Buried alive in your own skull.
The wheels lock, the car skids, you see the 18-wheeler heading for your windshield. You have just enough time to open your mouth. Then the bite of glass and metal, and merciful blackness.
Somebody's talking. You try to open your eyes, but nothing happens. You can't move or feel anything. In the murmurs around you, you make out a few words: prognosis, unresponsive, permanent. They keep talking about somebody who's here, somebody who never speaks and is never spoken to.
A child cries. You've heard that cry before. Out of the blackness, the thought comes at you, engulfing you: The unspeaking person is you. You're dead. And then a more horrible idea: Maybe you're not.
You try to call out, to scream. No one knows you're here, awake inside your skull. No one will ever know.
That nightmare is no longer science fiction. Five days ago, Science published a report on a young woman devastated by a car crash in England. For five months after the accident, tests showed no signs of awareness. Doctors declared her vegetative. 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.
How rarely does this happen? Until a decade ago, FMRI didn't even exist. According to the authors, 60 other vegetative patients have been tested on it and have flunked. The English patient had several factors in her favor: Her injury was traumatic, her brain was largely intact, and she had been vegetative for only a few months. At the other end of the spectrum are people such as Terri Schiavo. Their injuries are caused by oxygen starvation, their brains are liquefied, and they've been vegetative for years. By various estimates, 25,000 to 35,000 Americans have been diagnosed as vegetative. How many of them have received FMRI scans? How many would light up? How many are awake in there?
The scientists who studied the English patient report that in the five months after her injury, "No elaborated motor behaviors, which are regarded as 'voluntary' or 'willed' responses, were observed from the upper or lower limbs. There was no evidence of orientation, fixation greater than 5 seconds or tracking to visual or auditory stimuli. No overt motor responses to command were observed." In short, she was "unresponsive." She met the standard for a vegetative diagnosis, displaying "no reproducible evidence of purposeful behavior." In an analysis that accompanies the study, a French neuroscientist notes that she repeatedly failed to "manifest" such behavior.
Then they put her in the machine and gave her the imagination test. Result: "Significant activity was observed" in key brain areas. She managed "to respond to [commands] through her brain activity, rather than through speech or movement. Moreover, her decision to cooperate with the authors by imagining particular tasks when asked to do so represents a clear act of intention." According to the attached analysis, her "patterns of brain activation" suggest "an active mental performance."
Nothing about the patient changed. What changed was the test—and with it, our definitions of evidence and activity. Before the scan, "behavior," "response," "action," and "performance" were things done by your visible body. To be "manifest," "observed," or counted as "evidence," they had to be external. By making the brain's blood flow observable, the scan expanded our understanding of physical reality and human agency. Thought is activity. Imagination is performance. Intention, which used to be defined as separate from action, is now an "act of intention."
Will Saletan covers science, technology, and politics for Slate and says a lot of things that get him in trouble.
Photograph of brain scans on Slate's home page by Lawrence Berkeley National Library/Photodisc Green.