Neurological Rescue Mission: Communicating with Those Trapped within Their Brains

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Last week, it also emerged that Houben's case was not an isolated one. Cambridge University neurologist Adrian Owen and Laureys jointly performed brain scans on 54 VS and MCS patients. The procedure, known as functional magnetic resonance imaging (fMRI), shows which areas of the brain are active in real time.

Patients were asked to imagine themselves playing tennis or walking around in their own familiar apartments. Imagining each of these activities activates a different part of the brain.

Five of the 54 patients proved to be able to call up each scene when prompted. One patient was even able to answer questions using this technique: When asked questions -- such as "Do you have brothers?" "Is your father's name Thomas?" or "Is his name Alexander?" -- he was asked to think of tennis for "yes" and the apartment for "no." The correct brain region lit up every time.

This particular man is 29 years old and, like Houben, the victim of a traffic accident. For seven years, he lay in a vegetative state -- inaccessible. Even after his spectacular messages delivered with the help of the MRI machine, researchers still found no outward signs of consciousness. A thorough behavioral test elicited no reaction whatsoever from him. Indeed, he appears to be completely trapped within his own brain.

The study, which was published in the New England Journal of Medicine, provoked a global sensation. Although, such extreme cases occur only very rarely, the possibility can no longer be ruled out for any patient in a similar state.

So far, only an fMRI machine can offer any certainty. "But a single machine costs €4 million ($5.5 million) and weighs five tons," says Birbaumer, the brain researcher in Tübingen. "That's no help at all for everyday life in a nursing home or at home."

Searching for Other Ways to Communicate

In any case, the procedure is entirely unsuitable for Rom Houben in Belgium. One attempt ended without usable results because spasms make it nearly impossible for Houben to hold his head still. For him, electrodes that record brain waves -- like those used in Marie Bruno's experiments -- would be a more suitable method.

Bruno's first EEG studies of other vegetative patients in Liège returned reasonably encouraging results. Three of the 13 test subjects were able to answer her questions correctly often enough to make the results statistically significant. Nevertheless, the technique is still far from providing a reliable means of communication. Moreover, it's not easy to attach all the sensors in the right places and to precisely calibrate the electronic equipment. The electrode pads also have to be removed after a couple of hours so as to keep the damp skin beneath them from getting irritated.

Niels Birbaumer is hoping to get better results using dry electrodes that do not come into direct contact with the skin. Instead, they are simply placed on one's hair and can be worn for as long as desired. Still, at the moment, the signals these electrodes receive are still too unclear. "But in a year or two," Birbaumer believes, "the technology should be ready for the first experiments."

Of course, there already is one far better method, which involves implanting electrodes directly into the brain. This technique generally produces wonderfully clear signals, but it still has its risks. For example, there is a constant danger of infection, which could even be fatal in extreme cases. Under these circumstances, researchers face a difficult ethical dilemma. As Laureys asks: "Is it permissible to drill into the skull of somebody who's unable to give his or her consent?"

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• Part 1: Communicating with Those Trapped within Their Brains
• Part 2: Trapped Inside Your Brain