One of the most vexing emotional and ethical issues in all of medicine is the decision by family members to “pull the plug,” that is, to take a severely ill, non-communicate relative off of the life-support systems keeping him or her alive.
What makes this decision so hard, of course, is, absent a really clear statement ahead of time from the patient about end-of-life wishes, family members basically have to guess. But there may be – not yet, but someday – a way to make this agonizing guesswork a bit easier, thanks to a stunning series of recent experiments by Adrian Owen, who holds the prestigious Canada Excellence Research Chair in cognitive neuroscience and neuroimaging at the University of Western Ontario.
The recent work by Owen, and others, using fMRI brain scanning technology shows that some patients diagnosed as being in a persistent vegetative state may actually have some degree of consciousness and be able to communicate, that is, by sheer thinking, be capable of answering comparatively simple questions such as “are you in pain?” (Obviously, that’s a much simpler question than “do you want to die?”)
The particular patient generating the latest excitement is 39-year old Scott Routley who, 12 years ago, had a car accident that left him with a severe brain injury. By standard tests, doctors thought he was in a persistent vegetative state, or PVS.
A quick primer here. There are various degrees of consciousness. In a coma, a patient looks asleep – the eyes are closed, the person doesn’t move and tests with an EEG (electroencephalograph) look much like the brain of someone under general anesthesia.
A persistent vegetative state is different. The patient’s eyes are open, he or she has regular sleeping and waking cycles and may actually look around, not really “at” anything, but with a so-called “roving gaze.” The person may even have REM, or dream, sleep stages. PVS is so confusing to onlookers – and doctors – that if a group of people watched a video of such a patient, half would say the patient was conscious and half would not. While a coma may last only briefly – as when someone gets whacked with a baseball bat – a vegetative state can last for years. If someone does recover from the vegetative state, at best he or she will be severely disabled.
In between PVS and severe disability is the so-called minimally conscious state (MCS). If you ask minimally conscious people to move a hand or look somewhere specific, they do so often enough that it’s clear they are responsive, while a PVS patient can never do that. (All these states, by the way, are different from “locked-in syndrome,” in which a person is fully conscious and cognitively intact but is unable to move except, in some cases, to blink their eyes to communicate.)
After his accident, Scott Routley couldn’t communicate and the usual tests showed no signs of awareness. Owen, who told me he has believed for 15 years that some PVS patients like Routley are “actually conscious but can’t show it.” Owen is now convinced that Routley is “definitely not” in a persistent vegetative state. (He has also documented Routley’s responsiveness with an EEG, a simpler technology than fMRI.)
Essentially, Owen trained Routley to answer questions through a kind of game. When he asked Routley to imagine himself playing tennis, a particular part of his brain, the premotor cortex, lit up on the fMRI brain scans “with a very big signal.” (The premotor cortex sends signals to the motor cortex, which actually signals muscles to move.) Routley learned that imagining to play tennis, thus lighting up this part of his brain, meant “yes.”
Owen then trained Routley to imagine himself walking through a familiar house from room to room. When Routley did this, a totally different part of his brain lit up, the parahippocampal gyrus, which helps people navigate through space. Routley learned that imagining this activity meant “no.” In a series of sessions, Routley was able to correctly answer questions like “Is the sky blue?” “Are bananas yellow?” convincing Owen that Routley could communicate “yes” and “no.” He then asked Routley if he was in pain, and Routley answered “no.” Routley was also able to show that he knew he was in a hospital, that he knew the year of his accident and knew what the current year was. “This guy is conscious, he just clinically appears vegetative,” Owen told me.
I think this is fabulous. And scary. It would be wonderful to know what an uncommunicative relative really wants. And terrible to depend too much on technology that, like the humans who invent it, might be wrong. And so far, none of this means that doctors should perform fMRIs on everyone with severe brain injuries, says Robert Truog, a professor of medical ethics, anesthesia and pediatrics at Harvard Medical School. But it could provide a way, Truog says, to ask some severely brain-damaged patients whether they value their life as it is “before we would make a decision to give comfort measures only.” I agree we should proceed, but with caution. More importantly, so does Owen. “I don’t think we should ask someone if he wants to live because we can’t do anything about it – there is no legal framework that supports euthanasia,” he said. But that legal framework may already be in the works.
But before he could say more, he had to get off the phone: The lawyers were calling.
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