Subject: tonality From: Eckard Blumschein <Eckard.Blumschein(at)E-TECHNIK.UNI-MAGDEBURG.DE> Date: Fri, 14 Jul 2000 19:26:52 +0200Dear Peter, Thank you for your expert and fairly concise reply! What about my theses, I am sure that we both share several common objections against the still dominant concept of spectral energy by J. M=FCller, dating back to 1838. In contrast to Leonhard and also to Josef Manger who's life fulfilled the Chinese saying "one has to swim against the stream in order to reach the spring", I consider myself humbly searching rather than revolutionary. Hoping for getting antitheses, I will send a copy in German to you as well as to everybody else who drops me a line. I am also going to translate and complete my theses, design a home page of mine and put them on it, however, not before late August.=20 No, I am not a moralist, and I do not disdain well done meat except it stems from a mad cow. Al Bregman was perhaps closer to the truth when he called Jont, Andrew and me altruistic individuals. You got me entirely wrong. I just stressed my rather rational creed that everybody is, and more importantly we all together are, first of all obliged to use our mental resources as carefully as possible. Admittedly, I myself am a sinner against the commitment for care, too. So we both might benefit from mutual hints. Let's try to avoid confusion.=20 When I carelessly wrote "late understanding" I expressed my rash pride, having possibly made a step towards better understanding of hearing right now. I am aware that this was not yet comprehensible from my scarce depiction. Be patient. Moreover, according to your denial of lacking stimulus synchronism, I was wrong in my second suspicion. So I have to accept your rejection of the topic of "block-voting" back to what you called cochlear filtering. Well, the pattern is largely plausible from the typical temporal record of a vowel "a", and one could anyway not expect a rapid build-up of resonance modes after each main pulse. Nevertheless, I would be curious to compare the neurograms with spectrograms of the corresponding stimuli. Do you have both data? Hasn't the spectral envelope of an "a" much deeper valleys between the fundamental at about 120 Hz and the first three formants at about 500, 1400, and 2500 Hz then obvious to me from the neurogram? Has anybody checked whether or not the efferent feedback possibly supports the recognition of blocks/formants? My primary concern is still the question how to explain harmony, tonality and the obvious limitation of the latter. In that respect I am partially disappointed by your position.=20 I wonder if merely PSTHs are important. Do population-interval methods include interval histograms, too? Do not the latter better allow to separate refractory effects? You wrote (in 5.): Lower frequency hearing has more autocorrelation-like qualities (...) while high frequency hearing has more modulation-like qualities (intervening clicks mask, [temporal]envelope matters, phase can change envelope shape and modify pitch). I only can guess that you refer to hearing within vs. beyond the upper limit of tonality and phase-locking. Given this holds, I agree that largely ICIs are perceived within the "low-frequency" area. However, modulation transfer below the lower frequency of tonality limit is also important. It starts as soon as period exceeds refractory time, becomes gradually more prominent with rising period and extends far beyond the lower limit of audible frequency. Do you call this perception with infrapitch sized f0 (e.g. 5 Hz) high frequency hearing?=20 What about autocorrelation, I am happy because we both fully agree, application of autocorrelation function on the stimulus is not justified. While my suspicion against adequacy of autocorrelation function largely rests in analysis and generalization of many failed mathematical approaches to basic signal processing in hearing, Christian and Laurent provided a mature entity of compelling evidence against alleged equal perception of lower and higher-order ICIs. I do not understand your objections. Which of their arguments is overdrawn and should not be taken at face value?=20 Are there really still psychophysicists who tacitly associate resolved harmonics with spectral pattern mechanisms? I hope that the time of debating on that topic is over. You are in position to provide overwhelming evidence from the auditory nerve for the neurons to rely on ICIs rather than place. I reminded of compelling functional reasons stated by Roederer. Why do you not definitely exclude any kind of central spectrum maps? You are undoubtedly correct. Hearing is in the end certainly a unitary sensation. Nonetheless, from the level of CN up to the cortex, I would not belittle the fundamental difference between primarily tonotopical coding and diffusely bypassed information.=20 -- Eckard Blumschein