This chapter is from the book
This chapter is from the book
This chapter is from the book
A rare mistake?
The implications of the discovery are haunting. How many patients currently labeled vegetative might show similar patterns of mental activity on an fMRI scan? There are an estimated 25,000 to 35,000 vegetative patients in the United States alone.5
Nicholas Schiff, a leading American researcher on impaired consciousness, says that while the study showed "knock-down, drag-out" proof of awareness in this patient, it is unclear "whether we'll see this in one out of 100 vegetative patients, or one out of 1,000, or ever again."6 Most neuroscientists are of the opinion that the vast majority of vegetative cases would not show the complex mental activity that the young English woman did. Many of these patients—Theresa Schiavo among them—have suffered extreme oxygen deprivation and have lost a massive number of neurons. Steven Laureys, director of the Coma Science Group at the Cyclotron Research Center at the University of Liége in Belgium, reports that his team has "not observed any similar signs of awareness in functional scans of more than 60 other vegetative patients studied at the University of Liége."7
Dr. Laureys coauthored the imaging studies with the young English patient, and he notes that even for experts in impaired consciousness, "the vegetative state is a very disturbing condition. It illustrates how the two main components of consciousness can become completely dissociated: wakefulness remains intact, but awareness—encompassing all thoughts and feelings—is abolished."8
The chance of recovery is greater for victims of a traumatic brain injury like the young English patient, whose injuries are severe but localized. An estimated one-half of all patients who are unconscious due to traumatic injuries—often the victims of car accidents—regain some awareness within a year, whereas only about 15 percent of those with brain damage due to oxygen starvation recover any awareness within the first three months (and very few do after that). A study of 700 vegetative patients in 1994 showed that no patients with injuries from oxygen deprivation recovered after two years.9
"One always hesitates to make a lot out of a single case, but what this study shows me is that there may be more going on in terms of patients' self-awareness than we can learn at the bedside," said Dr. James Bernat, professor of neurology at Dartmouth Medical School. "Even though we might assume some patients are not aware, I think we should always talk to them, always explain what's going on, always make them comfortable, because maybe they are there, inside, aware of everything."10
Kate Bainbridge from Cambridgeshire, England, agrees. She believes that she, too, has much to owe Dr. Owen's brain imaging research. She was 26 years old when she succumbed to a viral infection that caused severe brain inflammation, leaving her vegetative for six months according to standard bedside tests. Dr. Owen had begun using scanning technology—in Kate's case, positron emission tomography (PET)—to investigate patterns of brain activity in patients diagnosed as vegetative. A PET scan takes a biologically active chemical like glucose, tags it with a detectable radioisotope, and records its uptake by active brain cells.
Dr. Owen showed Ms. Bainbridge photographs of her family, and he saw that she recognized them when facial-processing centers in her brain ignited on-screen. When she was shown nonsense images with similar colors, these regions of her brain lay dormant. Dr. Owen performed additional PET scans over the coming months, and they showed that she was becoming more aware all the time.
"Not being able to communicate was awful—I felt trapped inside my body," Kate said. "I had loads of questions, like 'Where am I?', 'Why am I here?', 'What has happened?' But I could not ask anyone—I had to work it all out."11 She formed nightmarish theories to try to make sense of it all. "I thought I was in prison and I had forgotten how to move."12
But the PET scans changed all that, she said. "They found I was there inside my body that did not respond."13 She credits the scans for hastening her recovery, for giving her hope, and for encouraging others to interact with her. It took two years before she regained full consciousness. Now she uses a wheelchair, but she can communicate using a keyboard and she can read, use the computer, and play board games without help.
Her parents agree that Dr. Owen's discovery was a critical piece of news. "The scan meant an enormous amount to us," her father said. After the test, "the doctors were able to tell us for the first time that Kate's brain was processing things. That was a big breakthrough and it meant when we were doing things with her—talking to her, showing her pictures, writing her notes—we felt, even if she didn't understand, her brain was processing things. We realized something might be there to help her to cope with this horrendous experience she was going through."14
When she was told the news that the Cambridge team had discovered what was apparently normal brain activity in another "vegetative" patient, Ms. Bainbridge observed, "I think the work Dr. Owen is doing is so important. I can remember how awful it was to be like I was. It really scares me to think what could have happened if I hadn't had the scan."15
When hope is in vain
The journal Science, when it published the remarkable fMRI findings, cautioned that they must not be taken as typical. The editors included a special note in their press release about the study, mentioning the controversial Theresa Schiavo case and stressing that the new research "should not be used to generalize about all other patients in a vegetative state, particularly since each case may involve a different type of injury."16
What about Theresa Schiavo and her heart-wrenching case? Few end-of-life stories have polarized a country the way hers did, and some who followed it might wonder if the results of this new study call her diagnosis as permanently vegetative into question. Was there ever any reasonable hope for Theresa's recovery?
Decidedly not, say neuroscientists asked to comment, noting that her brain was deprived of oxygen for much too long. By the time paramedics arrived to resuscitate her heart and breathing, her brain was already severely, irreparably damaged. All seven board-certified neurologists who examined her agreed that she was permanently vegetative—that the thinking, feeling part of her brain had died. "As such," says neurologist Eelco Wijdicks of the Mayo Clinic College of Medicine, "she could never have recovered to an independently functioning human being, able to care for herself."17
Despite consensus among neurologists who examined her, Ms. Schiavo's health was described a number of ways—many of them erroneous—as the public debate raged around removal of her life support. Some neurologists near the end of her life suggested that she might be minimally conscious, whereas other commentators described her as brain dead or, at the other end of the cognitive spectrum, as a victim of locked-in syndrome (LIS), a condition in which there is severe damage to the brainstem but the cerebral cortex is unaffected. A person with LIS can think and feel emotion just like a healthy person, but cannot move or communicate except by blinking.
What role did brain scans play in her diagnosis? Dr. Ronald Cranford, who examined Theresa in 2002, performed a computed tomography (CT) scan of her brain. CT technology takes a series of two-dimensional x-ray images and compiles them, through computer algorithms, into three-dimensional images.* Dr. Cranford reported that the scan showed little else than scar tissue and spinal fluid. He also performed an electroencephalogram (EEG), a diagnostic test to record electrical impulses (brain waves) associated with mental activity. The EEG showed no sign of life in the thinking parts of her brain.
"It's totally flat—nothing," Dr. Cranford said, "and this is very unusual. The vast majority of people in a persistent vegetative state show about 5 percent of normal brain activity."18
The autopsy report, released in June 2005, backed the neurologists' diagnosis. "This damage was irreversible," the medical examiner said of the injuries to her brain, which had shrunk to half its normal size. "No amount of therapy or treatment would have regenerated the massive loss of neurons."19