Reduced Order Modeling of the Lobula Giant Movement Detector

Steve Cox, CAAM at Rice and Fabrizio Gabbiani, Neuroscience at BCM

The Locust Lobula Giant Movement Detector (LGMD) is an identified neuron that responds vigorously to objects approaching on a collision course with the animal. The firing rate of the LGMD peaks when an approaching object approximately reaches a constant angular threshold size on the retina, suggesting that angular threshold might be the variable used to trigger escape and collision avoidance behaviors. This cell has been modeled in fine detail in

Peron SP Krapp HG Gabbiani F (2007) Influence of electrotonic structure and synaptic mapping on the receptive field properties of a collision-detecting neuron, J Neurophysiol, 97:159-177

The project we have in mind is to investigate the extent to which the computational tools of model reduction, as developed by

AR Kellems, D Roos, N Xiao and SJ Cox, (2009) Low-dimensional, morphologically accurate models of subthreshold membrane potential, J Computational Neuroscience.

can be used to reduce the dimension of the LGMD's internal dynamics to a few variables that are essential to its function.