Subject: Re: finger nails on blackboard From: David Mountain <dcm(at)ENGC.BU.EDU> Date: Tue, 31 Jul 2001 20:46:26 -0400Several years ago we were working with a type of evoked potential that we called the envelope following response. Most of our work was with sinusoidal carriers and sinusoidal envelopes but we experimented a bit with pseudo-random envelopes and these stimuli were among the most unpleasant ones we've ever listened to. We ran the stimuli through a simple auditory nerve model and saw instantaneous firing rates that were much higher than what one normally sees with continuous stimuli. It appeared that brief segements of low amplitude followed by an amplitude peak was creating a situation where the model nerve fiber could partially recover from adaptation and thus be able to respond vigorously to the following peak. -------------------------------------------------------------------- David C. Mountain, Ph.D. Professor of Biomedical Engineering Boston University 44 Cummington St. Boston, MA 02215 Email: dcm(at)bu.edu Website: http://earlab.bu.edu/dcm/ Phone: (617) 353-4343 FAX: (617) 353-6766 Office: ERB 413