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DogSust.0.0

2007 Feb 8

Summary   This is a sustained ON-center spiking unit. It consists of a center-surround difference-of-Gaussian linear receptive field and a Poisson spike generator. This simple model captures some of the tuning properties of a typical macaque parvocellular LGN cell for achromatic stimuli. The response is sustained, the surround response is delayed relative to that of the center, and the spontaneous firing rate is between 20 and 30 spikes/s. Typically, however, parvocellular cells are not perfectly sustained, and this model represents the extreme of a completely sustained response. A major limitation of this model in terms of representing p-cells is that it does not account for color sensitivity.

DogSust.0.0.mod

Data

Results

The results here were obtained using this response file, which records spikes from an ON-center unit near the center of the stimulus grid.

Sine Tuning

Dynamic Random Stimuli

Discussion

In response to the random counter-phase stimuli, the STA shape for this model does not change with contrast. This is consistent with the behavior of typical parvocellular LGN cells, which lack the contrast gain control that is evident in magnocellular cells.