Responses of CA1 pyramidal neurons: comparing the effects of dendritic and somatic inputs

This work investigates the effect of synaptic input location on both single cell dynamics and small network behavior. Using spike time response curves (STRCs), we measure how synaptic inputs effect the expected firing time of a periodically firing cell. By changing the input location from the soma, the most convenient place to record, to the dendrite, where excitatory synaptic inputs occur biologically, we see a difference in the effects of these inputs. Dendritic inputs given early in the interspike interval (ISI) causes the greatest advance of the expected spike time. Somatic inputs advance the expected spike time most when given later in the ISI. The differences between the STRCs translate to differences in synchrony properties in a simulated small network. Two cell networks with excitatory synapses connected via their somas fire synchronously; however, two cell networks with excitatory synapses connected through their dendrites fire anti-synchronously. These results have implications for larger neural networks.