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How scientists can now read the minds of the 'living dead'

A man who was presumed to be in a vegetative state for five years has answered questions using his thoughts alone in a ground-breaking experiment.

The breakthrough promises to allow some patients who are "locked in" by brain injuries to communicate.

The 29-year-old Belgian was able to reply to simple yes/no questions, such as "is your father's name Alexander?", by changing his brain activity.

Scientists then read his answers by studying functional magnetic resonance imaging (fMRI) scans.

He had previously failed to show any signs of consciousness after suffering a severe brain injury in a road accident. A vegetative state (VS), in which patients wake from a coma but appear to have no awareness, had been diagnosed.

The remarkable results, from British and Belgian researchers, suggest that at least some VS patients are able not only to hear and understand people, but also to respond mentally in ways that can be harnessed for communication.

The case echoes that of Rom Houben, a 46-year-old man who was trapped in his body unable to communicate for 23 years until a neurologist at the University of Liege, and one of the authors of today's study, used a brain scanner to show that his brain was still functioning. He is now communicating using one finger and a touchscreen on his wheelchair.

"It's very possibly the case that we will get into a situation within 10 years where patients incapable of any response are able to communicate using their brain alone on a day-to-day basis," said Adrian Owen, of the Medical Research Council (MRC) Cognition and Brain Sciences Unit in Cambridge, a leader of the research.

The advance, however, raises difficult ethical questions, such as whether patients could use the technology to express a wish to die. While they may be able to answer yes/no questions, their brain damage may mean they lack the capacity to give informed consent to life-or-death decisions.

"An obvious question you might ask is whether you want to be kept alive, but there are ethical and legal hurdles that need to be crossed to determine whether a patient has the cognitive wherewithal to make decisions like this for themselves," Dr Owen said. "You can't do that on the basis of these results for one gentleman."

He said that the findings, which are published in The New England Journal of Medicine, had been a comfort to the patient's relatives. "One of the most difficult things in this situation is not knowing whether you're getting through, whether your loved one can understand you," he said.

He emphasised, however, that not every patient in a vegetative state is aware. Of 23 who have been scanned with fMRI so far, only four have been shown to retain clear signs of consciousness.

The research, which was also led by Steven Laureys, of the University of Liege, and Martin Monti, of the MRC unit, builds on a study published in 2006 in which the team found that a 23-year-old woman who seemed to be in a vegetative state was conscious.

The team now plans to repeat the experiment. The next goal will be to refine the technique to allow patients to communicate routinely, rather than only when inside a fMRI scanner.

hnews@herald.ie


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