ignore_and_fire
ignore_and_fire - Neuron generating spikes at fixed intervals irrespective of inputs
Description
The ignore_and_fire neuron is a neuron model generating spikes at a predefined firing_rate with a constant inter-spike interval (“fire”), irrespective of its inputs (“ignore”). In this simplest version of the ignore_and_fire neuron, the inputs from other neurons or devices are not processed at all (*). The ignore_and_fire neuron is primarily used for neuronal-network model verification and validation purposes, in particular, to evaluate the correctness and performance of connectivity generation and inter-neuron communication. It permits an easy scaling of the network size and/or connectivity without affecting the output spike statistics. The amount of network traffic is predefined by the user, and therefore fully controllable and predictable, irrespective of the network size and structure.
To create asynchronous activity for a population of ignore_and_fire neurons, the firing phase``s can be randomly initialised. Note that the firing ``phase is a real number, defined as the time to the next spike relative to the firing period.
(*) The model can easily be extended and equipped with any arbitrary input processing (such as calculating input currents with alpha-function shaped PSC kernels or updating the gating variables in the Hodgkin-Huxley model) or (after-) spike generation dynamics to make it more similar and comparable to other non-ignorant neuron models. In such extended ignore_and_fire models, the spike emission process would still be decoupled from the intrinsic neuron dynamics.
Note
This neuron model can only be used in combination with a fixed simulation resolution (timestep size).
Parameters
Name |
Physical unit |
Default value |
Description |
|---|---|---|---|
firing_rate |
Bq |
10.0Bq |
firing rate |
State variables
Name |
Physical unit |
Default value |
Description |
|---|---|---|---|
phase |
real |
1.0 |
relative time to next spike (in (0,1]) |
phase_steps |
integer |
firing_period_steps / 2 |
start halfway through the interval by default |
Equations
Source code
The model source code can be found in the NESTML models repository here: ignore_and_fire.