Neural coding and decoding: lossy compression and local invariances
Date: 9/11/09
Venue: MS020
Time: 2.30 pm
Speaker: Dr. Alex Dimitrov
Affiliation: Center for Computational Biology, Montana State University , USA.
Neural coding and decoding: lossy compression and local invariances
By Dr. Alex Dimitrov
Center for Computational Biology, Montana State University , USA.
Abstract
Biological sensory systems, and more so individual neurons, do not represent external stimuli exactly. This obvious statement is a consequence of the almost infinite richness of the sensory world compared to the relative paucity of neural resources that are used to represent it. Even if the intrinsic uncertainty present in all biological systems is disregarded, there will always be a many-to-one representation of whole regions of sensory space by indistinguishable neural responses. When noise is included, the representation is many-to-many. One direction of research in sensory neuroscience, espoused by us and others, is to identify and model such regions, with the goal of eventually completely describing neural sensory function as the partitioning of sensory space into distinguishable regions, associated to different response states of a sensory system. In essence, our goal is to quantify the distortion function of a particular biological system. The questions we are trying to elucidate currently include: What information about the external world is represented in patterns of neural activity? How is this information used by the nervous system to process sensory stimuli? I will report our progress in these directions.
Short Biography
Dr. Alex Dimitrov started his higher education at Sofia University, Bulgaria. He graduated in 1991 with a BSc in Physics, specializing in Theoretical Physics. He continued his graduate education at the University of Chicago, initially in Physics, where he received his MSc in 1993. He started his doctoral work at the Department of Mathematics, in the Computational and Applied Mathematics Program, under the guidance of Dr. Jack Cowan. Dr. Dimitrov received training in Mathematical and Computational Neurobiology, Cortical Modeling and Biological Information Processing, leading to his doctoral dissertation, “Aspects of Cortical Information Processing”, in which he used techniques from Information Theory to elucidate the functional significance of lateral connections in the primate visual cortex. After graduating from the University of Chicago in 1998, he continued with a postdoctoral research appointment with Dr. John Miller at Montana State University. There he received training in neurophysiology, experimental design and physiological data processing. After three years, he was promoted to Research Assistant Professor in 2001, and to Assistant Professor in Theoretical and Computational Neuroscience in 2003. He is currently teaching and performing research on biological information processing at the Center for Computational Biology, Montana State University. He has been serving the academic community since 1996, as referee for multiple journals, action editor for the Frontiers of Computational Neuroscience, and reviewers for NSF panels. Since 2003, he has been serving at the international Organization for Computational Neuroscience, first as member of the Program Committee, and now as a Board Member. He has also organized and co-organized multiple specialized workshops at NIPS, CoSyNe and CNS.
