Descartes' Error: Emotion, Reason and the Human Brain

"A "negative" title such as this carries unfortunate implications. The "error" must be identified, then explained and refuted. For newcomers to cognitive studies, Descartes "error" might seem an obscurity . Yet it has been the basic tenet of education and social thinking in the Western world for three centuries. "Cogito ergo sum" was translated into the belief that the mind and the remainder of the body were separate entities. Behaviour was controlled by the mind, while the body went about its own business. Damasio demolishes that long-standing mistake for good in this superbly written groundbreaking study.

The first indication of the relationship of the mind and body was the bizarre penetration of a railway worker's skull in 1848. The worker lived, but the damage to his brain left him with severe personality changes. The case opened the door to research leading to mapping areas of the brain that reflected various personality traits. Damasio recounts the incident, matching it with numerous clinical studies of his own. Additional work, some of it strongly innovative led Damasio and his colleagues to a reformulation of how the mind and body interact.

He reminds us that the brain is much more than a collection of electrically interacting cells. The body is sending information to the brain almost continuously, with the brain replying or initiating communication. These signals are both electrical and chemical. More importantly, Damasio reflects on the evolutionary origins of these conditions. For him, it is inevitable that the mind and body interact intimately. His proposed appellation for Emotions aren't separated from our reasoning processes, but are an integral part of them. The attempts by parents and educators to "train out" emotions in children are thus doomed to fail.

Damasio's thesis hinges on what he calls "somatic markers." The markers are areas of the brain which continuously interact with the body, particularly those areas we associate with emotions. If confronted with emotionally charged choices, the stomach "knots," the face may "flush" warmly, and perspiration may increase markedly. These body/brain functions begin developing early in the embryo. Indeed, they have a long evolutionary history, which firmly establishes their roots. In humans, the brain not only controls/reacts with the body in addressing stressful circumstances, but retains some level of memory of the events causing the reactions. Hence, even thinking about such circumstances can lead to bodily reactions associated with them. You need not be confronting an emotional situation to be able to express the feelings associated with it. This, of course, is most notably seen in actors or other performers. Damasio offers the excellent example of orchestra conductor Herbert von Karajan, whose pulse rate was higher while conducting than when confronted with an emergency situation in an airplane. To Damasio, "Descartes' error" was that he placed all these controls in a central location of the "mind" where, in fact, they are scattered over much of the brain.

The implications from this book will be far reaching. Besides impacting academic courses on behaviour, there will be changes in how we parent, how we deal with education, and even in the realm of law. Binding reason and emotion will revise uncountable long-standing ideas about how the mind deals with our surroundings. It is a work addressing fundamental questions about what make us human. Read it with care, aware that many preconceptions are likely to be challenged. The rewards for this effort will be great in years to come. [stephen a. haines - Ottawa, Canada]"
~ Written on 2005-06-06