Then, scientists put her in a Functional Magnetic Resonance Imaging scanner, which tracks blood flow to different parts of the brain. They asked her to imagine playing tennis and walking through her home. The scan lit up with telltale patterns of language, movement, and navigation indistinguishable from the brains of healthy people. Something was awake inside that woman's skull. Without the scanner, no one but her would have known.
Now scientists are debating what goes on in the English patient's head. Some call her performance a "decision"; others dismiss it as a mere "response." They ask why her body doesn't move, since her motor pathways appear to be preserved. The analysis in Science concludes that she has a "rich mental life" but may not be "conscious." What in God's name does that mean? Would you pull the plug on a 24-year-old relative with a rich and responsive but unconscious mental life? Go ahead, raise your hand. Or just think about raising it, and we'll record your vote by brain scan.
Saletan gives the obligatory comparison to Terry Schiavo (starved of oxygen for years, her brain had "liquefied") and raises the issue that "the reality of your mental life" may depend on which tests you or your insurer can pay for, which hospital you're taken to.
This kind of stuff scares the shit out of me, though I know it's unlikely that MS could put me in a similar situation. But in darker moments, when I've been out in the sun too long and lost my ability to walk and peed my pants and been reduced to a lurching, mumbling pile of meat and bones, I feel utterly disconnected from the corporeal existence that I used to know. Increasingly, I find myself drifting in and out of this disconnected state; the discombobulated state sometimes feels more ordinary than the flares of physical and mental vitality.