Subject: Re: Bite-induced pitch shift? From: Brad Ingrao <info(at)bradingrao.com> Date: Thu, 19 Jun 2003 16:16:44 -0400Robert Levine at the Massachusetts Eye and Ear Infirmary has noticed that some of his patients can change, cease or initiate tinnitus with jaw or neck movements. One theory on this may be that the Dorsal Cochlear Nucleus is getting stimulated and is somehow communicating with the Olivo-Cochlear Bundle and sending (or inteurrupting) effernet signals to the cochlea via the outer hair cells. If the theory holds that part of our ability to hone in on frequency estimation, and therefore pitch, is related to this Olivo-Cochlear feedback loop, then pitch shifts with massiter muscle contraction doesn't seem that far fetched. ____________________________________________ Best Regards, Brad Ingrao, M.S.Ed. CCC-A, FAAA Editor EDEN - The Electronic Deaf Education Network www.bradingrao.com e-mail: info(at)bradingrao.com -----Original Message----- From: AUDITORY Research in Auditory Perception [mailto:AUDITORY(at)LISTS.MCGILL.CA] On Behalf Of Bob Masta Sent: Thursday, June 19, 2003 3:45 PM To: AUDITORY(at)LISTS.MCGILL.CA Subject: Bite-induced pitch shift? Dear List: In the June 9 issue of Electronic Design <www.elecdesign.com> analog electronics guru Bob Pease mentions that when he bites down hard "on some tough nuts or a popcorn cake, the pitch seems to dip momentarily by about half a note". Has anyone heard of a phenomenon like this? (The effect doesn't seem to work for me, at least not when biting down on a plastic toothbrush handle.) He wonders what can cause this. If this is truly a pitch shift and not a resonance envelope (formant) shift due to distorting the ear canal, could it be deforming the cochlea such that the stiffness of the basilar membrane is changed? Seems pretty extreme! Any ideas? Robert Masta tech(at)daqarta.com D A Q A R T A Data AcQuisition And Real-Time Analysis Shareware from Interstellar Research www.daqarta.com