Subject: Re: Cochlea Amplifier models : a new list From: Erik Larsen <elarsen@xxxxxxxx> Date: Wed, 10 Oct 2007 09:44:15 -0400 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>What would be the point of protecting the region tuned to the frequency at which high levels of energy are present, at the expense of the region tuned to half an octave higher? As I'm sure you know there is a long list of publications showing this pattern of acoustic injury. Perhaps the shift in best frequency is an epiphenomenon? Erik > 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. The effect of > this shift is that BM vibrations absorb acoustical energy, before it > reaches the OHCs that are tuned to the same sound frequencies. Thus it > is evident that this mechanisms must contribute to the protection of > OHCs from overstimulation. > > http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=ShowDetailView&TermToSearch=7961182&ordinalpos=6&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum > > > > In summary, at low sound levels BM vibrations are an epiphenomenon of > OHC motility, and at high sound levels they are specifically tuned to > absorb energy for overload protection. -- Erik Larsen PhD candidate Speech and Hearing Bioscience and Technology http://web.mit.edu/shbt You will stop at nothing to reach your objective, but only because your brakes are defective.