Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.04.20.050757v1?rss=1 Authors: Luo, Y., Bresee, C. S., Rudnicki, J. W., Hartmann, M. J. Z. Abstract: Nearly all mammals have a vibrissal system specialized for tactile sensation, composed of whiskers growing from sensor-rich follicles in the skin. Because a whisker has no sensors along its length, an open question is how mechanoreceptors in the follicle transduce sensory signals. These mechanoreceptors are activated by whisker deflection, so it is essential to understand how the whisker deforms within the follicle and so how it may activate different populations of mechanoreceptors in different ways. During active whisking behaviors, muscle contractions and increases in blood pressure in the ring sinus will likely affect the whisker deformation profile. Directly recording from mechanoreceptors under these conditions is difficult due to their small size, location within intricate and delicate membranes, and movement during sensation. Using data from a previous experimental study on whisker deflection, and from histological analysis of follicle tissue, we develop a mechanical model of the follicle sinus complex. With this model we first simulate passive whisker contact, replicating previous results of ex vivo experiments on deformation of a whisker within the follicle. We then simulate whisker deformation within the follicle during active whisking. Results of these simulations predict that both intrinsic muscle contraction and elevated hydrostatic pressure within the ring sinus may be regulatory mechanisms to enhance tactile sensitivity during active whisking. The mechanical model presented in this study is an important first step in simulating mechanical interactions within whisker follicles, and aids in the development of artificial robotic follicles. Copy rights belong to original authors. Visit the link for more info