Thursday, October 23, 2008

The Brain, from Atom to Soul

By: Lewis P. Rowland, M.D.

Lewis Rowland, a professor of neurology at Columbia University, writes that neurologist Adam Zeman's book about the brain from atoms to soul presents a succinct yet comprehensive literary tale.

We are blessed these days with an abundance of physician-writers who are interested in neurology. At the top of the list, of course, is Oliver Sacks. Now he and the others are joined by one more neurologist, Adam Zeman, a professor of cognitive and behavioral neurology at the new Peninsula Medical School in Plymouth, England. The school graduated its first class in 2007. 

Zeman writes smoothly and with a flair for the well-turned phrase. Each chapter is devoted to a different topic and comprises three elements: a particular aspect of neuroscience, a related explanation of a particular neurological disease, and a case report that humanizes that disorder. The author knows the patients and their symptoms well because they come from his own practice. In discussing the relevant science, he describes the history of our concepts about the disease because, he writes, “the history of a science is the science.” 

Zeman employs another unique idea as well: The chapters progress sequentially from the most basic to increasingly more complex units of life. Chapter 1, “Atom,” describes the importance of oxygen for human life and exemplifies the author’s fearlessness; he admits a medical error in the opening chapter. The patient, a 38-year-old woman, was thought to have chronic fatigue syndrome until her lips turned blue and she lapsed into a coma. Muscle biopsy disclosed a rare congenital disorder called multicore myopathy. With assisted ventilation through the night, she emerged from the coma, nocturnal sleep was restored, and her excessive daytime fatigue was ameliorated. Zeman concludes: “Instead of nervously concealing them, we should examine, even celebrate, our failures and mistakes. Rather than being negligent or shameful, as a rule, they are a fact of life, a plain reflection of human imperfection.” 

Chapter 2, “Gene,” deals with diseases characterized by involuntary movements, some of which are inherited. That leads to analysis of DNA by way of acanthocytes, from a Greek word meaning “thorn.” These prickly-looking red blood cells appear in only a few diseases. In this case, recognition of the misshapen cells led to a diagnosis of McLeod syndrome rather than Huntington disease, the equally malignant cause of chorea. “Chorea” encompasses the random jerking of limbs and derives from the Greek word for dancing (whence, also, comes “chorus”). In the context of this patient, “Charley,” Zeman celebrates the achievements of molecular genetics: “Most of the genes that cause acanthocytosis have been lassoed in the past ten years. Around 60 genes causing inherited forms of incoordination and unsteadiness and a dozen causing inherited Parkinson’s disease have been described at a rapidly accelerating pace.” But then comes the jolt: “Delivering really effective treatment for these disorders . . . is, so far, an unrealized ambition. For Charley, the discovery of the cause of his predicament provided cold comfort. I was unable to rescue him from his fate. His last few years were spent in psychiatric custody.” Zeman’s comment is a constant source of general concern: Discovering genes has been a major advance for medicine but, lamentably, treatment for these diseases is largely unavailable. Gene therapy has commenced, but it has a long way to go.

Chapter 3, “Protein,” starts with a description of scrapie, a disease of sheep. Back in 1936, two French veterinarians proved that if brain tissue from an infected animal was injected into the brain of a normal animal, the disease appeared a year or two later. The first Nobel Prize for research on this kind of rare disease was awarded to Carlton Gajdusek, who confirmed and elaborated the transmissibility of Creutzfeldt-Jakob disease (CJD); when brain samples from a victim of the killer disease were injected into a monkey, the recipient later developed the telltale symptoms. So came the era of “slow virus infection,” “transmissible spongiform encephalopathy,” and, ultimately, “prion disease.” The case example here is one of Creutzfeldt-Jakob disease, with appropriate attention also to the other diseases in the category as well as the causal self-replicating proteins called prions. That word was invented by Nobelist Stanley Prusiner, who won the second Nobel for work on a disease as rare as CJD; he described the infectious agent as one that replicates but has no DNA, a wondrous exception to conventional laws of genetics. Prusiner called the agent “proteinaceous infectious material,” from which came the name “prion” (which he pronounced “pree-on”).

Continuing up the ladder of cellular complexity, we reach “organelle.” The subtitle of this chapter is “Metamorphoses,” which describes the bacterial origin of human mitochondria millions of years ago and the current diseases of these intracellular structures. Salvatore DiMauro, Michio Hirano, and Eric Schon have written a monograph in this field, which they call “mitochondrial medicine.” The term encompasses several neurological syndromes, including Kearns-Sayre syndrome, mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) and others. Non-neurological manifestations include diabetes mellitus and fatty deposits or “lipomas” under the skin. Perhaps more significant, mitochondrial malfunction is considered important in the many age-related degenerative diseases of the brain and nervous system. Here, Zeman explains the basics of the maternal inheritance of mitochondrial DNA and how it has become a boon to anthropology.

Chapter 5, “Neuron,” describes the debate about synapses between two giants in the history of neuroscience, Ramón y Cajal and Camillo Golgi. They shared the first Nobel Prize, in 1906, but their enmity was evident in the lectures they presented at the award ceremony. Golgi developed a stain that is still used to study the ramifications of neurons in the brain, but he concluded, in Zeman’s words, that the cellular projections “unite to form a fused network of fibres.” The chapter explicates the role of ions in neural transmission, and the case history describes a young man with epilepsy.

Chapters 6 through 8 take us from “Synapse” to “Neural Networks” and then “Lobe,” and from narcolepsy to déjà vu and on to the emergence of creativity as dementia becomes more and more severe.

Chapter 9, “Psyche,” focuses on somatoform syndromes, which are psychological disorders marked by physical symptoms for which no physiological explanation is found. Here, Zeman is brave enough to use the word “hysteria,” a term that has been set aside by many writers and psychiatrists as sexist. The word “hysterical” comes from a word in both Latin and Greek that means “womb,” or “uterus.” The word was originally used to describe symptoms without evident cause, considered peculiar to women and attributed to dysfunction of the uterus, but we now recognize the condition in men as well as women.

The last chapter, “Soul,” would be difficult for anyone—neurologist, philosopher or theologian—to tackle. Zeman writes: “The words we use when we think about the mind are quite different. ‘Mind’, ‘soul’, [and] ‘consciousness’ are not scientific terms, and lack technical definition. Our understanding of them is powerfully influenced by religious and philosophical traditions. So there is an inevitable risk of a disconnection here between scientific enquiry and everyday thought.” Neurosurgeon Wilder Penfield demonstrated by brain stimulation in the course of epilepsy surgery that thoughts arise in the brain. Yet even he became a dualist, describing a soul separate from the flesh. Zeman is correct in ascribing the concept of a soul to the worldview of most people, but this concept is rejected by atheist philosophers, including the popular science writer Richard Dawkins and the literary critic Christopher Hitchens.

Neuroscientists, neurologists, psychiatrists and general readers should all enjoy and benefit from reading this comprehensive yet succinct book, as Zeman shows how interest in a clinical condition can lead to science, human experience—and fine literature.

About Cerebrum

Bill Glovin, editor
Carolyn Asbury, Ph.D., consultant

Scientific Advisory Board
Joseph T. Coyle, M.D., Harvard Medical School
Pierre J. Magistretti, M.D., Ph.D., University of Lausanne Medical School and Hospital
Helen Mayberg, M.D., Icahn School of Medicine at Mount Sinai 
Bruce S. McEwen, Ph.D., The Rockefeller University
Donald Price, M.D., The Johns Hopkins University School of Medicine
Charles Zorumski, M.D., Washington University School of Medicine

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