on the localisation in the superimposed soundfield - Hauptmikrofon ...

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It is assumed that the relationship between the in- and output signal can describe the
behaviour of this hypothetical processing stage. This functional principle is not meant
to replicate the inner structure of the sensory processing. Its functioning requires the
materialisation of the experience processes in the past, so that the stored binaural
correlation pattern is available.
A characteristic of the location association stage is its selective property. The signal
coming from the peripheral stage (see Section 3.2) contains information about spatial
as well as gestalt features (of one sound source). The spatial information is recognised
with the help of the pattern recognition process, whilst the gestalt information is
discriminated by means of the adaptive filter and then passed on to the gestalt
association stage.
In other words, the impinging signal is ‘freed from’ the influence of the outer ear with
the help of the location-dependent filter “M -1 ”, the weighting of the source signal by
means of the effective transfer function is reversed, and the source signal as well as
the information obtained about the direction and distance of the source are forwarded
separately.
3.2 The association model
The new localisation model is called “association model”. Before depicting the
functioning of the complete localisation model, the fundamental approach – i.e. to
regard localisation as the result of a perceptual process that is solely possible because
of auditory experience – shall be described in a more detail.
3.2.1 Sensational or perceptional model?
In the sensory system, the hypothetical association process corresponds to the function
of a highly effective filter carrying out information reduction in-between peripheral
reception and conscious perception. On the one hand, stored association patterns that
are influenced by previous experience give rise to a meaningful selection of
information. On the other hand, in spite of the information reduction, they allow for a
sufficiently accurate recognition of the stimulus configurations of the environment
(MARKO 1971, KEIDEL 1973).
If, due to lack of experience, missing adaptation or biological reasons, no associations
can be formed, meaningless sensations rather than conscious perceptions will be the
consequence. This phenomenon is well known in the field of neurophysiology.
Deactivation of the so-called association cortices in the sensory system causes
perception disorder, i.e. it impairs the perceptual function of sensory information