volume_transmitter – Support node for neuromodulated synaptic plasticity¶
The volume transmitter is used in combination with neuromodulated synaptic plasticity, plasticity that depends not only on the activity of the pre- and the postsynaptic neuron but also on a non-local neuromodulatory third signal. It collects the spikes from all neurons connected to the volume transmitter and delivers the spikes to a subset of synapses in the network. The user specifies this subset by passing the volume transmitter as a parameter when a neuromodulatory synapse is defined.
It is assumed that the neuromodulatory signal is a function of the spike times of all spikes emitted by the population of neurons connected to the volume transmitter. The neuromodulatory dynamics is calculated in the synapses itself.
The volume transmitter interacts in a hybrid structure with the
neuromodulated synapses: In addition to the delivery of the
neuromodulatory spikes triggered by every pre-synaptic spike, the
neuromodulatory spike history is delivered at regular time
intervals. The interval is equal to
deliver_interval * d_min,
deliver_interval is an (integer) entry in the parameter
d_min is the minimal synaptic delay.
The implementation is based on the framework presented in 1.
Time interval given in d_min time steps in which the volume signal is delivered from the volume transmitter to the assigned synapses. Must be integer.