How bursts shape the STDP curve in the presence/absence of GABAergic inhibition

Abstract

It has been known for some time that the synapses of the CA1 pyramidal cells are surprisingly unreliable at signalling the arrival of single spikes to the postsynaptic neuron [2]. On the other hand, bursts of spikes are reliably signalled, because transmitter release is facilitated. In the hippocampus, a single burst can produce long-term synaptic modifications. Bursts of spikes in addition to increasing reliability of synaptic transmission [3], they have been shown to provide effective mechanisms for selective communication between neurons in a network [4]. We investigate via computer simulations how the profile of spike-timing-dependent plasticity (STDP) in the CA1 pyramidal cell synapses is affected when an excitatory burst of spikes applied to dendrites is paired with an excitatory single spike applied to the soma in the absence and presence of a 100Hz GABAergic inhibitory spike train applied to the dendrites. We report that the shape of the STDP curve strongly depends on the burst interspike interval in the presence/absence of GABA A when a presynaptic burst and a postsynaptic spike are paired together. © 2009 Springer Berlin Heidelberg.