9404517 Bell The investigator and his colleagues undertake research to establish a quantitative understanding of mechanotransduction in the mammalian tactile system through modeling a skin receptor (Pacinian corpuscle_PC) and the skin. They develop the mathematical approach for determining the transmission of strain through the PC's capsule, its mechanical filter, and develop strain-sensitive ionic channel models for the PC's nerve fiber. They extend previous work to allow full three-dimensional deformation of the PC and to include inner capsule structure. This will help further understand sources of distinctive neural tuning and directional sensitivity characteristic of the PC. The investigators also develop a continuum skin model to understand the filtering contributions made by the skin. This includes incorporating the biphasic (fluid-solid) character of the skin. Cooperation from an experimental group complements the theoretical efforts. The investigators study, through theoretical models (but in cooperation with an experimental group), how mechanical stimuli at the skin surface are transformed through skin and by a skin receptor into electrical signals. This mechanical-to-electrical process (mechanotrans- duction) gives output that is processed in the central nervous system and ultimately as associated with our perception of touch. Mechanotransduction in general is a fundamental physiological process that is central to such diverse functions as hearing, digestion, balance, as well as touch. Through quantitative modeling of skin receptors (specifically, Pacinian corpuscles) they developin an understanding of the contribution of the mechanical vs the neural part of these receptors (which is presently very difficult to accomplish experimentally); hence, they are able to interpret changes due to aging and abnormalities. The approach they take to modeling the skin as a biphasic (fluid-solid) material is expected to be valuable in studying t he mechanics of other biphasic materials not necessarily associated with biological tissues.
