Descartes' Error: Emotion, Reason, and the Human Brain Paperback – September 27, 2005

I’ve joked that there must be a law requiring any author writing a book on neuroscience for a popular audience to tell the story of Phineas Gage. This book is no exception. Its first couple chapters explore the case of Gage in detail. For those who don’t read much on this subject, Phineas Gage was a foreman for a construction company. By all accounts he was a reliable and solid individual, respected by his employees, trusted by his employer, and beloved by his family. Then one day a four foot tamping rod was blown through his skull – literally, in one side and out the other. One might think that having a chunk of brain skewered out by a steel rod on a gunpowder-fueled ride through the skull would leave one – at best -- a glassy-eyed, drooling, catatonic lump. Surely, a steel rod would wreak more havoc than the narrow needle used in lobotomies? However, what makes Gage’s story fascinating is that the injury resulted in no readily apparent disruption in cognitive function. Gage could still speak fluidly. He retained his memories. He could do math at the same level as before. However, this isn’t to say that the hole through his brain left him unchanged. The even temperament that made him an ideal employee and that endeared him to friends and family was gone. Gage became angry and unreliable.

So what is the relevance of the Gage story to Damasio’s book? Quite a lot, actually. Damasio’s book is about emotion, its influence on decision-making, and how bodily states create emotion. In parts two and three of this three part book, after introducing the reader to the role of the brain in emotion via the cases of those with selective brain damage, Damasio lays out an argument for what he calls the “Somatic Marker Hypothesis” which says that bodily states are what create the sensations that we associate with emotion. The title-referenced error made by Descartes will be apparent to those familiar with Cartesian dualism. Descartes believed there was a dualism between mind and body – i.e. that there was this physical stuff that got us about from place to place, but there were these intangible thoughts and feelings that were matter-independent that were the makings of mind and which were really you (i.e. you think, therefore you are.) Damasio believes that you cannot separate what it feels like to be you from the body and all its hormones, neurotransmitters, vital statistics, neuronal firing, etc.

The book consists of eleven chapters divided into three parts. In the first part, the author lays out not only the case of Gage, but other examples of individuals who had injury or illness in the brain that disrupted emotion and its influence on decision-making. We learn that an unemotional being isn’t like Spock, but instead is paralyzed by indecision. It turns out that it’s emotion that give us a kick, particularly when he have no sound basis on which to make a rational judgement. The second part draws the connection between body and our emotional self, culminating in a description of the Somatic Marker Hypothesis. The final part describes how the Somatic Marker Hypothesis could be tested and where this line of study seems to be going. The book is annotated and has a bibliography as one would expect of a scholarly work – even one written for a popular audience. The book has a few graphics – graphs, charts, and diagrams, but not very many and of a clear and simple nature.

I’d highly recommend this book for anyone interested in the working of the mind. It’s a thought-provoking look at what it means to be an emotional being and challenges our preconceptions about feelings.

After reading Descartes' Error: Emotion, Reason, and the Human Brain, I wanted to give an overview of the book, and insight on how to go about reading it. First off, I would suggest this book to anyone who thinks that they are a logical thinker and decision maker that does not let emotion interfere with their decisions. Damasio uses case studies prolifically to support his hypotheses that the mind and body cannot be separated and are in fact an integrated unit.

If you are interested in reading about topics dealing with the mind, and this is the first book that you are choosing to read it will more than likely be a challenging one. Damasio uses numerous of anatomical names for structures and disease names within his book. If you are not familiar with the brain you will be constantly going to Wikipedia or Google to figure out what exactly he is talking about. I would highly suggest starting off with a different book that simply goes over the brain in general before tackling this one. While Descartes' Error can be informative it is much more enlightening and enjoyable if you already know the jargon. That way you will not have to stop reading every other paragraph to go online and look up terms.

The book itself is divided up into three parts. The first part looks into older case studies where people suffered brain injuries and after "recovery" had a change in both their personality and decision making ability. The most notable one is of Phineas Gage who had an iron rod go through his head and damage his frontal cortex. From this injury he had the symptoms listed above for the rest of his life. The second part of the book looks into explanations for why injuries such as the ones listed in the first part effect both decision making and personality. The final part of the book delves into ways to test these explanations and Damasio ends the book by giving an explicit explanation as to what he believes Descartes' Error was in regards to the books topic of the mind and body. For those who do not know who Descartes you will probably know a very famous quote by him, "I think therefore I am". He was a famous philosopher and mathematician from France. It would be beneficial to read the Wikipedia page on him before starting this book as well.

As I have stated before this book can be very dense and labor intensive to read if you have never taken a neuroscience course or read any books on the brain before. Some sections will have to be read over a few times for the information to sink in and really make sense. Damasio includes asides throughout the book on various topics and ideas that he mentions in the main text. These blurbs while helpful are generally where you are going to feel the most confused. The topics that he discusses in these asides, like Phrenology, have whole books written on them, and Damasio only has a few paragraphs on the topic. He tries to get as much information in as possible, and you can feel like your in over your head because the it is just that dense.

All in all for books on the brain I would say that this is a must read. Damasio presents plausible hypotheses and does a good job supporting them. The thing that I like most is both at the beginning and end of the book he makes sure to mention that what he has stated are just hypotheses and that they are not facts. They are conjectures. The field of neurobiology does not have all the answers, so while his hypotheses seem to fit they are not the end all and be all.

I bought the Kindle version for a class. Great information by Antonio Damasio, who has become one of my favorite psychological sciences scholars to reference and learn from. Relatively easy to understand for the lay person, although some sections might be a bit advanced for a person lacking prior knowledge in brain science, psychology, etc. A great reference book as well. Would have given 5 stars, except that I've noticed that sometimes the Kindle versions don't display well (ie. illustrations) depending on the reader one is currently using. Being able to take notes with the Kindle version was a plus for class though; I certainly didn't have worry about any stickies falling out of the book!

Everyone should read this book. What Damasio has to tell us about the role of emotion in our reasoning process is fascinating and profoundly important, especially in our culture that wrongly teaches us that the two are separate and that engaging emotions in the reasoning process is a fault of logic. Beautifully written for the layperson without dumbing down the message.