Subject: Re: pitch shift with age From: Peter Cariani <peter(at)epl.meei.harvard.edu> Date: Thu, 24 Sep 1998 11:36:37 +0100Pierre Divenyi wrote: > > The fact that pitch shift occurs also for virtual pitch/missing > fundamental makes the cochlear explanation essentially useless or, at > the least, severely incomplete. An alternative explanation proposed > (sorry, I don't have the reference at this moment -- maybe someone > does?) tied the phenomenon to the well-documented general "slowing > down" of nerve activity with age (Birren, J. E. & Fisher, L. M., > Annual Review Psychology 46 [1995]). > > My own experience with this phenomenon has been pretty dramatic: I > once had AP (less than 1% error) and currently misjudge a pitch by as > much as a whole tone. > > Pierre Divenyi My sense is that relative pitch matches (e.g. of pure tone pitches with those produced by click trains or other complex stimuli such as with missing fundamentals) do not systematically change with age (is this correct?). Absolute pitch on the other hand involves some kind of stored template or representation that must be "read out" to be compared with an incoming stimulus. One possibility would be that internal templates for absolute time duration and absolute pitch are temporal in nature, but in later life are "read out" at a slightly slower rate, so that events appear to occur slightly faster (relative to the internal templates) than they formerly did. Absolute pitch judgements would then shift upward. (Is it always an upward shift of pitch that is associated with age? Never downward? Is there such a thing as absolute rhythm, and is there also an age effect there?) Any temporal storage mechanism that depended on cellular clocks or conduction times would be subject to systematic changes in these cellular processes that could occur with age. Some of these putative mechanisms might be probed by looking at absolute pitch judgements made at different body temperatures, e.g. when someone has a fever. There are many parallels between rhythm and pitch perception, so one wonders whether the same general kinds of mechanisms could be involved, albeit operating over different time regimes. Pierre, it would be most interesting if you or someone else could dredge up that reference. Peter Cariani Email to AUDITORY should now be sent to AUDITORY(at)lists.mcgill.ca LISTSERV commands should be sent to listserv(at)lists.mcgill.ca Information is available on the WEB at http://www.mcgill.ca/cc/listserv