that it was written by a researcher and not someone more classically trained in literature. The book seems to have been written without an intended audience in mind because it is this reviewer's opinion that it is not nearly accessible enough to be enjoyed by the casual reader yet oversimplified for the neuroscience aficionado. As a reader, it was difficult to become engaged with the text because it seemed to assume a fair bit of neuroscience fluency that the average individual does not possess. As a college biomedical engineering major I found myself frustrated by a lack of detail at times and at other times inundated with references to brain physiology that were unfamiliar to me. I did not find the book to be an enjoyable read; however, the science upon which the book is written is fascinating.

The first quarter of the book is devoted to the history of brain research from the beginnings of electrophysiology up until the recent decades when the importance of glia has begun to emerge. It summarizes that glial cells were thought to merely be insulators for neurons without serving any other functional purpose, and that the only important cells in the brain were neurons (Neuron Doctrine). Consequently, the research that followed over the nearly 100 years that followed focused almost exclusively on neurons. These three history chapters could (and probably should) be condensed into one short chapter that gives the reader a basic understanding of the Neuron Doctrine and explains why science is only just beginning to understand the importance of glial cells. The history section as it is currently written is overly drawn out, references entirely too many studies that most readers are surely unfamiliar with, and includes several unnecessary and inappropriate personal references from the author revealing his frustrations with the pioneering brain scientists responsible for the establishment of the Neuron Doctrine.

The subsequent chapters discuss the functional mechanism of glia (more specifically astrocytes), their possible role in intelligence and thought generation, their connection to dreams, and their potential to be used to treat brain diseases. These sections are better than the first, but require too much effort by the reader to identify conclusions and determine what is important.

Astrocytes communicate to themselves as well as neurons using calcium waves, and it is hypothesized that these calcium waves are the roots of our thoughts. The calcium waves may be the mechanism by which we store information in our cortex and how we can think about what we have experienced. Astrocytes help to form neuronal synapses which help to increase intelligence by increasing the speed we can process information, but astrocytes are also capable of spontaneous firing without neurons, which may be the source of inspiration and imagination. It has been shown that having a higher glia - neuron ratio correlates with higher intelligence, and since humans have the highest ratio of any animal, this may explain our intellectual dominance over the animal kingdom. Koob also mentions that "Einstein had a [significantly] higher astrocyte-to-neuron ratio in the area of the left parietal cortex" as compared to "normal" brains, which may explain his increased ability in mathematics and spatial thinking (104).

Astrocytes are thought to be more active at night, doing most of their regeneration during this time. Koob suggests "the rapid eye movements seen in REM sleep could be glia experimenting with the neuronal firing to make sure their connections are solid" (112). The astrocytes respond to a day's worth of sensory input by growing new astrocytes in the regions that were most commonly used. It is thought that this glial activation during the night may be the source of dreaming, and since it is easier to instigate calcium waves in cells that have been previously activated, it seems that our dreams are the direct result of our recent experiences.

Another key function of astrocytes is the maintenance of neurons, mainly in the form of removing cellular waste such as glutamate. There is evidence to suggest that several of the common brain degenerative diseases may be the indirect result of gliadegeneration. It is hypothesized that with fewer astrocytes available to remove the cellular waste, the neurons themselves begin to degenerate. Additionally, it is thought that astrocytes serve to prevent secondary neurodegeneration following a head injury. Much of the research regarding brain injury focusses on the possibility of injecting astrocytes into the damaged brain area to see it will help to maintain the health of the neurons. Koob states, "In the event of a gunshot wound to the head, astrocyte therapy may be the only avenue to regrow areas of the brain" (137).

As was mentioned in a previous review, most of what Koob discusses in this book is purely speculation at this point as the research in this field is only in its infancy. I question whether Koob is justified in making several of the claims that he does regarding the importance of glia without more concrete studies to support such statements. It appears he may be falling into a similar trap as the Neuron Doctrine by focusing so exclusively on glia. The reader is cautioned not to take Koob's writing as fact, but merely as speculation as to the potential functions of glia. Overall, the science that Koob discusses in his book is really quite fascinating, which makes it a shame that it is written so poorly. The average reader with an interest in the subject should pursue an abbreviated outline of the text that summarizes the interesting points rather than the text itself as it is not accessible to those without at least a minor familiarity with the subject matter.

best book I've read since 1958! - 2009-09-07
Reviewer Rating:
51 years ago I started my PhD program in psychology At UCLA. The next year I started taking the courses I needed at the medical school. After my first course in neurology I started asking questions about the professor's claims that glial cells were nothing but "packing" to protect the neurons. I just couldn't buy it. Every time I tried to start a conversation I was pretty much told to hush and go away. I did. Fortunately, I met a med student in the lounge with whom I made a long-term fond acquaintanceship. He ultimately became the director of the brain research institute and for the next 45 years I checked in with him to learn whether better information had become available on glia yet. If it had, he didn't know or remember that THAT subject was the main reason I had stayed in touch with him. He was, apparently, no more interested in alternatives to the standard crap than anyone else, so Koop's book was the first hint I had that I was not absolutely alone in suspecting that glial cells were WAY more important than so far imagined. When I saw this book reviewed in a magazine, I ordered it and started reading the minute it arrived. [I had been forced to move from researcher to clinician in grad school and then promoted quickly to department head in a hospital so I had not stayed in touch with this research issue]. On the first page I broke into joyous hysterics. I'd been right! Koob, a couple of generations later, had a PILE of findings I hadn't had and he had hypothesized pretty much what I had imagined as a possibility. Now, at age 74, retired from salaried work and enjoying a life of writing and illustrating books about whatever is intriguing me at the moment, I had only one embarrassing problem: I couldn't stop LAUGHING over finally getting a possible ANSWER to my 50 year old question: what the hell do they think 90% of the brain cells are FOR????????? cv

This author uses his glia! - 2009-10-14
Reviewer Rating:
I love this book. I love glia, too. I believe that they are to the brain what fascia is to the body. Both have been looked down upon as mere support structures, whereas they may be the true control towers. The thread running throughout this book concerns the blinders worn by the medical research establishment, and the loss of ability to perform a paradigm switch and think outside the box once a box is built. One powerful researcher decided the neuron was king and the glia were spearholders, and time after time research showing otherwise was dismissed. Money was poured into neuron research, while glial cells remained the poor relation. The work done by Dr. Linda Watkins and her team has shown that central sensitization of the nervous system, leading to conditions such as fibromyalgia, comes about through sensitization of spinal cord glia. Glial cells, especially astrocytes, are coming into the spotlight, and perhaps we are beginning on the journey to finding out what the other 90% of the brain is doing. This story of glia is told with wit and humor. The book was enormously entertaining.

The Hidden Power in the Brain? - 2009-10-08
Reviewer Rating:
In recent years there has been an increasing understanding that the functions of the brain cannot be reduced to simple on/off firing of neurons. In addition to new insights into the ways in which networks of neurons cooperate, modulate and recruit each other, there has been growing interest in the glia cells of the brain, that outnumber neurons by around ten to one. Long thought of as no more than supporting and scavenging cells, several years ago we learned that they are electrically active and have far more complex interactions with each other and with neurons than we had ever thought possible. In a recent article in Discover magazine, Carl Zimmer called these cells the "Dark matter" in the brain. Glia cells are able to store information, appear to be involved in many pathological processes in the brain, and the simple observation that most brain tumors are comprised of glial cells ultimately lead to the understanding and demonstration that glia cells are the adult stem cells in the brain.

In the last five years a number of scholarly books, (e.g. The Tripartite Synapse: Glia in Synaptic Transmission, Glial Neurobiology) have detailed some of these new findings, and in this new book by Andrew Koob we have a highly readable account of some of this work, together with some interesting speculations by someone who unashamedly proselytizes about the role of these largely ignored cells. The book begins with an historical overview and a description about what glia do and what is currently known about their function. Andrew focuses on their role in neurogenesis - the creation of new neurons - neuroplasticity - the ability of the brain to adapt to environmental change - and in brain repair. He then goes on to suggest that a better understanding of these cells is important for out understanding of how to help brain injury, Alzheimer's disease schizophrenia and an array of other neurological problems, including tumors on the brain. He also implies that because of their role in neurogenesis and neuroplasticity, glia cells are involved in memory and dreaming.

Time will tell if all of his speculations turn out to be correct, but at the very least he has assembled an impressive body of evidence for a general readership and has thrown down a gauntlet to researchers.

The book is well written and apart from the central argument, contains plenty of factoids to keep your attention.

Very highly recommended.

Richard G. Petty, MD, author of Healing, Meaning and Purpose: The Magical Power of the Emerging Laws of Life

Fascinating - 2009-09-15
Reviewer Rating:
This is a rather speculative work. There are a good many "maybe"s, "might"s, and "perhaps"es. Perhaps not enough. (But see below.) There is also the occasional rhetorical excess: "we are our astrocytes." Some stylistic infelicities, the author's self-characterization as a brave and lonely voice and a vendetta against Ramon y Cajal detract only slightly from the overall interest. Attempts at the common touch through pop culture references and a fondness for similes don't always serve the writer well.
BUT data supporting Koob's main point on the significance of neuroglia, specifically astrocytes, for mental functioning is coming in. For example, work cited by [...] in two recent articles:
1."Astrocytes help separate man from mouse"
Researchers at the University of Rochester Medical Center: "Our
study suggests that astrocytes are part of the higher cognitive functioning that defines who we are as humans." (3/23/09)
2."Star-shaped cells in the brain aid with learning" (9/07/09)

Future books on the brain which ignore this data may risk rapid obsolesce. But I would dearly love to read a review by someone with serious neuroscience cred. 4 1/2 stars
10/03/09 This just in: the oft cited figure of 10 times as many glia as neurons, repeated by Koob, may be wildly off. Some recent
data suggest 1:1--Neurocritic blog 9/27/09.

Browse Similar Topics

Top Level Categories:
Business

Sub-Categories:
Business > Personal Development