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Dog.0.0

2007 Feb 9
Summary   This is an 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 largely sustained but somewhat transient, the surround response is delayed relative to that of the center, and the spontaneous firing rate is around 20 spikes/s. A major limitation of this model is that it currently operates only on achromatic stimuli.

Dog.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

• Spatial frequency
• Temporal frequency
• Contrast
• Static phase

Dynamic Random Stimuli

• Random counter-phase vs. contrast
• Random counter-phase vs. SF

Discussion

The TF tuning curve for this model deviates qualitatively from that of a typical LGN cell because the response of the model remains relatively flat at low TFs, instead of decreasing. Perhaps this could be corrected by changing the shape of the negative lobe of the temporal filter to make it extend back further in time, thus giving it more weight to counter to positive lobe.