Biomusicology: Neurophysiological, Neuropsychological, and Evolutionary Perspectives on the Origins and Purposes of Music

If one analyses the specific trigger feature of cortical cells with intracellular recording methods, it becomes obvious that inhibition plays a major role in the specification of these features. . . .

The cortical network thus can be considered as a nonlinear spatiotemporal filter that allows through only aspects of the signals transmitted to it through its thalamocortical afferents. This should be the case independently from the actual origin of the thalamocortical signals, i.e., whether they come from specific, somatotopically ordered relays or from intrinsic projection nuclei, which may already contain, in their internal topography, a highly complicated spatiotemporal transform of the environment"⁸⁵

From this interpretation one may conclude that the auditory primary cortex has an integrative function, in our agreed upon sense of the term. It is unnecessary for tonal discrimination per se (pure-tone audiogram, ITD and IID) which depends on a space- temporal encoding in subcortical centers, but is essential to the process of maintaining neural temporal responses, elicited subcortically, long enough to be integrated into a complex sensory description of the stimulus. Like the visual cortex, the auditory cortex, in its fun extension, does perform a feature analysis of its stimuli, though its organization appears to be less tight. Examined and evaluated in relation to the nature and composition of the acoustic stimuli and their functional role in an action-oriented, well-adapted behavior, the analysis is probably as efficient as that performed by the visual cortex.⁸⁶

What are the main functional aspects of an action-oriented auditory behavior?

With the exception of the behaviorally significant audiomotor reflexes (e. g., the auditory-evoked startle response, which we will discuss in our next chapter), we have learned of all the others: the

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