Competition between synapses located in proximal and distal dendrites of the dentate granule cell through STDP

Abstract

We investigated competition between synapses located proximal and distal dendrites through STDP learning rules using a dentate granule cell model. The proximal dendrite and the distal dendrite were stimulated by a regular pulse train and a random pulse train respectively. When both synapses were subject to asymmetric STDP rules, the distal synapse was not enhanced but the proximal synapse was enhanced through synaptic competition. This competition was caused when the integral of the LTD window was larger than that of the LTP window of the STDP rule in the distal dendrite. In contrast, when the proximal synapse was not subject to the asymmetric STDP rule but a Mexican-hat STDP rule, location of the synapse enhanced by synaptic competition was switched from the proximal synapse to the distal synapse. We also examined the role of inhibitory interneurons in the synaptic competition. © 2009 Springer Berlin Heidelberg.