Phantoms in the Brain

August 31, 1998
In these unsettling tales from a neuroscientist every bit as quirky as the more famous Oliver Sacks, Ramachandran sets out his beliefs that no matter how bizarre the case, empirical, strikingly simple testing can illuminate the ways brain circuitry establishes "self." In a chatty, nearly avuncular style, he (along with his coauthor, a New York Times science writer) snatches territory from philosophers on how we think we know what we know. In one experiment, stroking an amputee's cheek produces sensations in his "phantom limb" because the part of the brain's map that once related to the lost limb has "invaded" the adjacent brain area that relates to the cheek. Unafraid to speculate, Ramachandran then moves a step closer toward indicating that the brain is not only a busy lump of genetically deemed-and-dying hard-wiring but an organ that can continuously "re-map" in response to new sensory information from the outside. Equally fascinating are Ramachandran's "mirror tricks" on amputees and paralyzed patients that begin to reveal how much the brain relies on context and comparison as well as on "inside" neural connectivity to form self. Perhaps most disquieting are beginnings of proof that much brain activity, including what we like to think of as uniquely human behavior, happens unbidden. There may be no escape from the un-Western conclusion that self is only a limited illusion. "De-throning man," as the author points out, is at the heart of most revolutionary scientific thought. Regrettably, his book sags in the middle as it drifts from these deft experiments into generalized musings on idiot-savants and phantom pregnancies, detracting from what is otherwise entertaining, tip-of-the-neurological-iceberg sleuthing. Photos and line drawings throughout. Author tour.