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The 1906 Nobel Prize for medicine and physiology honored
what can be thought of as the beginning of mod?ern neuroscience. The prize went
to Camillo Golgi and Santiago Ramon y Cajal. Like many advances in science,
Golgi's serendipitous discovery of a remarkable technique to observe cells in
brain tissue allowed both men to make seminal contributions to the
understanding of the nervous system. The Golgi staining technique, as it has
come to be known, employs the immersion of brain tissue in chromate and silver
solutions, which results in the deposition of silver salts in small numbers of
nerve cells. Through the microscope, the silver impregnation reveals the
complex features of neural cells in stunning detail. Since only small numbers
of neurons in a piece of tissue are impregnated by the silver deposits, It was
possible for the first time to see a single cell with its many processes in
isolation from its neighbors.
For turn-of-the-century scientists, the new technique would
lead to a fundamental change in how the brain was conceptualized. It became
abundantly clear that the brain was composed of diverse cellular elements. Like
many advances in science, this one was not without debate. Golgi held the view
that the vast numbers of nerve cells with their many branching processes were
an unbroken chain of physically interconnected cells that formed a grand
network. Cajal, on the other hand, was convinced that the nerve cells were
discrete entities separated from each other. Cajal was correct in presaging the
existence of synapses between nerve cells, but proof would have to await the
invention of the electron microscope. Nevertheless, for many students of
neuroscience, Cajal's observations and explanations of the organization,
development, and function of the nervous system were prophetical.
It is now 90 years later, we are in the middle of the last
decade of the twentieth century, the Decade of the Brain, and 1996 is the
fiftieth anniversary of the National Institute of Mental Health. As we close
out this century and enter the twenty-first, research of the brain will be
devoted to answering a most complex question: How do the cells of the nervous
system produce behavior and cognition, store memory, and execute other complex
phenomena?
The brain, and in particular, the human brain, has been
called the last frontier of biomedical sciences because of its enormous
complexity. The average brain cell is both like and unlike every other cell of
the body. The little bag of tricks the liver cell uses for daily housekeeping
is similar to that of the nerve cell. However, nerve cells have evolved these
tricks for their own specialized functions.
Unlike the liver, which is composed of a relatively
homogenous population of cells, the brain has a multitude of diversity. The
organization of this second edition of "The Neuroscience of Mental Health"
reflects this diversity. The nine chapters comprising this volume address the
following areas:
- Neural Development
- Functional Organization of the Central Nervous System
- Neurotransmission
- Neural Regulation of Behavior
- Cognitive Neuroscience and Neural Plasticity
- Neuropsychopharmacology
- Neuroimmunology and Neurovirology
- Advanced Technologies for Neuroscience
- Neural Basis of Psychopathology
These chapters are offered to both the casual reader and the
serious student of modern neurobiology as an attempt to capture the state of
the art in each of these areas of research. A paradox of sorts will become
apparent in the scientific content of each chapter. This paradox is rooted in
the tremendous diversity across each of the subdisciplines, yet each chapter is
linked to the others by a fundamental commonality. Indeed, discoveries in one
area of neuroscience rapidly find applications and open new areas of
understanding across widely divergent scientific and clinical investigations.
For example, the concept of plasticity first encountered in chapter 1 in the
presentation of neural development is a recurring theme throughout this
treatise.
Plasticity, or the ability to change, is one of the
underlying principles of the nervous system - it is not only a phenomenon of
the embryonic brain, it is a dynamic process operating at all levels of
organization throughout the life of the organism. Rooted in the mechanisms of
plasticity are molecular elements that also happen to be the fundamental
elements of neurotransmission - a discussion of one cannot take place without a
discussion of the other. Likewise, any conversation on how drugs affect the
brain and behavior (neuropsychopharmacology) requires the language of
neurotransmission, because many drugs work by affecting neurotransmission.
Perhaps the most exciting, and as yet least understood, example of plasticity
in the brain is learning.
The diversity and the commonality linking seemingly
disparate fields is the basis of one important insight into the future
direction of neuroscience research. When the first edition of this book was
published 10 years ago, it was possible for researchers to identify themselves
along scientific disciplinary lines. For example, one might be a psychologist,
an anatomist, a molecular biologist, a psychiatrist, a biochemist, or a
pharmacologist. Now and into the future, investigators of the brain must be
integrative across once-distinct disciplines. The nature of the questions
demands multidisciplinary answers.
One only needs to read the chapter on neuroirnmunology and
neurovirology to see the complex integration between brain function, mental
state, and the physical state of the body. We can no longer conceptualize the
brain in isolation from other organs and organ systems. Of even greater
importance is the need to Integrate the biology of the brain with some of its
major functions, behavior and cognitive function.
A reading of this book will provide an overview of the kind
of basic and applied research that has advanced our understanding and treatment
of mental disorders. Indeed, progress in basic neuroscience research is of
benefit to a wide variety of human disorders from mental illness to
neurological problems. It is particularly gratifying to see how the past 50
years of NIMH support for basic neuroscience has resulted in pivotal
contributions to our understanding and treatment of many of the mental
disorders. Numerous specific examples can be cited, but perhaps the most
profound observation lies in the fact that our advances in basic neuroscience
have profoundly changed how we think about mental disorders. Both the
specialist and nonspecialist now appreciate the biological basis for diseases
of the mind. As new insight is brought to bear on the relationship between the
workings of nerve cells, behavior, and the environment, progress in the next 10
years will doubtless be even greater.
*This article was
originally published in The Neuroscience of Mental Health, NIMH
Publication No. 95-4000, 1995, pp. 1-3.
[National Institute of Mental Health
copyright status]
The NIMH material reprinted here is in the public domain
and NIMH allows it to be used or reproduced without permission from the
Institute. "Citation of the source is appreciated".
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