dates back to Descartes that drastic separation between emotion and intellect, which for centuries has been a guiding policy research, and a speculative principle does not infringe. But the reality is proving to be different. In particular, the fascinating currently ongoing investigations into the brain moving in the opposite direction. Damasio was perhaps the first to be placed under careful consideration the dire consequences of the separation of Descartes, and it is now possible to give that error not only on the basis of speculative arguments, but also from the analysis Clinical cases - that Damasio presents a lively narrative comparable to that of Sacks - the evaluation of experimental neurological facts. All the lines seem to converge towards the same end: the essence of the cognitive value of emotion. Forcing the current linguistic expression, Damasio use "feeling" to denote something new conceptually, and introduces an important distinction, and so far not detected between the basic feel and feeling of emotions that distinction here is based on observations of anatomical architecture functional central nervous system and not only on grounds of psychological functionalism (such as in Johnson-Laird). It makes it a great step forward towards the clarification neurobiology of emotional capabilities and its tight twists with rational action. Right here are concentrated on the news, that make this book one of the most exciting reading in a field - the relationship between brain and consciousness - which is still a lot to discover. Phineas Gage was a skilled and experienced American labor leader, that in an unlucky day for him in 1848, had his skull pierced by a pile of iron three feet long and ten centimeters, a diameter of about three centimeters. The pole, shot accidentally by the explosion of a blasting charge, penetrated into the Gage's left cheek and left the top of his skull had crossed the front of the brain. Gage lost consciousness for a few minutes. He was treated by a very capable doctor - Dr. John Harlow - who avoided the worst consequences of the inevitable infection. Healed, and not only that his cognitive abilities (language, reasoning, etc..) Are essentially intact. Yet, had undergone a fundamental change, which would have made impossible a normal life. In the words of his doctor, he had become "bizarre, insolent, capable of coarse expletives (which previously had been completely alien) ... sometimes stubbornly stubborn, and yet capricious and fluctuating: always ready to develop many programs of future activities that out as soon as he had outlined. " He was unable to return to his old job, n, to take them more for a sufficient period, died in San Francisco in 1861, perhaps following a series of attacks of epilepsy. What exactly had happened to Phineas Gage, and what happens to others who, like him, suffer an injury to the selective prefrontal cortices of the brain? Damasio's excellent book, well translated by Philip Macaluso, is - among many other things - an attempt to answer this question. The answer is detailed, and involves a lot of knowledge and speculation, not a few (not all mandatory, but always interesting): among other things, is interwoven with a theory of the relationship between mind and body, with a hypothesis about the cost- tution of the self and consciousness and a theory of emotions and feelings. Here I will confine myself to the main line of this plot. The problem is clear. Patients prefrontal Gage behave as "irrational": in particular, are being impaired their decision-making. For example, on one occasion a patient of Damasio, having to choose the date for the next (a Decision trivial and not particularly problematic), went on for almost half an hour to weigh the pros and cons of the alternatives in relation to other commitments under the conditions of time, to every possible element interferences, but then accept without hesitation the date proposed by the doctors. Still, these patients have no abnormalities cognitive processes: they talk and think normally. This suggests that the decision is not a purely cognitive task, that is not - how would a tradition that comes from Kant to modern theories of rational choice - a pure calculation of costs and benefits, which examines one after the other courses' Finally, possible action by choosing one characterized by the highest "expected utility". If you really had to decide in this way, we would like the brain studied by Damasio: he shall go no. We always under the conditions of the donkey of Buridan, who dies of hunger could not decide between two haystacks. Of course, if the two piles of the donkey were the same, but the point is that it is not always easy to determine - In cognitive terms closely - which of two piles is the biggest: "It is not easy to keep in mind the multiple levels of gains and losses that we must compare: simply disappear from the board memory representations of the intermediate steps that must be taken into Serbian. .. Of those intermediate steps seems lost, as attention and working memory have limited capacity. " Where a decision can be on time and resources normally available to a human being, there must be an automatic mechanism that simplifies dramatically, and the alteration of this mechanism must have caused the impairment faced by prefrontal patients. This mechanism, for Damasio, has to do with emotions, which play in the production of rational behavior, a role far more important than what they are usually attributed. Damasio believes that there are good reasons, both neurobiological and psychological, to dismiss the image established that emotions were evolutionarily more ancient prerogative of the nucleus of the brain (hypothalamus, limbo, etc..), While rationality is managed by the cerebral cortex recently. According to him, rationality is what we call the combined effect of recent antique pieces and parts. When deliberating, the results of alternative courses of action that we imagine is connected to the somatic marker, positive or negative. The marker is a signal that serves to encourage or discourage the choices to the outcome of which is associated, so that they are strongly preferred or excluded from consideration instead of acting. The clearest example of somatic marker (negative) is the queasy feeling in your gut we feel when we imagine a negative outcome of some possible choice. But it is essential that the body undergoes a change really, there is an alternative mechanism in which the body is bypassed: the prefrontal cortex and the amygdala tell the somatosensory cortex of organizers or-as if the body had been put into a certain state. The brain, in other words, the body receives an "excited" even if the body is not really changed. In both cases, the idea is that the alternatives are also short-listed according to their emotional content, where emotion is a set of changes in body state connected to particular mental images that have activated a specific brain system, and feel an emotion is the experience of those changes in juxtaposition to the mental images that initiated the cycle. I do not know what the anticartesiano Damasio is aware of the strong similarity between his way of looking at feelings and emotions and the theory of the passions of a large Cartesian heterodox, Spinoza: the feeling, Damasio, is the experience of what the body ago, "while racing thoughts regarding specific content "Spinoza, emotions and feelings in the unifying concept of love, said that an affection is a 'disease of the body ... and the whole idea of \u200b\u200bthis disease. "A very clever series of tests show that the prefrontal patients are less able to emotions of normal subjects, in effect, for example, that images do not exhibit somatic responses to emotionally, knowing that These emotionally charged images, and being perfectly able to explain what is specific emotions: they are able to say that a picture should horrify, but nothing in their body expresses such a horror. In them has broken the circuit imagination - somatic responses - mental change than in normal subjects is the basis of deliberative processes. On the other hand, there are according to Damasio neurobiological reasons to believe that the prefrontal areas are the ones responsible for managing most of the processes involved in the circuit. The image of a brain that sends signals to the body and in turn will "listen" continuously and carefully the answers ("the brain is bound with the hearing officer of the body") is generalized, in Damasio's book, an image of the relationship between mind and body and a theory of the self, which is central to the continued representation of the cerebral state of the body. The self is in fact part of autobiographical memory (as we know their names, where we live, what we like, what life we \u200b\u200blived, etc..) and in some cases not less than the constantly repeated representation of the state of our body, hence the painful loss of self of patients with anosognosia, which are doomed to a knowledge "objective," outside of their bodies before, because their mind no longer perceives its present state. And here also the anti-Cartesian polemic of Damasio (which gives the title to the book, and is largely unfair) against the Cartesian dualism - the separation of mind and body - and subject against the priority of mind over body, which would be expressed by famous "Cogito ergo sum". For Damasio, on the contrary, the mind and body comes from the fact whole body, not only from the brain. Review of Marconi, D., Index 1996, No. 2
Info for purchase
0 comments:
Post a Comment