WE KILL THEM BECAUSE THEY'RE POWERLESS:

Silent Minds: What scanning techniques are revealing about vegetative patients. (Jerome Groopman, October 15, 2007, The New Yorker)

Ten years ago, Adrian Owen, a young British neuroscientist, was working at a brain-imaging center at Addenbrooke’s Hospital, at the University of Cambridge. He had recently returned from the Montreal Neurological Institute, where he used advanced scanning technology to map areas of the brain, including those involved in recognizing human faces, and he was eager to continue his research. The imaging center was next to the hospital’s neurological intensive-care unit, and Owen heard about a patient there named Kate Bainbridge, a twenty-six-year-old schoolteacher who had become comatose after a flulike illness, and was eventually diagnosed as being in what neurologists call a vegetative state. Owen decided to scan Bainbridge’s brain. “We were looking for interesting patients to study,” he told me. “She was the first vegetative patient I came across.”

For four months, Bainbridge had not spoken or responded to her family or her doctors, although her eyes were often open and roving. (A person in a coma appears to be asleep and is unaware of even painful stimulation; a person in a vegetative state has periods of wakefulness but shows no awareness of her environment and does not make purposeful movements.) Owen placed Bainbridge in a PET scanner, a machine that records changes in metabolism and blood flow in the brain, and, on a screen in front of her, projected photographs of faces belonging to members of her family, as well as digitally distorted images, in which the faces were unrecognizable. Whenever pictures of Bainbridge’s family flashed on the screen, an area of her brain called the fusiform gyrus, which neuroscientists had identified as playing a central role in face recognition, lit up on the scan. “We were stunned,” Owen told me. “The fusiform-gyrus activation in her brain was not simply similar to normal; it was exactly the same as normal volunteers’.” [...]

For decades, doctors assumed that patients who have been diagnosed as vegetative lack any capacity for conscious thought. Most are previously healthy people who suffered a traumatic brain injury, or oxygen deprivation after a heart attack or stroke, and have been regarded more or less as zombies: patients whose bodies continue to function—sometimes for decades—but whose minds are incapable of willed activity. (The term “vegetative” was proposed in 1972, by Bryan Jennett, a neurosurgeon, and Fred Plum, a neurologist, who chose it based on a definition in the O.E.D: “an organic body capable of growth and development but devoid of sensation and thought.”) In the occasional newspaper stories about someone who suddenly recovered consciousness after spending years in a vegetative state, the event was invariably described as a medically inexplicable “miracle.” The Mohonk Report, a paper prepared by a group of experts in brain injury and presented to Congress last year, cited estimates suggesting that there are approximately thirty-five thousand Americans in a vegetative state and another two hundred and eighty thousand in a minimally conscious state—a less severe condition, in which patients show erratic evidence of deliberate behavior, such as responding to a simple command or focussing on a person or an object for a sustained period. Because insurers typically won’t pay for rehabilitation, on the assumption that such patients are unlikely to improve, most are given little in the way of therapy. “These people with brain trauma are out of our view,” Joseph Fins, an internist and medical ethicist at Weill Cornell Medical College, in Manhattan, and a member of the Mohonk group, told me. “We ignore them, and we sequester them in places where we can’t see them, usually in nursing homes.”

According to several American and British studies completed in the late nineties, patients suffering from what is known as “disorders of consciousness” are misdiagnosed between fifteen and forty-three per cent of the time. Physicians, who have traditionally relied on bedside evaluations to make diagnoses, sometimes misinterpret patients’ behavior, mistaking smiling, grunting, grimacing, crying, or moaning as evidence of consciousness. A neuroscientist showed me a video on the Internet of Terri Schiavo, the Florida woman who spent fifteen years in what most doctors agree was a vegetative state—tests revealed almost no activity in her cortex—and whose death, in 2005, provoked fierce debate over the rights of severely brain-damaged patients. (Schiavo died after the Supreme Court rejected her parents’ appeal of a judge’s decision approving her husband’s request that her feeding tube be removed. An autopsy showed extensive brain damage.) In the video, a man’s voice can be heard praising Schiavo for opening her eyes in response to his instructions, and the neuroscientist told me that he was impressed until he muted the sound. “With the sound off, it is clear that her movements are random,” the neuroscientist said. “But, with the voice-over, it is easy to make a misdiagnosis.” (The prognosis for patients such as Schiavo, who suffered brain damage owing to oxygen deprivation following cardiac arrest, is much worse than for those who suffer brain damage as the result of a head injury.)

Doctors can also miss signs of consciousness in vegetative patients, according to the British and American studies. Ten months after Owen and his colleagues completed the tennis experiment with the vegetative woman, she was brought back to the imaging center and placed in an MRI machine. “We were absolutely dismayed, because we scanned her and there was nothing,” Owen recalled. The team tested the woman again the next day. This time, in response to a command to play tennis, her brain showed normal activity in the regions that mediate arm movements. Owen now repeats scans for each patient, conducting them twice a day for three days. Patients with brain injuries have “seriously impaired attention capabilities and their levels of general arousal are likely to be shot,” he said. Recent research by Owen and other neuroscientists may eventually help make diagnoses more accurate, but it is not yet clear how the new brain-scan data will affect the medical understanding of consciousness. As Owen put it, “The thought of coma, vegetative state, and other disorders of consciousness troubles us all, because it awakens the old terror of being buried alive. Can any of these patients think, feel, or understand those around them? And, if so, what does this tell us about the nature of consciousness itself?”