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Re: Is there considerable phase locking up to 6 kHz?

Dear all,

I appreciate clear objections against the idea of periodicity detection
from temporal envelope by Roy Patterson: "The work on IRN stimuli suggests
that periodicities are not a necessary and sufficient condition for
processing complex pitch, since there are no periodicities in the IRN
waveform (see Yost et al, 1996), yet they have a clear pitch (see Yost,
1996a). Our current work suggests that the information for processing the
pitch of IRN stimuli is not in the envelope."

However, we all should be wary of thoughtlessly using notions like spectrum
and temporal fine structure.
Already the fundamentally inappropriate traditional spectrogram illustrates
that the iteration of a segment of noise without any spectral profile
introduces an audible spectral signature. Of course, the FCT-based natural
spectrogram shows a more realistic picture of firing pattern in the
auditory nerve. I remind those who do not trust in FCT, because they
wrongly put it in the drawer of an exotic mathematical idea while it
actually replaces FT, of the need to define what we are talking about if we
are using terms like spectral component.

Martin Braun is certainly correct in that, there are at least two main
streams of auditory information within each CN. However, he apparently
ignores tonotopy as long as he doesn't follow my suggestion that place code
is the best base for subsequent temporal processing. For more than a
century, Fourier analysis and place code were considered the basis of
hearing and of related audio technology because alternative temporal models

Why not seriously dealing with an unseen mathematically correct and
physiologically plausible model that unites function of cochlea and brain
in a somewhat strange hidden manner which is already known as cepstral
analysis? It also may elucidate why different codes contribute to a unitary

I do not appreciate glossing over FCT as a red herring since such emotional
arguments are difficult to falsify. Nonetheless, I would hope that expert
listeners confirm or deny the putative 400/800 Hz confusion. So far, I am
only aware of a plausible 50/100 Hz confusion in case of iterated noise
segments with alternating polarity inversion (Warren & Wrightson 1981).

Eckard Blumschein