Hi Maryada,

If you have a predetermined current that you want to inject, you can use step_current_generator. This should work well if you have only a limited number of injected currents as suggested by your figure. If you want to inject a very large number of currents, we would need to take another look, since step_current_generator is replicated on all threads, which can cause scaling problems.

If you just want noisy currents, you have the noise_generator for Gaussian noise. If you wanted noise with some amplitude profile (waxing and waning as in the orange and green curves in your plot), one could probably extend noise_generator to modify the noise amplitude with time in similar ways as for the inhomogeneous_poisson_generator. I am not certain if NESTML already provides all that is need to do this or if one still would need to implement this on the C++ level.

Note that noise_generator provides stepwise constant noise with Gaussian-distributed values, not strictly white noise, and is thus dependent on the step size. For details, see

https://nest-simulator.readthedocs.io/en/stable/model_details/noise_generato...

Best, Hans Ekkehard

--

Prof. Dr. Hans Ekkehard Plesser Departmend 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.nomailto:hans.ekkehard.plesser@nmbu.no Home http://arken.nmbu.no/~plesser

From: Maryada Maryada er.maryada@gmail.com Date: Thursday, 18 July 2024 at 14:48 To: NEST User Mailing List users@nest-simulator.org Subject: [NEST Users] Inject analog signal in a neuron Dear NEST Users, Could anyone recommend the best way to inject a fluctuating current over time.

A sample signal [cid:ii_lyr9npif0]

-- Thanks and Regards

Maryada