A 29-year old Belgian man who spent five years in a vegetative state, has answered simple question with ‘yes’ and ‘no’ using an MRI-scanner, a study published on the website of the New England Journal of Medicine on Wednesday showed. Scientific response to the finding was mixed. Some researchers say this find heralds a new era of increased autonomy for patients suffering from reduced consciousness, but others argue the discovery is of little consequence.
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The 29-year old was part of a larger study of vegetative and minimally conscious patients who had been left comatose by massive brain trauma. Vegetative patients commonly awake within weeks to open their eyes, move their feet or scratch their hands. Some may even suddenly sit up in bed, but their motor activity is always limited to reflex actions. Vegetative patients do not respond to stimuli like light or sound. They may be awake, but they are not conscious.
Communicating through brain scans
In 2006, the same group of scientist had already demonstrated that, a 23-year old female victim of a traffic accident was able to respond to spoken commands. When the woman was asked to picture herself walking through her apartment, areas of the brain involved in spatial orientation lit up. When the researchers asked her to picture herself playing tennis, parts of the brain associated with motor coordination were activated. The women’s brain activity, as registered by the scan, differed little from that of normal healthy people.
In their latest research, the scientists studied 23 patients who did not respond to stimuli and 31 who did so only occasionally. Five proved able to respond to commands like the 23-year old woman. According to Steven Laureys, one of the scientists involved in the study, the patients who responded to commands all suffered their brain trauma in accidents. The study group did not find any evidence whatsoever patients whose brain was damaged in a stroke were also able to communicate through fMRI scans.
The scientists asked a single patient, a 29-year old man who suffered a traffic accident five years ago, specific questions like: "Is your father’s name Thomas?" and "Do you have any brothers?" The patient was told to respond by either thinking of tennis or walking through a house. “Before we put him in the fMRI scanner, a small army of experts tested him every month. None of them were able to reach him, so they concluded he was in a vegetative state. Using our fMRI, he answered five out of six questions correctly. He did not give a clear answer to the sixth question,” Laureys said.
The only way to talk
So far, communicating with the patients in any other way has proven impossible. According to Laureys, that might change. The Belgian neurologist said he hoped to give patients a voice by registering electrical activity in their brains. “We are at the dawn of a new era. These vulnerable patients will one day enjoy more autonomy and be able to make everyday decisions again,” Laureys said.
Nicolas Schiff, a neurologist at Cornell University not involved in the study called the results “spectacular”. “The fMRI is only a diagnostic tool that we can use to find patients who are ready for new ways of communicating. They can no longer be considered vegetative. That is hugely important progress,” he said.
“All our traditional tests are meant to elicit a motor response. Like, ‘pinch my hand’ or ‘blink your eyes to say yes’. But these test often fail to yield clear results. Approximately 40 percent of patients are misdiagnosed. The fMRI gives us an additional diagnostic tool,” Laureys added.
Some are unconvinced
Other scientist remain to be convinced. Rien Vermeulen, a neurologist at Amsterdams’ AMC hospital, for instance. “I am not surprised they found brain activity. You regularly find small clusters of active brain cells in these patients, but what does that mean? Does the patient experience consciousness? Responses like these can also be elicited when someone is unconscious,” Vermeulen said.
A third expert, Geraint Rees, said he felt “genuinely torn,” by the study’s findings. “We are talking about young people who live in heartbreaking conditions here. For decades there was little scientific interest in these patients. Now at least we have a tool to study their consciousness. They can change their brain activity to answer some of the questions correctly. That means they have some residual comprehension left,” Rees said. “Still, it is a far leap from answering a few simple questions to being aware like you or me, after all they are severely brain damaged.”