Computational and Hardware Models of Active Sensing Behaviors

Northwestern University, Evanston IL

Investigators

Abstract

Rats have approximately sixty large facial whiskers that serve as exquisitely sensitive tactile sensors. Tactile information from the whiskers is carried to a brain structure called the trigeminal ganglion, and then to structures called the trigeminal nuclei. This pathway is roughly analogous to the pathway that carries information from the human skin to the brain. Professors Hartmann, Memik, and Ogrenci -Memik are using the rat whisker system as a model to study the process by which animals acquire and refine incoming sensory information to construct representations of the world around them. The research iterates between neurophysiological recordings in the trigeminal nuclei and computational modeling of the observed neural responses. Because the nervous system is massively parallel, the models quickly exceed the limits imposed by conventional computers. The models are therefore being implemented with Field Programmable Gate Arrays (FPGAs), which can effectively replicate the immense parallelism of brainstem circuitry. Notably, the models are built to process data from both real and robotic whiskers, and can be used to generate predictions about physiological responses in the real animal. This work has the potential to have an impact in industry as well as academia. From an industrial perspective, it is likely to inspire studies on unsupervised 3D object recognition using non-optical sensors. Such sensing ability may be useful in a variety of specialized environments. For example, search and rescue robots operating with limited or no vision could potentially use hardware and algorithms similar to those developed here. In neurophysiology, the work is shedding light on processing algorithms common across modalities (vision, audition, somatosensation and proprioception). The work also contributes to strongly-interdisciplinary training at the post-doc, graduate and undergraduate levels, as well as to minority student recruiting. The work also complements graduate-level courses developed by the PI and Co-PIs.