Is your brain really necessary?
1981; National Institutes of Health; Volume: 152; Issue: 18 Linguagem: Inglês
Autores Tópico(s)
Ethics and Legal Issues in Pediatric Healthcare
ResumoProfessor John Lorber has a facility for making doctors sit up and think about hallowed concepts, writes Adrian Bower, a neuroanatomist at Sheffield University, England, where Lorber holds a research chair in pediatrics. human brain is the current object of his challenging speculation, continues Bower, referring to his colleague's recent propositions concerning hydrocephalus, or water on the For instance, Lorber was not jesting totally when he addressed a conference of pediatricians with a paper entitled Is your brain really necessary? Lorber believes that his observations on a series of hydrocephalics have severely reduced brain tissue throws into question many traditional notions about the brain, both in clinical and scientific terms. There's a young student at this university, says Lorber, who has an IQ of 126, has gained a first-class honors degree in mathematics, and is socially completely normal. And yet the boy has virtually no brain. The student's physician at the university noticed that the youth had a slightly larger than normal head, and so referred him to Lorber, simply out of interest. When did a brain scan on him, Lorber recalls, we saw that instead of the normal 4.5-centimeter thickness of brain tissue between the ventricles and the cortical surface, there was just a thin layer of mantle measuring a millimeter or so. His cranium is filled mainly with cerebrospinal fluid. This is dramatic by any standards, and Lorber clearly enjoys retailing the story. But, startling as it may seem, this case is nothing new to the medical world. Scores of similar accounts litter the medical literature, and they go back a long way, observes Patrick Wall, professor of anatomy at University College, London, the important thing about Lorber is that he's done a long series of systematic scanning, rather than just dealing with anecdotes. He has gathered a remarkable set of data and he challenges, 'How do explain it?' How can someone with a grossly reduced cerebral mantle not only move among his fellows with no apparent social deficit, but also reach high academic achievement? How is it that in some hydrocephalics whose brains are severely distorted asymmetrically, the expected one-sided paralysis is typically absent? And how is one to interpret the apparent restoration to normality of a hydrocephalic brain following a shunt operation? These are the challenges that Lorber is proffering his neurology colleagues. Lorber came to make his observations on hydrocephalus through his involvement with assessment and treatment of spina bifida, a congenital condition in which the spinal column fails to fuse completely, leaving nerve tissue perilously exposed. The great majority of patients with spina bifida also suffer from hydrocephalus. Although the origins of hydrocephalus are to some degree shrouded in mystery, it is clearly associated with a disturbance of the circulation of cerebrospinal fluid through a system of channels and reservoirs, or ventricles, in the Back pressure apparently develops, and this may balloon the ventricles to many times their normal size, so pressing the overlying brain tissue against the cranium. In young children, whose skulls are still malleable, one obvious consequence can be a grossly enlarged head. Additionally, this physical assault from within leads to a real loss of brain matter. It is therefore not surprising that many hydrocephalics suffer intellectual and physical disabilities. What is surprising, however, is
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