A couple of years ago neuroscientist Adrian Owen, then worked at the University of Cambridge (UK), and his colleagues at the University of Liege (Belgium) for the first time in history were able to communicate with a person residing in a vegetative state.


Adrian Owen (photo by John Hryniuk).

The patient is at number 23 was in a car accident at the age of 24 years and by the time the experiment for five years he led a "vegetable" lifestyle. Scientists put it in the machine functional magnetic resonance imaging (fMRI) and began to ask questions.

The researchers are convinced that the answer was. The change of blood flow to certain parts of the brain of the patient is confirmed that the person is conscious and able to communicate.

Vegetative condition is usually seen in people coming out of a coma. Some parts of the brain start to function more or less normally: for example, people can gnash their teeth, grimace, randomly moving eyes. They sleep and awake. But no signs of consciousness, such patients do not show, and conventional wisdom says that they have damaged part of the brain is necessary for cognition, perception, memory and thinking. Often these changes are irreversible.

The results of the study, Mr. Owen made a splash. Many agreed that these patients may actually be at least in a state of minimal consciousness. The University of Western Ontario (Canada) immediately lured scientist allocating a $19.5 million to create a more reliable, cheap, accurate, portable method of communication with patients staying in a vegetative state, there in the world hundreds of thousands. If successful, people will have the opportunity not only to Express emotions, but to tell the doctor how to rehabilitation.

The work of Mr. Owen rooted in the late 1990s, when he was asked to write a review of clinical application of neuroimaging technologies. Scientist have discovered that the brain scan is only used to confirm the results of studies on the brain mapping.

He and his colleagues got a chance to fix the situation in 1997. The 26-year-old Keith Bainbridge was in a coma as a result of infection. A few months later after the body of the patient cleaned from viruses, coma changed vegetative state. Earlier using positron emission tomography Mr. Owen showed that in healthy people at the sight of a familiar face is activated so-called peritonealny the front part of the brain. Researchers have demonstrated Ms. Bainbridge pictures of familiar people, and her brain began to Shine like a Christmas tree. Thus it was proved that the patient is not in a vegetative, and in minimum state of consciousness. For this experiment was followed by rehabilitation, and in 2010, Ms. Bainbridge have been able to thank Mr. Owen personally.

Soon after the scientist moved with visual tests for hearing - went up on cognitive stairs. The fact that this step was very close to speech recognition. Mr. Owen suggested healthy people ambiguous phrases, and evidence that they have caught different values, was the increased activity of the brain. The same effect was registered in the brain 30-year-old man with a history of stroke. But not all were convinced that these signs indicate the understanding and stay in the mind. Then Mr. Owen made a different experiment.

In June 2006 he was placed in the tomograph 23-year-old woman in a vegetative state. The expert asked her to imagine how she plays tennis and going from room to room in your house. In healthy people, in consciousness, there has activated the motor area of the motor cortex, and the thought of moving around the house and adds gyrus of the hippocampus, located right in the center of the brain. A woman who had no contact with the outside world, for five months after a road accident, demonstrated strikingly similar pattern of brain activation.

But this did not convince colleagues. Some researchers consider it not a sign of consciousness, and something involuntary kind of knee-jerk reactions. Psychologist Daniel Greenberg of the University of California in Los Angeles (United States) said that the unconscious brain activity was caused by the order contained in the request of Mr. Owen.

I had to continue. Together with the neurologist Steven Lariam of the University of Liege Mr. Owen showed that of the 54 patients who were in a vegetative or minimally conscious state, five reacted the same way. Four of them were in a vegetative state.

The researchers then complicated the task: imagine a game of tennis, if you want to answer "Yes", and walk through the house in case no. After that, patients number 23 were asked questions, answers to which the technicians did not know. Your father's name is Thomas? No. Your father's name Alexander? Yes. Do you have brothers? Yes. Do you have a sister? No.

The experiment was not easy. The patient had to concentrate within 30 seconds, then-same relax. Then the same question was repeated again and again.

The patient responded correctly on five of the six questions. In response to the sixth was not registered any clear signals.

Specialist neuroimaging Russell Poldrack from the University of Texas at Austin (USA) considers Mr. Owen genius. And, say, a clinical neuroscientist Paraskev Nachev from Imperial College London (UK) criticizes the work of colleagues, Recalling that in some cases (for example, during epileptic seizures specific type) patients respond, without regaining consciousness.

Mr. Owen agree that consciousness is a thing more complex switch. It's not just "on" or "off". The presence of reaction in certain areas of the brain does not mean the presence of consciousness. But he is confident in his experiments were activated quite a large number of areas in order to qualify reaction as conscious. For example, you need to activate long-term memory to imagine playing tennis, and at the same time short-term, not to forget the question and conditions of the answer.

In any case, the line is so thin that with the same success can be argued both that and another.

Getting canadian grants, Mr. Owen tried to repeat the results of fMRI using electroencephalography (EEG), but lacked the resolution. Then the patients were proposed tasks easier - for example, to imagine how they wiggling toes. Repeating alarms give an accurate representation.

EEG was chosen due to the fact that this method is cheap, relatively portable and quick (millisecond delay in comparison with 8 - fMRI), that is, the research team has time to set 200 questions in 30 minutes. Enough to get lasts 175-190 the same answers to the same question that the results did not look accidental.

Now Mr. Owen plans to explore for the year up to 25 people in a vegetative state. He developed specially equipped jeep, where you can pay a visit to the home of the patient.

Will reveal signs of other systems - for example, responsible for smell and taste. For example, the patient presents itself as sucking a lemon, which can lead to changes in pH levels in the mouth and a corresponding signal to the brain. Experiments in healthy people has allowed to reveal what happens in the brain when recognizing jokes; soon the same will happen with patients.

Mr. Owen plans also to understand how deep intellect "people-plants". He recalls the famous example of Jean-Dominique Bobby, who wrote a whole book, winking with one eye ("the diving bell and the butterfly").

In General, according to Mr. Owen, up to 20% of people in a vegetative state actually able to communicate. Of course, there is no guarantee that the new technology will help them return to normal life, but...

Based on the materials of Nature News.