Could you try an experiment with me? Picture that you have fallen asleep, and wake up to find yourself in an empty white room with white walls, separated from the rest of the world by a thick glass wall. Occasionally your family and friends stop by to look at you through the glass. There are some other people you don’t recognize, but you figure they are doctors and nurses. You can hear them, and see them, but they can’t hear or see you, no matter how hard you try. Frustrating? Yes. Frightening? Probably.
I’m using this thought experiment to describe the reality of some people with a severe brain injury. They have been diagnosed as being in a persistent vegetative state, or PVS.[1] PVS patients have regular cycles of sleeping and being awake, but they are not aware of their surroundings or others. Their physical movements are reflexes, not purposeful actions.
At least, that’s what we’ve thought.
While we can’t know for certain what PVS patients experience, a recent study raises questions. Groundbreaking research conducted by international teams in Belgium and Britain studied people with PVS.[2] They used functional MRI, a sophisticated brain scan, to measure the patients’ responses to a series of controlled questions. If the answer to a question was “yes,” the patient was directed to imagine being in a room in their home. If the answer was “no,” they were to picture themselves playing tennis, which activates a different part of the brain.
What did the researchers discover? It was stunning. Of the 54 patients, 5—or about 10 percent—answered the yes/no questions, showing measurable brain activity, even though they could not respond with visible physical movement. When the questions were reversed, so was the area of brain activity that showed up on the MRI.
These surprising findings have been confirmed by other studies.[3] Some of these patients may be aware of us. We just can’t “hear” or “see” through the glass wall of their brain injury.
Other studies are important, because they suggest that about 40% of the time, the PVS diagnosis is incorrect. We may have unintentionally harmed some people who are aware, but unable to communicate with currently available technology. As Christians, we know we must treat these people with care, as if they were conscious and aware of us. Who knows, perhaps one of them is?
Think about it.
[1] There is a debate about the wisdom and appropriateness of using “vegetative” in describing human patients. Some consider it dehumanizing.
[2] Benedict Carey, “Trace of Thought Is Found in ‘Vegetative’ Patient.” New York Times, February 3, 2010. http://www.nytimes.com/2010/02/04/health/04brain.html (accessed February 25, 2010).
[3] Katherine Harmon, “Conditional Consciousness: Predicting Recovery from the Vegetative State.” Scientific American, September 20, 2009. http://www.scientificamerican.com/article.cfm?id=conditional-consciousness (accessed March 1, 2010). This study used a simple tone and puff of air to detect whether unresponsive patients may be capable of simple learning, a technique similar to Pavlov’s dog experiments. Learning is a sign of consciousness, and can predict whether the patient will recover. The patient’s response to the tone and puff of air did not seem to match their medical diagnosis. Some responded better than their diagnosis; others did worse. But the test was 86% accurate in predicting recovery.