The Role of Excitatory and Inhibitory Synaptic Connectivity in the Pattern of Bursting Behavior in a Pyramidal Neuron Model

The connections between excitatory and inhibitory synapses are significant for generation of busting activity in a pyramidal neuron model. We have suggested in previous studies that a reduced neuronal model of synaptically connected neurons could produce repetitive bursting activity. We have also suggested that the modification of the balance between inhibition and excitation by synaptic weight could alter the excitability of neuronal networks. In this computational study, we have investigated the role of the relative locations of excitatory and inhibitory synapses on the dendritic tree and soma in the generation of bursting activity. We have built a reduced pyramidal neuron model of synaptically connected neurons using the simulation software GENESIS. Our model consists of three reduced pyramidal neurons and an inhibitory interneuron. Simulations show that a reduced pyramidal neuron model can accurately replicate bursting behavior. This bursting activity depends upon the synaptic parameters represented by synaptic weight and delay as well as the locations of synaptic inputs. Simulations with an interneuron show that the inhibitory interneuron regulates neuronal bursting activity. The inhibitory effect is stronger when the inhibitory synapse is close to the soma.