Dear Nosratullah,
sorry, can you perhaps rephrase your question? It is unclear what you mean by "make the area under the synaptic current constant".
In networks with conductance based synapses, there is no such thing as *the* synaptic current. For conductance based synapses, the current I_ij(t)=g_ij(t)*(V_i(t)-E_j) at synapse j->i is determined by the membrane potential V_i(t) of the target cell i, which, in turn, is affected by the synaptic currents at all synapses of this neuron (for point neurons). As the membrane potential V_i(t) is strongly fluctuating in balanced networks, the synaptic-current responses I_ij(t) triggered by input spikes from neuron j are different (in shape) for each incoming spike, even if the weight and time constant of the conductance kernel are fixed.
You can of course easily preserve the area
A = \int dt g_ij(t) = w_ij * tau
under the exponential conductance kernel
g_ij(t)=w_ij * exp(-t/tau) * H(t)
(with H(t)=Heaviside function) by compensating a change in its amplitude w_ij ("weight") by the time constant tau = A/w_ij. But this won't make I_ij(t) constant.
Best, Tom
On 06.05.20 11:19, Nosratullah M wrote:
Dear all,
I hope you are in staying safe. I'm working on a balanced network consisting of "iaf_cond_exp" neurone model. I want to have the control over these parameters at the same time:
- increasing the synaptic decay time.
- reducing the synaptic weight.
The goal is to make the area under the synaptic current, constant. So that we know that the only parameter that is affecting on the network, is synaptic delay. I wonder if you know of any furmula in mathematics or any algorithm, that can help me, making this process automatic. And keeping the area under the curve, a constant value.
Best wishes, Nosratullah
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-- --- Dr. Tom Tetzlaff Institute of Neuroscience and Medicine (INM-6) Computational and Systems Neuroscience & Institute for Advanced Simulation (IAS-6) Theoretical Neuroscience Jülich Research Centre and JARA Jülich, Germany
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