Months after her infection cleared, Bainbridge was diagnosed as being in a vegetative state. Owen had been using positron-emission tomography in healthy people to show that a part of the brain called the fusiform face area (FFA) is activated when people see a familiar face. When the team showed Bainbridge familiar faces and scanned her brain, “it lit up like a Christmas tree, especially the FFA”, says Owen. “That was the beginning of everything.” Bainbridge was found to have significant brain function and responded well to rehabilitation3. In 2010, still in a wheelchair but otherwise active, she wrote to thank Owen for the brain scan. “It scares me to think of what might have happened to me if I had not had mine,” she wrote. “It was like magic, it found me.”
Owen moved from visual to auditory tests — “up the cognition ladder, from basic sound perception, to speech perception and then to speech comprehension”. For example, he presented people in a vegetative state with phrases containing words that sound the same but have two meanings, such as “The dates and pears are in the bowl”. The ambiguity forces the brain to work harder and shows up in characteristic fMRI patterns in healthy people — if, that is, they are comprehending the words. One of Owen’s patients, a 30-year-old man who had been incapacitated by a stroke, showed the same pattern4. But not everyone was convinced that these signs pointed to comprehension. “Every time I would go to a neurologist or anaesthesiologist and say, ‘he’s perceiving speech’, they’d ask ‘but is he conscious?’.”
...Owen hopes one day to ask patients that most difficult of questions, but says that new ethical and legal frameworks will be needed. And it will be many years, he says, “before one could be sure that the patient retained the necessary cognitive and emotional capacity to make such a complex decision”. So far, he has stayed away from the issue. “It might be a little reassuring if the answer was ‘no’ but you can’t presuppose that.” A ‘yes’ would be upsetting, confusing and controversial.
http://www.nature.com/news/neuroscience-the-mind-reader-1.10816