Why should there be a handbook of sensory physiology, and if so, why
now' The editors have asked this question, marshalled all of the
arguments that seemed to speak against their project, and then
discovered that most of these arguments really spoke in favor of it:
there seemed to be no doubt that the attempt should be made and that it
should be made now. No complete overview of sensory physiology has been
attempted since Bethe's "Handbuch der normalen und pathologischen
Physiologie", nearly forty years ago. Since then, the field has evolved
with unforeseen rapidity. Although electric probing of single peripheral
nerve fibers was begun by ADRIAN and ZOTTERMAN as early as 1926, in the
somatosensory system, and extended to single optic nerve fibers by
HARTLINE in 1932, the real upsurge of such single-unit studies has only
come during the last two decades. Single-cell electrophysiology has now
been applied to all sensory modalities and on almost every conceivable
phylogenetic level. It has begun to clarify peripheral receptor action
and is adding to our. understanding of the central processing of sensory
information. In parallel with these developments, there have been
fundamental studies of the physics and chemistry of the receptors
themselves: these studies are leading to insights into the mechanisms of
energy transduction and nerve impulse initiation.