I couldn’t understand what is my exact problem but I already tried different types of input so I believe the problem is not there. And when I look at my plot I couldn’t understand either. I guess I need a synapse equation but could anyone please help me about what is the problem here 
Thanks!
Minimal code to reproduce problem
I convert my “stim” array to TimedArray:
from brian2 import *
my_stim = TimedArray(stim * Hz, dt=1*ms)
tau=10*ms
P = PoissonGroup(1, rates='I_stim(t)')
A = NeuronGroup(100, 'dv/dt = -v/tau : volt', threshold='v > -50*mV', reset='v = -70*mV', refractory=5*ms)
P_A = Synapses(P,A, model='w : volt', on_pre='v += w', delay = 2*ms)
P_A.connect(condition='i != j')
A_M = StateMonitor(A, variables=True, record=True)
A_SM = SpikeMonitor(A)
run(1*second)
plot(A_M.t / ms, A_M[0].v / mV)
ylabel('v (mV)')
xlabel('t (ms)')
show()
plot(A_SM.t/ms, A_SM.i, '.')
xlim(0, 1*second/ms)
show()
Actual output
Hi @SirK ,
It’s hard to tell from your code what exactly is happening here. This code should return an error unless you posted a code snippet.
Below are a few problems:
- there is no variable
stim – TimedArray should return an error
- there is no variable
I_stim – PoissonGroup should return an error
- in the equation for voltage, there is no resting potential – voltage is trying to return back to zero after it is reset to -70mV each time it crosses -50mV. These neurons must oscillate at a pretty high frequency.
- finally, you defined variable
w for synapses P_A "w : volt" but you don’t set this variable to a specific value (like P_A.w=5*mV), but the value by default is zero – spikes from P never effect A.
Hope it helps,
rth
I believe I cannot express myself clearly sorry for that. I dropped the timed array method and wrote some equations for my first neuron group to generate stimulation and solved my problem.
Thank you so much for your effort have a nice day
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