Computational and numerical simulation of the biomechanics of the rat?s vibrissa. Preliminary study of the interaction with surface microstructures

LUCIANNA, FACUNDO ADRIÁN; VRECH, SONIA MARIEL

Congreso; XII Congreso Argentino de Mecanica Computacional; 2018

Vibrissae are specialized hairs located on the snout of several mammals, particularly in rats, commonly involved in tactile sensation. They allow the exploration and recognition of the surroundings through periodical forward and backward movements. The mechanical events evocated by contact are transmitted to the vibrissal follicle located at the whisker base, where they are transduced into electrophysiological signals that go from the afferent neurons to the primary somatosensory cortex. Spatial orientation, object localization and texture discrimination are some of the tasks that rats can do with this sophisticated system. Particularly in the latter case, the rat can discriminate between textures with a difference of 30 μm in roughness. This excellent capacity makes the vibrissal system an interesting subject of study for biological studies, as well as for its possible engineering applications. This work presents a two-dimensional computational model through a Finite Element formulation for the analysis of the mechanical behavior of the vibrissae in contact with surfaces of variable roughness. In order to do this, the study was restricted to the analysis of discrete events in the whisker kinematics resulting from its collision with surface microstructures. We analyzed a possible correspondence between the results obtained in terms of stress, and acceleration with the neural activity from electrophysiological studies in the literature. This work is a preliminary study in the development of a more complex and general numerical model that will allow the study of the correlation between the mechanical behavior with the neural activity of the vibrissal system.