[MODEL] Implement Cholinergic neurons

[ShravanTata]

• the sum is just the sum of all weighted V0C inputs
• a is the dynamic variable
• tau the time constant
• f_bar is the new output function that still uses the old one
• should be f_bar(V,a)
• we probably should add a weight to it just in case
• f_bar(V,a)=clip(f(v)(1+wa),0,1)
• tau should be a few milliseconds, e.g. 5
• w (maybe not the best letter) =1
• a integrates the V0C input but now has a time constant. it's pretty much a low pass filter of the signal of the sum of V0c inputs.
• so a is 0 when there is no input or some positive number when there is input.
• we use a to amplify the output. So if a>0 we multiply the output by 1+a.
• if the neuron isn't active a doesn't have an effect

the idea is that cholinergic inputs modulate neural firing, i.e. increase the firing rate

[ShravanTata]

Reference papers:

1. Cholinergic Modulation of Locomotor Circuits in Vertebrates