Jan's Homepage Spatiotemporal stimulus interactions determine cortical topography Jan Wiemer, Werner von Seelen G ttingen Neurobiology Report 2001, in press. Thieme Abstract Topography and plasticity are two striking characteristics of cortical stimulus representation. Topography means that anatomical coordinates are mapped into the space of represented stimuli in an essentially neighborhood preserving way. This may yield advantages for cortical stimulus processing.
Plasticity means that topographic structures depend dynamically on sensory experience.
We regard topographic structures as equilibrium states determined by incoming stimuli. This is considered as a strategy to change the data format whereas the format of the neural processes operating on the data is kept constant. A universal learning process may generate different topographic structures, and may only allow certain types of stimulus topologies to be transferred into topography. This is realized in a biological plausible way by introducing dynamics in the representational layer of the neural network in the form of propagating waves. Wave dynamics allows spatiotemporal interactions of stimuli within their neural representations.