Subject: Re: Cochlea Amplifier models : a new list From: Martin Braun <nombraun@xxxxxxxx> Date: Wed, 10 Oct 2007 17:39:52 +0200 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>> I haven't been able to find the evidence for the assertion that neural > tuning remains unchanged in some way that differs from the sense in which > BM tuning remains unchanged; [.......] > Where should I look to study the data on this idea that underlies your > modeling approach? You can take any data on level dependence of neural responses. None of them mirrors the half-octave shift of BM tuning. If you have a pure-tone generator, you'll have it even easier. Pull up the sound level from 60 dB to 90 dB. Do you, or don't you, hear the half-octave shift of BM tuning? Martin --------------------------------------------------------------------- Martin Braun Neuroscience of Music S-671 95 Klässbol Sweden web site: http://w1.570.telia.com/~u57011259/index.htm ----- Original Message ----- From: "Richard F. Lyon" <DickLyon@xxxxxxxx> To: <AUDITORY@xxxxxxxx> Sent: Wednesday, October 10, 2007 4:46 PM Subject: Re: Cochlea Amplifier models : a new list > At 2:54 PM +0200 10/10/07, Martin Braun wrote: >>2) At high sound levels: >>Here BM tuning is shifted by about half an octave towards the base of the >>cochlea, whereas neural tuning remains unchanged. > > I haven't been able to find the evidence for the assertion that neural > tuning remains unchanged in some way that differs from the sense in which > BM tuning remains unchanged; in the BM case, the location of the maximum > moves toward the base; it might be hard to assess the location of the peak > of the neural response, since the respond rate is pretty compressed near > the location of maximum, but is there data on that? My impression was > that it does not differ in any significant way from BM tuning; assessing > the tuning by phase response is much easier (e.g., spacing of waveform > peaks and PSTH peaks in response to a click, or waveform autocorr peaks > and revcor peaks in response to a noise). These do change just a bit with > level, in close agreement with TW models that include appropriate > nonlinearities, e.g. as shown in Kiang's original click data of 1965 and > everything subsequently. > > Where should I look to study the data on this idea that underlies your > modeling approach? > > Dick >