# RgcComputeSpikes

### From VISTA LAB WIKI

The **rgcComputeSpikes** function converts cone absorptions into spikes, using a Poisson spiking model.

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## Contents |

# [edit] Introduction

This function comes directly after scene2Absorptions in the pipeline. It computes the spikes of the cells given the absorptions.

[spikes, rgcInterm] = rgcComputeSpikes(absorptions, param, sameLayers, spikeRateGain, saveSpikeData, savingFile, alreadyComputedLinTS);

# [edit] Output

- spikes : Computed spikes, cell structure in which spikes{ii} represents the spikes of the ii-th layer.
- rgcInterm : Intermediate results.

# [edit] Arguments

- absorptions : absorptions computed by scene2Absorptions, if you do not have ISET or for testing purpose, you can still pass a 3D matrix.
- param : rgcParameters object.
- sameLayers : (0 or 1) Do your layers have the same size and connection parameters, if so you can save a lot of time with 1 by computing the connection matrix only once. (default is 0).
- spikeRateGain : gain on the spike rate of the Poisson process, default is 100 (see remarks and the page on spike generation).
- saveSpikeData : 1 if you want to save spiking data to file ('spkHist','spikeIntegralTable','rgcTTable','spikeRate','linTS','spkTS','K', 'cpTRTS', 'fbTRTS', see the page on spike generation for details)
- savingFile : file for saving the spike data
- alreadyComputedLinTS : you can input linTS here to bypass the computation of it and jump directly to spikes computation. This only works with single layers.

# [edit] Example

scene = sceneCreate('slantedBar'); rgcP = rgcParameters; rgcP.addOneLayer('default'); abso = scene2Absorptions(scene,[],[],100,1,[],0.3,1.5); [spikes rgcInterm] = rgcComputeSpikes(abso,rgcP);

# [edit] Remarks

- The different layers are computed in parallel by groups of 4 (limitation due to Matlab) if you have the parallel toolbox in Matlab (and if you don't it should still be fine).

- The intermediate results are stored in the second output rgcInterm. If you are using several layers, and do not ask for it, you can save a lot in memory.

- This function computes the spikes using a Poisson process, with instantaneous rate lambda=exp(rgcV). See the page on spike generation for more details.