Neuroscience
research has come to a paradoxical stage. During the past century and a half,
we have learned a great deal about the elementary processes that govern the
functioning of individual neurons and glial cells and of the junctions that connect
them. Yet, we must admit that we have no solid theory, not even a conceptual framework,
of the workings of the system as a whole. The paradox lies in the fact that, in
spite of our bafflement and frustrating inability to understand its normal
operation, we have gained considerable insight into the ways in which cerebral
function can go wrong. This, the mechanisms of some of the most severe afflictions
that can befall the brain, is a main topic of this volume. In this matter, the
pathophysiology of the brain, we might say that a major chapter has just been
completed, at least in outline, while the next one is just beginning to be
written. We have a good understanding of the way in which cells and groups of
cells behave when seized by epileptic fits and of what happens, on a microscopic scale, when brain cells are
deprived of oxygen. We have been able to observe the tides of ions flowing into
and out of cells, and we have learned how ion fluxes feed back on the ion
channels through which they pass. This is the part that is more or less
complete, save some missing details, and it is the main topic of this book. The
next chapter, dealing with molecular and submolecular processes, which is still
in an incipient stage, is touched on but not reviewed in detail.
The emphasis in
the book is on advances made in the past few decades, without neglecting the
road by which we have arrived at the present stage of knowledge. A true historical
survey cannot be accommodated in this small volume, but each major topic is
introduced by highlighting the historical background, casting a backward glance
at the origins and the evolution of current ideas. Each chapter concludes with
a selection of the major theses developed on the preceding pages. As the
reference section attests, the literature is enormous.
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