Hi Chao, In real neurons, the refractory period arises from a combination of biophysical mechanisms. After firing an action potential, the cell needs to recover before it can fire another one. In simplified neuron models, such as most integrate-and-fire models, which do not include these recovery mechanisms, one usually adds an explicit refractory period to capture the effect of the biophysical recovery mechanisms in a mathematically or computationally simple way. But if a neuron model includes (slow) recovery variables that will prevent it from spiking for some period after firing a spike, adding an explicit refractory period may not be required. Izhikevich decided that this was the case for his model, and thus there is no explicit refractory period that could be set as a parameter. The neuron model has its refractoriness simply "built in", with details depending on the parameters. Best regards, Hans Ekkehard -- Prof. Dr. Hans Ekkehard Plesser Head, Department of Data Science Faculty of Science and Technology Norwegian University of Life Sciences PO Box 5003, 1432 Aas, Norway Phone +47 6723 1560 Email hans.ekkehard.plesser@nmbu.no<mailto:hans.ekkehard.plesser@nmbu.no> Home http://arken.nmbu.no/~plesser On 10/06/2022, 09:31, "jcye" <jc.ye@foxmail.com<mailto:jc.ye@foxmail.com>> wrote: Some people who received this message don't often get email from jc.ye(a)foxmail.com. Learn why this is important<https://aka.ms/LearnAboutSenderIdentification> Dear NEST Community, When I use NEST, I find that Izhikevich model has no refractory period. Whether there is a specific reason for this setting or whether the model itself does not have this refractory period? After all, according to my understanding, all neurons in biology have the characteristics of refractory period. I would be happy to get any feedback on it. Thanks, Chao.

Dear Charl, Thank you for your reply and recommendation. I think it's very helpful. Best wishes, Chao. &nbsp; ------------------&nbsp;Original&nbsp;------------------ From: "NEST User Mailing List" &lt;nest-users(a)turingbirds.com&amp;gt;om&gt;; Date:&nbsp;Fri, Jun 10, 2022 06:00 PM To:&nbsp;"users"<users@nest-simulator.org&gt;; Subject:&nbsp;[NEST Users] Re: About the Izhikevich model Dear Chao, In case you are interested in developing a variant of the "standard" Izhikevich model from the literature to also include a refractory period, it would be ideal if you could do this in the modeling language NESTML. This allows you to express the model in an easy to understand, but expressive language, and to automatically generate C++ code for it so it can be used in NEST Simulator. In fact, NESTML already has a similar Izhikevich variant in the models database at https://github.com/nest/nestml/blob/master/models/neurons; please see the "izhikevich_psc_alpha.nestml" file in that directory (whereas "izhikevich.nestml" is the standard model). With kind regards, Charl On Fri, Jun 10, 2022, at 09:31, jcye wrote: Dear NEST Community, When I use NEST, I find that Izhikevich model has no refractory period. Whether there is a specific reason for this setting or whether the model itself does not have this refractory period? After all, according to my understanding, all neurons in biology have the characteristics of refractory period. I would be happy to get any feedback on it. Thanks, Chao. _______________________________________________ NEST Users mailing list -- users(a)nest-simulator.org To unsubscribe send an email to users-leave(a)nest-simulator.org