Hello Evgenia,
I assume you took the brunel_delta_nest model and just replaced the iaf_psc_delta neuron model with iaf_psc_exp_ps.
For the delta-model, each synaptic input causes an instantaneous jump of the membrane potential by J_ex or J_in, respectively. These are given by J in turn and with
the default J=0.1 and g=5, this means excitatory jumps of +0.1 mV and inhibitory jumps of -0.5 mV.
In the iaf_psc_exp* models, on the other hand, the same input weight means that an incoming spike starts a postsynaptic current of 0.1 pA or -0.5 pA, respectively, which
then decays exponentially. The resulting membrane potential change may be noticeably smaller. So I would suggest to increase J to see when you get spiking. Don't worry about increasing J by factors rather than small steps.
To look at details, you could also attach a voltmeter to a few neurons so you can see the membrane potential evolution.
Best regards,
Hans Ekkehard
--
Prof. Dr. Hans Ekkehard Plesser
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
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