Science-- there's something for everyone

Sunday, February 21, 2010

Unlocking locked-in syndrome

Locked-in syndrome is a tragic condition in which a brain injury robs a person of the ability to move or communicate in any way. Often doctors and family members cannot ascertain whether the patient is aware at all, or is completely vegetative. In the cases where doctors suspect that the patient is at least partially conscious of his surroundings, it has been a frustrating struggle to try to find ways to communicate with the patient.

Recently, Adrian Owen of Cambridge, Steven Laureys of the University of Li├Ęge in Belgium, and other neurologists may have found a key to locked-in syndrome.

The doctors performed functional magnetic resonance imaging (fMRI) scans of 54 patients who were in either a vegetative state (no apparent awareness) or a minimally conscious state (occasional episodes of cognitive behavior). None of the patients had been able to communicate prior to these experiments. While hooked up to the scanners, the patients were asked to imagine themselves playing tennis, or walking around their own apartments. Because these two scenarios were expected to activate different parts of their brains, the doctors hoped they would able to detect whether the patients were in fact aware.

Five of the patients were able to understand the instructions and conjure up the correct images in their minds, as seen by the scans. One patient was even able to use the fMRI system to communicate. By thinking of playing tennis for ‘yes’ and walking around the apartment for ‘no’, he was able to answer a series of questions.

Although this technique is impractical for any meaningful two-way communication, it could be used to assess the consciousness of locked-in patients. I believe it was suggested on The Skeptics’ Guide to the Universe that patients might also be able to take greater charge of their own care by indicating whether they approved of certain procedures.