Subject: Re: The climb of absolute pitch From: Bob Masta <audio@xxxxxxxx> Date: Tue, 4 Dec 2012 08:32:42 -0500 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>Martin: Thank you for your comments. You mention that: "The pitch shift that has been discussed in this threads has nothing to do with any of this. It has been proposed that its cause lies in the biochemical alteration of the speed of the intracellular neural reference oscillators in the pitch extracting areas in the central nuclei of the inferior colliculi." Reference oscillators? Are these for real, or just part of the proposed pitch shift explanation? I guess I have a hard time envisioning a biological oscillator with the required accuracy and stability, but on the other hand AP would seem to require *something* with accuracy and stability... I guess I was just assuming it was the BM mechanics. Best regards, Bob Masta ============================== On 3 Dec 2012 at 12:51, Martin Braun wrote: > Dear Bob and others, > > > Can someone explain the supposed mechanism behind neural > > timing and pitch shift? > > There is no evidence for such a mechanism. > > > > As I undestand it, since pitch is encoded as > > *place* along the BM, > > "*place* along the BM" "encodes" spectral content of the sound, not pitch. > The coding for pitch is synthesized from these signals in the auditory > midbrain. > > > > The firing rate does not encode the frequency of > > the sound itself. > > Up to certain frequency values it does encode both the frequency of spectral > components and the frequency of the fundamental of harmonic complex sound. > > The pitch shift that has been discussed in this threads has nothing to do > with any of this. It has been proposed that its cause lies in the > biochemical alteration of the speed of the intracellular neural reference > oscillators in the pitch extracting areas in the central nuclei of the > inferior colliculi. > > Martin > > ------------------------------------------- > Martin Braun > Neuroscience of Music > S-66492 Värmskog > Sweden > email: nombraun@xxxxxxxx > web site: http://www.neuroscience-of-music.se/index.htm > > > > > > ----- Original Message ----- > From: "Bob Masta" <audio@xxxxxxxx> > To: <AUDITORY@xxxxxxxx> > Sent: Sunday, December 02, 2012 2:47 PM > Subject: Re: The climb of absolute pitch > > > > Can someone explain the supposed mechanism behind neural > > timing and pitch shift? I don't understand what is being > > proposed. As I undestand it, since pitch is encoded as > > *place* along the BM, the neurons respond with a firing > > rate that encodes *loudness* for their particular frequency > > place. The firing rate does not encode the frequency of > > the sound itself. > > > > What am I missing here? > > > > Best regards, > > > > Bob Masta Bob Masta D A Q A R T A Data AcQuisition And Real-Time Analysis www.daqarta.com Scope, Spectrum, Spectrogram, Signal Generator Science with your sound card!