Stretch Receptors in the Mammalian Tympanic Membrane. (Biological Science Section).

Fletcher, T.C. and M.G. Scott. Division of Agriculture, Natural Sciences and Mathematics, Lincoln University. STRETCH RECEPTORS IN THE MAMMALIAN TYMPANIC MEMBRANE. Stretch receptors in the tympanic membrane are potential air pressure detection systems in mammals. Human ears with damaged tympanic membranes are less sensitive to air pressure changes than healthy ears. The pars flaccida may be the region of the tympanic membrane that is responsible for pressure detection in humans. It seems to minimize static air pressure differences between the ear canal and middle ear cavity by the passive movement of the membrane toward the side of lower air pressure. Encapsulated nerve corpuscles that are embedded in the pars flaccida may function as mechanoreceptors that sense the pressure difference. The objective of our current research is to extend these observations from humans to other mammalian species. We are currently examining the tympanic membrane of two bat species to determine whether they have similar sensory receptors. The bat species studied include Pipistrellus subflavus and Eptesicus fuscus. Supported by the Heartland Alliance for Minority Participation.