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Following the tutorial for the Python interface to the NEST simulator I have created 2 neuron populations and connected them:

import nest
ndict = {"I_e": 200.0, "tau_m": 20.0}
nest.SetDefaults("iaf_psc_alpha", ndict)
neuronpop1 = nest.Create("iaf_psc_alpha", 100)
neuronpop2 = nest.Create("iaf_psc_alpha", 100)

nest.Connect(neuronpop1, neuronpop2, syn_spec={"weight":20.0})

But how could I connect them with a specific synapse model like the ones listed in the model directory?

Robin De Schepper
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1 Answers1

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If I understand the question correctly, you want to connect neurons with specific connectivity patterns.

The default connection pattern of nest.Connect is "all_to_all".

More details about the available patterns are detailed in the Connect documentation.

You can also see the available rules by calling nest.ConnectionRules().

If you're using ipython or jupyter, you can get the docstring locally by typing nest.Connect?.

EDIT: to change synapse type (how it transmits incoming signals), please see the "synapse types" documentation.

You can find examples for tsodyks or quantal_stdp synapses.

An example with your populations would be:

# connect populations with depressing synapses
dep_params = {"U": 0.67, "u": 0.67, 'x': 1.0, "tau_rec": 450.0,
              "tau_fac": 0.0, "weight": 250.}

nest.CopyModel("tsodyks_synapse", "dep_syn", syn_param)

nest.Connect(neuronpop1, neuronpop2, syn_spec="dep_syn")

for synapses where close subsequent spikes would have less and less effect on the post-synaptic neuron.

Silmathoron
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  • No I'd like to know how to select by which synapse the neurons are being connected to eachother. For example how could I connect `neuronpop1` to `neuronpop2` through the `Tsodyks2Connection` listed in the Model Directory? Or am I conceptually misunderstanding something? – Robin De Schepper Aug 05 '20 at 17:44
  • Oh ok, so from review of the `Connect` documentation I see that it is the "synapse type" that I want to set, I incorrectly called that a "connection model" I'll update my question. Could you give an example in your answer that uses something else than the default `static_synapse` and sets some of its attributes? – Robin De Schepper Aug 05 '20 at 17:46
  • updated the answer with an example using a dynamic tsodyks synapse – Silmathoron Aug 06 '20 at 19:27