The Brain- A Precious Possession

Tremendous advances recently taking place in neuroscience research have contributed a lot more information than hitherto available about brain functions and brain diseases. Every person has the right to a better understanding of the role of brain in his activities and the biological basis of various disorders, be it infections, drug abuse or mental illness. We must realise that each higher function, besides the biological activities for survival, has a specific region allocated in the brain. Thus we have brain parts for thinking, reasoning, judging, decision-making and imagining. The book is designed to impart the basics of these capabilities and some common ailments of the brain.

Gomathy Gopinath got her degree from the All India Institute of Medical Sciences (AIIMS), New Delhi. She did her postgraduation in anatomy, and is at present Professor and Head of the Department of Anatomy. Her focus of research interest is brain and other studies linked to it. She has travelled widely and continues to enthuse youngsters in the field of neuroscience.

A humble attempt has been made to present an overview of the brain, the most complicated machinery which has not been taken apart completely. Potentials of the human brain are still being discovered and there is a long way to go before even half the capabilities are tapped. We are still groping for complete answers to a number of questions regarding the functioning of the brain. Whatever we know of the brain is in bits and pieces, similar to that of the interpretation of an elephant by four blind men. Despite the bits of information available to the neuroscientists, neurologists and neurosurgeons, a lot has been done to alleviate the sufferings of the human race. Just imagine how much more could be done if more information was available!

I feel it mandatory for each of us to know something about the brain because the brain makes it possible for us to think and feel, remember and reminisce, enjoy and create and thus experience the full richness of life. This is also the decade of the brain, the organ that makes us human, the organ that still poses a supreme challenge to humans.

A structural survey followed by the basic principles of how the brain functions are introduced before dealing with some of the organised functions of the brain. In making the presentation concise and understandable, confusion is created. My writing skill primarily and the vast amount of literature in neuroscience secondarily can be blamed for the confusion. All the same I sincerely hope what is presented conveys sufficient infrastructure to build on further information on the brain if one so desires.

In the words of Hippocrates, the Greek physician : "Some people say that the heart is the organ with which we think and that it feels pain and anxiety. But it is not so. Men ought to know that from brain and from the brain only arise our pleasures, joys, laughter and tears. Through it, in particular, we think, see, hear and distinguish the ugly from the beautiful, the bad from the good, the pleasant from the unpleasant..."

Brain thus is the most precious possession of human beings. It is the organ responsible for the special position the humans enjoy amongst all the creations of nature. Much of what we know about the brain and its functioning has been the result of researches during the last few decades. I am therefore happy that the National Book Trust, in its efforts to keep the lay public informed, decided to request Prof. Gomathi Gopinath, a distinguished neuroscientist, to prepare this monograph. She has produced a very admirable write-up on this complex subject in simple language, supplemented with appropriate illustrations, which make for interesting reading. Starting with a brief description of the various components of the central nervous system she has elaborated on how we perceive sensations and execute voluntary movements. She has then described the organisation of more complex functions like learning and memory. Brief reference has been made on how this knowledge is useful in understanding some of the diseases afflicting the nervous system. I have no doubt that the basic information provided in this book will stimulate a perceptive, though uninitiated, reader to seek for more detailed information about this most wonderful gift of nature.

The brain, one can say is the band-master of the body and mind, controlling the bodily activities and behaviour. Besides bodily activities, other functions like learning, thinking, making decisions, emotions and our social behaviour are also regulated by the brain. It allows us to think, hope, dream and let our imaginations go wild. Recently the brain has been compared to a supercomputer yet to be devised. This is the organ which has set the humans on top of the other species. It is also responsible for conquering the outer space, facing two world wars and the constant strife continuing on earth.

To carry out all the functions, the brain has to be aware of what is happening in and around the organism. For such awareness the brain has to be in contact with all parts of the body and the environment. So the brain has to have parts which serve as information receiving stations, parts which interpret the information, parts which process the information to understadable components for decision making and parts which convey the decisions and carry out the commands. Further it needs to store the experience for future occasions. Thus the brain has different parts.

Only by the seventeenth century did the general outline of the brain become clear through anatomical examination. By nineteenth century it was learnt that the brain or more scientifically termed nervous system was made up of small functional units, called-neural cells or neurons.

Active efforts to understand the brain and its functions have been afoot since long. These efforts have been augmented recently with the declaration of the brain decade in 1990. Yet we are far from achieving the anticipated breakthrough in answering problems such as why we are unable to live happily together on this earth and how to prevent or cure the devastating disorders of the brain. However, the progress in understanding the brain has been promising. This is achieved mainly by the new tools and techniques available to study the structure and functions of the living brain. Currently available are the Computerised Axial Tomography (CAT), Magnetic Resonance Imaging (MRI) and Positron Emission Tomography (PET) scans, which beside showing us the structure of small areas, also tell us the functional status of each region. Another powerful tool, used extensively in all the modern laboratories, is the molecular genetics to probe the genetic basis of developmental disorders like mental retardation, spasticity, etc. As a result of these new tools, detection of even tiny lesions of the brain is easier and early for timely treatment. New drugs for some of the disorders are being discovered. Prosthesis or artificial sensory system to give hope to the persons with damaged sight and hearing is also now available. Discovery of some of the genes responsible for a few of the developmental disorders may lead to gene therapy of such conditions in the near future.

**Contents and Sample Pages**