By Manfred Dworschak
Day after day, Marie-Aurélie Bruno attaches caps wired with embedded electrodes to her patients' shaved heads. The neuropsychologist at the University of Liège in Belgium is looking for signals in the quivering readouts of the brain's electrical activity, where there might be a hidden message.
The technique the group is using has its origins in the laboratory of Niels Birbaumer, a neurologist at the University of Tübingen in southwestern Germany. "It has worked out pretty well for us," he says of the treatment he uses on patients with "locked-in syndrome" -- that is, ones who are verifiably fully conscious but paralyzed from head to foot. With the help of electrodes, some patients are able to communicate via a computer. A variety of letters appear on the screen in quick succession. By briefly concentrating on the word "yes," the test subjects can indicate the desired letter. Sometimes they manage this within a few seconds; sometimes it takes a full minute.
The researchers in Liège hope this technique might be able help the man who has become their most famous patient. After a car accident, 46-year-old Rom Houben spent 23 years in a persistent vegetative state, with his remaining consciousness undetected. For him, this technique could be the only chance he'll ever have to communicate with the outside world.
Facilitated, but False, Communication
The staff at Houben's care center first tried an on-screen keyboard that he could operate using his right index finger, which is not fully paralyzed. For a while, it seemed like a good idea and, after some practice, Houben was able to type rather quickly. He made many mistakes, but his messages were understandable. Still, using that method required the assistance of a speech therapist, who stood behind him to support his hand.
At one point, Laureys, the neurologist, claimed that he had ruled out the possibility that it was actually the speech therapist doing the writing. But it turns out that his checks weren't quite thorough enough. Obtaining reliable results requires a rather protracted procedure. Patients with serious traumatic brain injuries are not always capable of following difficult instructions. They also sleep a great deal, and sometimes they sink into extended periods of delirium. In order to rule out false negative results, repeated tests need to be conducted over the course of several weeks.
Laureys has now carried out those tests, and his results hold that it wasn't Houben doing the writing after all. The tests determined that he doesn't have enough strength and muscle control in his right arm to operate the keyboard. In her effort to help the patient express himself, it would seem that the speech therapist had unwittingly assumed control. This kind of self-deception happens all the time when this method -- known as "facilitated communication" -- is used. (As a result, the things that Houben was attributed as saying to SPIEGEL for an article printed in November 2009 were also not authentic.)
In the more recent test, Houben was shown or told a series of 15 objects and words, without a speech therapist being present. Afterward, he was supposed to type the correct word -- but he didn't succeed a single time.
This doesn't necessarily discredit facilitated communication altogether. Laureys analyzed another paralyzed test subject who answered all 15 control questions correctly despite having a comparable brain-damage diagnosis. "That means it is really necessary to verify every single case," Laureys says.
Now the work with Houben will have to start all over again. But there is one thing for sure -- images taken of his brain activity reveal that it is behaving only slightly differently from that of a healthy brain. As a result, researchers are fairly certain that Houben is conscious -- and they find themselves in the desperate position of a rescue team trying to dig out a person from under the rubble.
Attempts to use a pedal, which Houben pressed with his right foot, had already failed before. He actually was able to press the pedal down, but spasms usually made him unable to lift his foot back up. "We'll simply have to find another way to him," Laureys says.
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