CNS Seminar

Monday February 27, 2017 4:00 PM

The structure of the mechano-tactile input to the rat vibrissal system

Speaker: Mitra J.Z. Hartmann , Department of Biomedical Engineering and Mechanical Engineering , Northwestern University
Location: Beckman Behavioral Biology B180

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Rats are expert at navigating the world in the dark using their sense of touch. They rhythmically brush and tap about 60 large vibrissae (whiskers) against objects to determine size, shape, orientation, and texture. At the same time, whiskers also help the animal sense the direction of airflow, likely helping to localize odor sources. A whisker has no sensors along its length; instead, all mechanosensory information is transmitted to sensors located within a follicle at its base. Now imagine that we could quantify the head movements of the rat, as well as the mechanical signals at the base of every whisker as the rat explores its world through touch and airflow. We would then have access to all of the primary mechanical information that the nervous system requires in order for the animal to perceive its environment through vibrissal-touch. In this talk, I will describe how our lab combines mechanical simulations and experiments, hardware models, behavioral studies, and neurophysiology to study the sense of touch in the rat vibrissal system. We aim to integrate realistic simulations of vibrissal dynamics with behaviorally-measured head and vibrissal kinematics to model the rat's tactile sampling strategies for different objects and airflow. Our goal is to quantify the mechanics at each vibrissa base for a given exploratory sequence and the associated responses of primary sensory neurons in the brain. Ultimately, these data can then be used to constrain computations at more central levels of the nervous system.

Series: Computation and Neural Systems Seminar
Contact:
Department of Computing + Mathematical Sciences