By RAS Corresponding Member, SvyatoslavMEDVEDEV, Director of the RAS Institute of the Human Brain

The human brain, the principles and mechanisms of its functioning, its links with our psyche, intellect and soul... Lying in store for scientists engaged in this line of research are many puzzles and unexpected discoveries. This is because the object of research is far more complicated than anything science has tried to unravel ever before: the galaxy, living organism, cell, molecule and the atom. Theory of knowledge- gnosiology-which investigates the essence of man's cognitive attitude to the surrounding world, its "starting points" and universal foundations, asserts that the central tool of our cognition are not instruments and methods, but the brain. But can our brain cognize itself?

During the scientific and technical revolution, in the 1970s-1980s, the world received new methodological approaches and instruments of research which paved the way to serious breakthroughs in studies of the brain. Those years in neurophysiology saw the advent of new methods of cognition of the "inner world" of the nerve cell like magnetoencephalography, functional magneto-resonance tomography, positron- emission tomography, etc.

At the end of last century problems of brain activity were in the focus of attention of specialists in many countries. It was the 1990s which the US Congress proclaimed a decade of studies of the human brain. This American initiative quickly reached an international scale. Actively participating in this research have been our Russian scientists.

The 1990s in this country saw the establishment of the Institute of the Human Brain of the Russian Medical Academy. It was set up on the basis of a department of the Scientific-Research Institute of Experimental Medicine (of the Medical Academy) headed by Academician N. Bekhtereva. Today this is the leading medical center of Russia engaged in studies of the human brain, above all its psychic functions and intellectual activities-of all the things which, practically speaking, make a man a man.

The most important trend of fundamental research of our Institute are studies of the higher brain functions: attention, memory, thinking, speech, emotions, creativity. Dealing with these problems have been several research teams, including our own laboratories

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Diagram of human brain mapping during therapeutic-diagnostic application of implanted electrodes (left) and with the help of positron-emission tomography (right).

headed by myself, Dr. Yu. Kropotov (Biol), and Academician N. Bekhtereva.

Functions of the brain, exclusively human, or most vividly manifested in man, are investigated by various methods. These include using the "conventional" EEG (electroencephalogram) but, naturally, at a new level of brain mapping (establishment of functional specialization of different zones), registration of the pulse activity of neurons and the processes generated by them during curative-diagnostic implantations into the brain of electrodes, the use of positron-emission tomography, etc.

Our Institute is different in principle from most similar centers in the world which traditionally focus on animal experiments. The way we see it, results of experiments with rats and rabbits can fail to produce an exhaustive picture of the work of the homo sapiens brain. And what is more, there are certain phenomena which can and should be investigated on man alone. To give just one example, our laboratory of positron-emission tomography (PET) is investigating brain organization in speech processing, Volunteers are invited who are submitted to tests with the help of what we call non-invasive techniques (such as positron-emission tomographs), which make it possible to study brain activities without surgical interventions.

And there are also cases when an ailment, or accident, "stage" experiments of their own on the brain of a patient. While attending to such patients we are not simply conducting the necessary studies which offer us a unique insight into the mechanisms of functioning of the brain. Having a clinic of our own at our Institute we are able to render to our patients the most timely and highly professional medical care and assistance. In addition to what we call standard medical manipulations on the brain, our experts perform surgical treatment of epilepsy and parkinsonism, psychosurgical operations, including the healing from drug obsession caused by heroin, implantations of fetal (embryonal) brain tissue, treatment by magnetostimulation and many other methods.

Over the years our institute researchers received some very interesting results. For example, they discovered and studied an "error detector" functioning in the brain. And let me

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explain what that means. Say, you shut the door of your house, or apartment behind you, and get a feeling that something is wrong. You step back into your house and discover that you had left the light on in the bathroom. In other words, while performing a daily chain of repeated actions, you missed one of them, and a control mechanism-error detector in the brain-immediately goes into action. It was first discovered by Professor N. Bekhtereva and her staff in the mid-1960s. And in the late 1980s and early 1990s we discovered and studied with the help of this mechanism the phenomenon of error detection not only in deep brain structures, but also the cortex. And quite recently this "error detector" has been "rediscovered" in the \\fest by persons familiar with the studies of our specialists and these people think nothing of plainly "borrowing" these results. They even called it exactly the same way as did Professor Bekhtereva. Today, from the position of the error detection system, it is possible to explain, among other things, the retention of drug addiction.

Prolonged studies of the mechanism of speech formation has made it possible for our Institute researchers to draw up a "map" of sections of the brain which are responsible for syntax, orthography, semantics, etc. This was done by offering our volunteers texts of different degrees of complexity in the reading of which one has to use rules of grammar, logical thinking, etc.; parallel with that, and using PET methods, we measured what we call the activation of different groups of brain nerve cells in the given span of time. By comparing the obtained PET images, it was possible to identify areas of the brain which process separate words of the text, its semantics, syntax, etc.

And one more important and interesting area of research-studies of brain functioning in the process of creative activities, that is when in our mind there takes place not some mechanical, or "pre-programmed" data processing, but something new is produced- images, thoughts, feelings, emotions... Today it is too early to speak about the final results, but one can say with confidence that it has been possible to discover what we call the correlates of creative activity both-at the level of the bioelectric activity of the brain (using EEGs) and in the cerebral blood flow (by PET methods).

We have been actively involved with the problem of adaptation of conscience to all kinds of situations. Our plans for the near future in this field call in particular for investigation of different altered states of conscience, which make it possible for an individual to prepare or adapt himself for the most effective performance of the required activities, and for the identification of their brain correlates. From the point of view of psychology this problem is being dealt with by many scientists, and as for our own institute, we are investigating its physiological "foundations".

We have obtained some unexpectantly interesting results in studying cerebral mechanisms of perception of movements and different kinds of somatosensoric stimulation. In this case the responses of different areas of the brain, as compared with thinking process, are much more authentic and more vividly expressed. This has made it possible, with the help of PET, to identify the functional role of the active zones, separate the processing of sensory information and its perception.

And it is also possible, by using various methods, to "look" into the activities of the brain when a person is performing various kinds of work, and also study different "types" of attention. In recent time these studies have been actively pursued by the laboratory of Dr. Yu. Kropotov, including, in particular, aspects of the problem associated with clinical practice of treatment of disorders like deficit of attention (concentration), or minimal cerebral dysfunction. A short while ago we conducted the presentation of our new center for the treatment of this pathology. Its specialists will develop and perfect the appropriate technologies which will later be passed on to medical practitioners.

This must be the neurosurgery of the future-stereotaxis. And that does not mean that in future all operations will be performed by the introduction of electrodes into the strictly defined sections of inner cerebral structures, although their share will increase manifold. The way I see it, one of the most important achievements in this area has been the elaboration of a comprehensive methodology which incorporates the stereotaxis apparatus of its own and a set of manipulators, and also, what is the most important- stereotaxic neurology. The problem is not only how to "hit the target" and what to do with it, but how to be able to choose this or that "target" in various ailment. It is this awareness that has been behind the positive decision of the Council on Narcology of the RF Ministry of Health which gave us a permission to perform operations on drug addicts. Encouraging results on their treatment have been achieved. And we keep on working on new (and effective) methods of therapy of this disorder. And these methods are so novel, they are not always accepted there and then by the conservative (in the good sense of the word) medical community.

And now a few words about one more of our labs-of neuroimmunology. Its specialists are studying immunological responses to various lesions of the brain and to multiple sclerosis. During observations of victims of this ailment specialists detected a connection between the degree of cognitive disturbances and changes in the metabolism of glucose in the cerebral cortex. This makes it possible to assume that in this case dementia is not only of a subcortical nature, as many authors point out, but is associated with the lesions of the cerebral cortex as such.

And summing it up, one can say that our Institute is a young and promising center which is engaged in a broad range of basic and applied studies and doing a lot of practical work on the diagnostics and cure of brain disorders.

Illustrations provided by the author.

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