Vegetative patients show brain activity, awareness

Researchers publish a groundbreaking yet preliminary study that, with the help of MRI scans, finds 17 percent of patients thought to be vegetative exhibit normal brain activity.

It all started in 2006, when researchers were studying a young woman considered to be in a vegetative state. Using MRI to scan her brain, they asked her to imagine herself playing tennis and touring her own home, and found that her brain behaved in much the way a normally functioning brain does.

The neuroscientists were shocked into action as news of what may have only been an anomaly prompted families to ask that the researchers study their own loved ones, too.

One of the neuroscientists, Adrian Owen at the University of Cambridge, alongside colleagues at the University of Liege in Belgium, have just published the results of their initial research on 54 patients--23 thought to be in vegetative states and 31 to be minimally conscious--in the New England Journal of Medicine on Wednesday.

While the majority of the patients exhibited no brain activity via MRI scans , four considered to be in vegetative states did and one thought to be minimally conscious did. Three of these five patients actually showed signs of awareness during intensive standard bedside tests, while two did not.

Functional MRI scans of a healthy control subject and five patients with traumatic brain injury show activations associated with the motor imagery as compared with spatial imagery tasks (yellow and red) and the spatial imagery as compared with motor imagery tasks (blue and green). New England Journal of Medicine

Moreover one of the patients, a 29-year-old in Belgium asked to answer questions indicating "yes" by thinking about tennis and "no" by mentally touring his own home, answered every single question about his life--from his father's name to whether he had siblings--correctly.

"He could produce no communication with his body, but he could systematically and repeatedly change his brain activity to indicate 'yes' or 'no' with 100 percent accuracy," Owen says. "These are patients who are totally unable to perform functions with their bodies--even blink an eye or move an eyebrow--but yet are entirely conscious. It's quite distressing, really, to realize this."

There are some 20,000 Americans thought to be in vegetative states, which means that even if doctors make the correct diagnosis 99 percent of the time (in Owen's study the percentage was found to be 83), some 200 "vegetative" Americans may be conscious, cases where "trapped" may in fact be a more accurate description.

But those who immediately think of the most publicized case--that of Terri Schiavo, whose family had an extremely public dispute over whether to continue care--should know that Owen warns that much more research with greater sample sizes is needed before any broad conclusions can be made. In addition, he and other experts point out that this research does not apply to worse brain trauma cases than those they studied, such as the severe oxygen depletion that resulted when Schiavo's heart stopped.

Still, Schiavo's brother Bobby Schindler tells the Washington Post that the study demonstrates the limits of medicine in providing accurate diagnoses: "I wish this could have been used on my sister to see what could have been done to help her."

One can't help but feel for Schindler, and yet he is off the mark when he says this study demonstrates the limits of medicine; more specifically, it demonstrates the limits of humans in making bedside diagnoses based on outward signs, but it also highlights the progress of increasingly sophisticated brain scanners in helping us see what is actually going on inside our brains.

Additional research could begin to explain the great mysteries of human consciousness, not to mention allow doctors to communicate with those patients who demonstrate brain activity, as may have happened recently --also in Belgium. But how certain will we need to be that these patients are conscious enough to make such profound decisions as whether they want to stop their own care?

"If a patient wanted to die, could they explain themselves adequately?" asks Joseph Fins, chief of the division of medical ethics at the Weill Cornell Medical College. "If they say 'yes,' what does that mean? If this person said 'yes' but meant 'maybe' or it was 'sort of yes,' we may not be able to understand that sort of nuance. You have to be very careful."

The possibilities and consequences of this research will likely result in a range of questions that are certain to weigh heavily on caregivers and family members in the wake of brain injuries and illnesses.

In the meantime, one might consider having another look at one's will.

 

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