Changes for page 03. Building and simulating a simple model
Last modified by adavison on 2022/10/04 13:55
Summary
-
Page properties (1 modified, 0 added, 0 removed)
Details
- Page properties
-
- Content
-
... ... @@ -84,7 +84,7 @@ 84 84 85 85 PyNN comes with a selection of integrate-and-fire models. We're going to use the IF_curr_exp model, where "IF" is for integrate-and-fire, "curr" means that synaptic responses are changes in current, and "exp" means that the shape of the current is a decaying exponential function. 86 86 87 -This is where we set the parameters of the model: the resting membrane potential is -65 millivolts, the spike threshold is -55 millivolts, the reset voltage after a spike is again -65 millivolts, the refractory period after a spike is one millisecond, the membrane time constant is 10 milliseconds, and the membrane capacitance is 1 nanofarad. We're also going to inject a constant bias current of 1.1 nanoamps into these neurons, so that we get some action potentials.87 +This is where we set the parameters of the model: the resting membrane potential is -65 millivolts, the spike threshold is -55 millivolts, the reset voltage after a spike is again -65 millivolts, the refractory period after a spike is one millisecond, the membrane time constant is 10 milliseconds, and the membrane capacitance is 1 nanofarad. We're also going to inject a constant bias current of 0.1 nanoamps into these neurons, so that we get some action potentials. 88 88 89 89 (% class="box infomessage" %) 90 90 ((( ... ... @@ -166,14 +166,14 @@ 166 166 \\(% style="color:#000000" %)"""Simple network model using PyNN""" 167 167 \\import pyNN.nest as sim(%%) 168 168 (% style="color:#000000" %)from pyNN.utility.plotting import Figure, Panel(%%) 169 -(% style="color:#e74c3c" %)from pyNN.random import RandomDistribution , NumpyRNG(%%)169 +(% style="color:#e74c3c" %)from pyNN.random import RandomDistribution(%%) 170 170 (% style="color:#000000" %)sim.setup(timestep=0.1)(%%) 171 -(% style="color:#e74c3c" %)rng = NumpyRNG(seed=1)(%%) 172 172 (% style="color:#000000" %)cell_type = sim.IF_curr_exp( 173 - (% style="color:#e74c3c" %) v_rest=RandomDistribution('normal', mu=-65.0, sigma=1.0, rng=rng), 174 - v_thresh=RandomDistribution('normal', mu=-55.0, sigma=1.0, rng=rng), 175 - v_reset=RandomDistribution('normal', mu=-65.0, sigma=1.0, rng=rng), (%%) 176 -(% style="color:#000000" %) tau_refrac=1, tau_m=10, cm=1, i_offset=1.1) 172 + (% style="color:#e74c3c" %) v_rest=RandomDistribution('normal', mu=-65.0, sigma=1.0), 173 + v_thresh=RandomDistribution('normal', mu=-55.0, sigma=1.0), 174 + v_reset=RandomDistribution('normal', mu=-65.0, sigma=1.0), (%%) 175 +(% style="color:#000000" %) tau_refrac=1, tau_m=10, cm=1, i_offset=1.1)(%%) 176 + 177 177 178 178 **...** 179 179 ... ... @@ -263,7 +263,7 @@ 263 263 264 264 **...** 265 265 (% style="color:#000000" %)population2.record("v")(%%) 266 -(% style="color:#e74c3c" %)connection_algorithm = sim.FixedProbabilityConnector(p_connect=0.5 , rng=rng)266 +(% style="color:#e74c3c" %)connection_algorithm = sim.FixedProbabilityConnector(p_connect=0.5) 267 267 synapse_type = sim.StaticSynapse(weight=0.5, delay=0.5) 268 268 connections = sim.Projection(population1, population2, connection_algorithm, synapse_type)(%%) 269 269 (% style="color:#000000" %)sim.run(100.0)(%%) ... ... @@ -307,20 +307,19 @@ 307 307 \\(% style="color:#000000" %)"""Simple network model using PyNN""" 308 308 \\import pyNN.(% style="color:#e74c3c" %)neuron(% style="color:#000000" %) as sim(%%) 309 309 (% style="color:#000000" %)from pyNN.utility.plotting import Figure, Panel(%%) 310 -(% style="color:#000000" %)from pyNN.random import RandomDistribution , NumpyRNG(%%)310 +(% style="color:#000000" %)from pyNN.random import RandomDistribution(%%) 311 311 (% style="color:#000000" %)sim.setup(timestep=0.1)(%%) 312 -(% style="color:#000000" %)rng = NumpyRNG(seed=1)(%%) 313 313 (% style="color:#000000" %)cell_type = sim.IF_curr_exp( 314 - v_rest=RandomDistribution('normal', mu=-65.0, sigma=1.0 , rng=rng),315 - v_thresh=RandomDistribution('normal', mu=-55.0, sigma=1.0 , rng=rng),316 - v_reset=RandomDistribution('normal', mu=-65.0, sigma=1.0, rng=rng),317 - tau_refrac=1, tau_m=10, cm=1, i_offset=1.1) 318 -population1 = sim.Population(100, cell_type, label="Population 1") 319 -population2 = sim.Population(100, cell_type, label="Population 2") 313 + (% style="color:#e74c3c" %) (% style="color:#000000" %)v_rest=RandomDistribution('normal', mu=-65.0, sigma=1.0), 314 + v_thresh=RandomDistribution('normal', mu=-55.0, sigma=1.0), 315 + v_reset=RandomDistribution('normal', mu=-65.0, sigma=1.0), (%%) 316 +(% style="color:#000000" %) tau_refrac=1, tau_m=10, cm=1, i_offset=1.1)(%%) 317 +(% style="color:#000000" %)population1 = sim.Population(100, cell_type, label="Population 1")(%%) 318 +(% style="color:#000000" %)population2 = sim.Population(100, cell_type, label="Population 2") 320 320 population2.set(i_offset=0) 321 321 population1.record("v") 322 -population2.record("v") 323 -connection_algorithm = sim.FixedProbabilityConnector(p_connect=0.5 , rng=rng)321 +population2.record("v")(%%) 322 +(% style="color:#000000" %)connection_algorithm = sim.FixedProbabilityConnector(p_connect=0.5) 324 324 synapse_type = sim.StaticSynapse(weight=0.5, delay=0.5) 325 325 connections = sim.Projection(population1, population2, connection_algorithm, synapse_type)(%%) 326 326 (% style="color:#000000" %)sim.run(100.0)(%%) ... ... @@ -356,7 +356,7 @@ 356 356 357 357 Of course, PyNN allows you to create much more complex networks than this, with more realistic neuron models, synaptic plasticity, spatial structure, and so on. You can also use other simulators, such as Brian or SpiNNaker, and you can run simulations in parallel on clusters or supercomputers. 358 358 359 -We will be releasing a series of tutorials, isyear, to introduce these more advanced features of PyNN, so keep an eye on the EBRAINS website.358 +We will be releasing a series of tutorials, throughout the rest of 2021 and 2022, to introduce these more advanced features of PyNN, so keep an eye on the EBRAINS website. 360 360 361 361 (% class="box successmessage" %) 362 362 (((