Subject: Re: Perception as memory From: Martin Braun <nombraun@xxxxxxxx> Date: Mon, 31 Aug 2009 22:08:47 +0200 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>Dear fans of AP shift, absolute pitch (AP) does not only shift with age and physiological cycles. It also shifts under the influence of medical drugs, such as carbamazepine and trimipramine. The effect of such drugs on the time constants of membrane dynamics of neurons is extensively documented in the literature. From this we can conclude that the pitch effects are due to interference with the central auditory periodicity analysis that is underlying the perception of pitch. The idea that the basilar membrane (BM) in the cochlea might be involved in AP shift is disproved by the fact that pitch perception is based on central auditory periodicity analysis. The parameters of the BM simply have no influence on the periodicity information that the inner ear sends to the brain. Chaloupka, V., Mitchell, S., Muirhead, R., 1994. Observation of a reversible, medication-induced change in pitch perception. J. Acoust. Soc. Am. 96, 145-149. Koerner, C., Deuschle, M., 2003. Reversible pitch perception shift caused by trimipramine (Congress Abstract). Pharmacopsychiatry 36, 241. Braun, M., Chaloupka, V., 2005. Carbamazepine induced pitch shift and octave space representation. Hear. Res. 210, 85-92. Martin --------------------------------------------------------------------- Martin Braun Neuroscience of Music S-671 95 Klässbol Sweden web site: http://w1.570.telia.com/~u57011259/index.htm