Neural mechanisms for generating rate and temporal codes in model CA3 pyramidal cells

The effect of synaptic inhibition on burst firing of a two-compartment mode l of a CA3 pyramidal cell is considered. We show that, depending on its tim ing, a short dose of fast decaying synaptic inhibition can either delay or advance the timing of firing of subsequent bursts. Moreover, increasing the strength of the inhibitory input is shown to modulate the burst profile fr om a full complex burst, to a burst with multiple spikes, to single spikes. We additionally show how slowly decaying inhibitory input can be used to s ynchronize a network of pyramidal cells. Implications for the phase precess ion phenomenon of hippocampal place cells and for the generation of tempora l and rate codes are discussed.