A science-writer reviews the theories and research that have produced the current view of the brain as a dynamic structure with only superficial resemblances to a digital computer.
McCrone (The Myth of Irrationality: The Science of the Mind from Plato to Star Trek, 1994, etc.) first identifies what have been the two principal camps in the consciousness debate: first, those who view the brain as a vast and wondrous computer whose structures and strategies can be pinpointed; second, those who have a more dynamic view of the brain and employ new insights from chaos and complexity theory to understand its operations. In language often fresh and lively, McCrone meticulously moves around the brain, describing advances made possible by PET technology, by MRI and MEG (magnetoencephalography) scanning; summarizing the discoveries of researchers all over the world; correcting common misconceptions (e.g., that right- and left-brain functions are discrete)—all the while creating a comprehensive view of consciousness that reaffirms the brain’s preeminence as nature’s most remarkable achievement. Among the most interesting of his revelations is that the brain is in a constant state of anticipation: even when nothing is really happening, neurons are firing, keeping circuits ready, checking to see what’s new. The latest research demonstrates, too, that the brain’s feedback structure has created its vast capacities: “The history of the brain has its impact on the processing of the moment,” he writes, “but then the processing of the moment has its impact on the history of the brain.” Near the end is a fascinating chapter arguing that the development of tools and language were necessary for the emergence of consciousness. Recognizing that much of the earliest fundamental research on brain function involved the damaging of animals (holes burned in cats’ eyeballs, entire portions of monkeys’ brains suctioned away), McCrone is insistent that most of the newest research uses scanners and dyes that hurt no one.
A magical mystery tour made comprehensible and exhilarating by McCrone’s erudition and impressive expository gifts. (8 pages color photographs)
