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State of MindNew research may help unlock vegetative and minimally conscious patients.

By Ford VoxPosted Thursday, April 23, 2009, at 7:10 AM ET

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Schiff's theories have shown promise in the past. He's one of the players behind a dramatic trial of deep brain stimulation in 2007, which applied pacemaker stimulation, already used for Parkinson's and essential tremor, to an MCS patient's central thalamus. During rehabilitation, our therapists gave Joshua median nerve stimulation, a poor-man's alternative to DBS; he withdrew and grimaced. His apparent discomfort was a good sign, but he was well short of regaining speech, which occurred in the DBS trial.

Now, Schiff and his international team, supported by a landmark $3.9 million grant from the James S. McDonnell Foundation, are in a quest to accurately diagnose patients like Joshua. The grant recognizes that it's at least as important to find out if people are conscious as whether they're dead. And Schiff has assembled a consciousness dream team, including Steven Laureys at the University of Liege in Belgium and Adrian Owen of Cambridge, to make it happen.

In a 2006 Science report, Owen analyzed the real-time brain activity of a woman in a vegetative state five months after a vehicle accident. The 25-year-old, whose only response to the external world consisted of occasionally fixating on an object, was able to follow complex commands to imagine doing things like playing tennis or walking through the rooms of her home. Eleven months after her scan, the virtual tennis star began a visible recovery, and Owen has gone on to find similarly remarkable results in at least three more of the 40 patients he has studied to date.

Yet the collaborators' most revolutionary work may be in a cheaper, more portable technology than fMRI and other enormous, multimillion-dollar scanners that can't attach to an electric wheelchair. Andrea Kübler first described the concept of using brain-computer interfacing, driven by the brain's EEG waves, to diagnose patients with disorders of consciousness.

They're great for detecting seizures and sleep, but what can an EEG tell us about the brain's most significant function—consciousness? Until recently, the brain's analog wave seemed to pale in comparison with the diagnostic and prognostic powerhouse that is the heart's EKG. But digitally processing the EEG makes it possible to capture unique, reproducible signals—that's all you need to control a computer. Rudimentary commercial versions are entering the market—like one that will let you levitate a ball. We'll find therapeutic uses for these brainy toys almost as fast as the Wii.

In November, Laureys' group demonstrated that, as Kübler predicted, some low-level MCS patients who could seemingly only visually fixate or track for brief periods were able to follow basic instructions. In this case, they counted familiar and unfamiliar names played randomly into headphones—enough to prove low-level awareness but not enough to communicate. But Laureys is about to open a new frontier for BCI as a diagnostic tool. Using the BCI protocol, Laureys says he has found that some clinically vegetative patients are conscious.

So far, every case of digitally uncloaked consciousness has occurred within six months from injury. Still, I can make out Joshua's thalami, such as they are, on his MRI. Do they need a jump-start? Could BCI help us guide cognitive therapy or tell us more about how he's responding to stimulants? Many doctors harbor a therapeutic nihilism about these patients, but this research should give us good reason to keep our minds open. Even as we talk, Joshua's mother administers a range of motion therapy to her son's outstretched arm. She wants his body to be ready if his mind comes back.