Neuroscientist Adrian Owen is developing techniques to determine if patients in vegetative states are conscious or not. Owen predicts that about 20% of people in these vegetative states are ‘locked-in’ but are actually capable of communicating. As misdiagnosis in consciousness disorders is approximated around 40%, developing techniques to communicate with these patients has profound implications for improved quality of life following a coma and can potentially help family members known when it is time to say good-bye.
In 2010, Owen and others at the Medical Research Council Cognition and Brain Sciences Unit in Cambridge, United Kingdom and University of Liège in Belgium reported that using fMRI and specific questions, 5 out of 54 patients were able to purposely modulate their brain activity and three demonstrated at least slight awareness. The research team placed each patient into a functional magnetic resonance imaging (fMRI) machine and measured changes in blood-oxygenation levels during various mental-imagery tasks. This was the first report of communication with a patient believed to be in a vegetative state.
fMRI measures brain activity by assessing changes in blood flow throughout discrete areas of the brain. Blood flow is related to brain cell energy expenditures and is measured by the changes in the magnetization between oxygen-rich and oxygen-poor blood. Imagining certain events or activities, like playing tennis or walking through the rooms of your house, results in a predictable changes in blood-oxygenation levels in specific brain regions in healthy human subjects. When asked by Owen to imagine playing tennis or walking through the rooms of her house, a vegetative woman unresponsive for five moths after a traffic accident displayed similar blood flow changes as healthy volunteers, suggesting that the women was conscious and able to understand what types of events she was supposed to be imagining. The researchers later went on to instructing: ‘imagine playing tennis for yes, and navigating the house for no.’
From a NatureNews article by David Cyranoski, “Owen takes a practical approach to applying the technology, hoping that it will identify patients who might respond to rehabilitation, direct the dosing of analgesics and even explore some patients’ feelings and desires. “Eventually we will be able to provide something that will be beneficial to patients and their families,” he says.”
The original findings have now been replicated using an electroencephalogram, a faster, cheaper but less precise tool. Cyranoski explains, “Now, using an EEG, Owen is planning to study 25 people in a vegetative state every year. He will have the help of a new ‘EEGeep’, a jeep equipped with experimental equipment that will allow the researchers to travel around to test patients who cannot be transported to Western Ontario.”
Of course, Owen’s new technique raises important ethical issues. Which questions should be asked of patients, what qualifies as giving informed consent, and the potential to give loved ones a false sense of hope are just some of the issues. Additionally, there is a large number of researchers who do not believe that these individuals are demonstrating consciousness. Owens says, “I got two types of e-mail. People either said ‘this is great’ or ‘how could you possibly say this woman is conscious?’.” But Kate Bainbridge, a young women diagnosed with being in a vegetative state following recovery from a viral infection and subsequent coma believes. Following successful rehabilitation as a result of Owen’s discovery that she had significant brain activity, she wrote, “It scares me to think of what might have happened to me if I had not had mine. It was like magic, it found me.”