Submitted on August 22, 2006
Accepted on October 9, 2006
The Effect of Stochastic Synaptic and Dendritic Dynamics on Synaptic Plasticity in Visual Cortex and Hippocampus
Yidao Cai1, Jeffrey P Gavornik2, Leon N Cooper3, Luk C Yeung3, and Harel Z Shouval1*
1 Neurobiology and Anatomy, University of Texas Medical School at Houston, Houston, Texas, United States
2 Electrical Engineering, University of Texas, austin, Texas, United States
3 Physics, Brown University, Providence, Rhode Island, United States
* To whom correspondence should be addressed. E-mail: harel.shouval{at}uth.tmc.edu.
Various forms of synaptic plasticity, including spike timing-dependent plasticity, can be accounted for by calcium-dependent models of synaptic plasticity. However, recent results in which synaptic plasticity is induced by multi-spike protocols can not simply be accounted for by linear superposition of plasticity due to spike pairs, or by existing calcium dependent models. In this paper we show that multi-spike protocols can be accounted for if, in addition to the dynamics of back-propagating action potentials, stochastic synaptic dynamics are taken into account. We show that a stochastic implementation can account for the data better than a deterministic implementation and is also more robust. Our results demonstrate that differences between experimental results obtained in hippocampus and visual cortex can be accounted for by the different synaptic and dendritic dynamics in these two systems.
