Title:
"Sparse coding of time-varying natural images"
Speaker:
Bruno Olshausen, Center for Neuroscience, UC Davis
Subject:
neural coding
Area:
Medicine
Type of school:
university
School name:
ohio state university
Country:
United States
Course language:
English
Course media:
Video
Course duration:
Contributor:
pbp
Comments:
Author: Bruno Olshausen, Center for Neuroscience, UC Davis
Title: "Sparse coding of time-varying natural images"
Streaming Video: Real Media
The images that fall upon our retinae contain certain statistical regularities over space and time. In this talk I will discuss a method for modeling this structure based upon sparse coding in time. When adapted to time-varying natural images, the model develops a set of space-time receptive fields similar to those of simple-cells in the primary visual cortex. A continuous image sequence is thus re-represented in terms of a set of punctate, spike-like events in time. The suggestion is that *both* the receptive fields of V1 neurons and the spiking nature of neural activity go hand in hand---i.e., they are part of a coordinated strategy for producing sparse representations of sensory data.
1. Olshausen, B.A. (in press). Principles of image representation in visual cortex. In The Visual Neurosciences, L.M. Chalupa, J.S. Werner, eds. MIT Press. (Currently available at ftp://redwood.ucdavis.edu/pub/papers/visn-preprint.pdf)
2. Olshausen, B.A., & Field, D.J. (1996). Emergence of simple-cell receptive field properties by learning a sparse code for natural images. Nature, 381, 607-609.
3. Dong, D.W., & Atick, J.J. (1995). Temporal decorrelation: a theory of lagged and nonlagged responses in the lateral geniculate nucleus. Network: Computation in Neural Systems, 6, 159-178.
4. Simoncelli, E.P., & Olshausen, B.A. (2001). Natural image statistics and neural representation. Annual Reviews of Neuroscience, 24, 1193- 1215.
5. van Hateren, J.H., & Ruderman, D.L. (1998). Independent component analysis of natural image sequences yields spatio-temporal filters similar to simple cells in primary visual cortex. Proc.R.Soc.Lond. B, 265, 2315-2320.
pbp