What can we learn about the sense of touch by studying rat whiskers?

 Mitra Hartmann photo

Wednesdays@NICO Seminar, Noon, February 27 2013, Chambers Hall, Lower Level

Prof. Mitra Hartmann, Northwestern University

Abstract

Rats rhythmically brush and tap their large mystacial vibrissae (whiskers) against objects to tactually explore their surroundings. Using mechanical signals from its vibrissae, a rat can determine an object’s size, shape, orientation, and texture. Our laboratory uses the rat vibrissal system as a model to understand how sensory and motor signals are integrated during tactile exploratory behavior. In this talk I will describe our laboratory’s recent advances in quantifying the complete mechanosensory input to the rat vibrissal array during natural exploratory behaviors and discuss implications of these results for neural processing. I will specifically focus on our laboratory’s efforts to develop a simulation environment that permits full dynamical simulations of vibrissal-object contact. We aim to integrate realistic vibrissal dynamics with behaviorally-measured head and vibrissal kinematics to model the rat's sampling strategies for various objects in the environment.  Ultimately, the simulation system will be used to predict  the mechanics at each vibrissa base for a given exploratory sequence, and thus predict the input to the brain. 

Supported by NSF awards IOS-0818414, IOS-08090000, and EFRI-0938007.

Biography

Prof. Mitra Hartmann received a Bachelor of Science in Applied and Engineering Physics from Cornell University, and a PhD in Integrative Neuroscience from the California Institute of Technology. She was a postdoctoral scholar at the Jet Propulsion Laboratory in Pasadena, California in the Bio-Inspired Technology and Systems group, and joined the faculty at Northwestern University in 2003.  Prof. Hartmann is presently an Associate Professor at Northwestern with a 50-50 joint appointment between the departments of Biomedical Engineering and Mechanical Engineering.