whose intervals are integral multiples of a particular value, and the improvement of the signal-to-noise ratio
of sub- threshold stimuli   It also excludes explicitly supra-threshold stimuli (e.g.,  . From a
biological viewpoint (i.e., physiological, psycho-physical, etc.) signal-to-noise ratio improvement is interesting
always, both when revealing sub-liminal stimuli and regardless of the afferent discharges pattern (e.g. see Figures 1-II, 2-b, 8-c), and when making the no less significant supra-threshold ones more recognizable. Therefore, the biological domain within which stochastic resonance can be applied does not cover entirely
that where living receptors perform; furthermore, the excluded portion includes important situations. These
two features impose bounds on the biological value of stochastic resonance. A theory that covered the entire
range of sub- and supra-threshold stimuli that pervade everyday life would have a broader, more meaningful
domain of applicability, and be more valuable for physiologists. Even better yet in physiological terms would
be theories that, in addition to fidelity improvement in the entire range, explained other noise-induced
consequences (see above). So that this is not misinterpreted, we add our agreement with those who believe
stochastic resonance to be an important theoretical construct with many significant applications in the
practical sciences already, and more are to come.Clearly, the role of noise in neural coding is a multi- disciplinary subject; it has attracted, and profited
by, the joint contribution of several experimental and formal approaches. A balanced perspective, useful
for any scientific endeavor, is particularly desirable (though it may be harder to achieve) when, as here,
viewpoints are multiple and reflect disparate backgrounds. Needed, obviously, is a first evaluation based on
the entire picture and all disciplines. This overall evaluation, though very necessary, is not sufficient. Just as
important is one enunciated after extraction of the chapter from the multi-disciplinary context, and voiced
in strictly biological terms. Indeed, when attempting a balanced perspective of noise and neural coding,
evaluations based on strictly biological criteria are indispensable ingredients. Biologically, then, this research
endeavor, finding a rationale in the natural history of everyday life, generating over decades a coherent set of
experimental observations, and drawing sensible biological conclusions, has demonstrated a life of its own and
delineated a clearcut identity. Judged as such, detached from other viewpoints and independent of otherwise
significant considerations, noise and neuronal processing stands by itself as a self contained, genuine and
significant chapter in the Physiology of the Nervous System. It goes without saying that parallel theoretical
developments provided indispensable conceptual frameworks for understanding formal issues, for planning
further experimental approaches, and so forth.
AcknowledgmentsThis work was supported by Trent H. Wells jr. Inc.
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Questia, a part of Gale, Cengage Learning. www.questia.com
Book title: Origins:Brain and Self Organization.
Contributors: Karl Pribram - Editor.
Publisher: Lawrence Erlbaum Associates.
Place of publication: Hillsdale, NJ.
Publication year: 1994.
Page number: 327.
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