http://notebook.kulchenko.com/ By seeking, you will discover... en Paul Kulchenko 2005-12-25T07:17:47Z http://notebook.kulchenko.com/modeling/neural-modeling-synaptic-plasticity <p>Reviewing the code of the <a href="modeling/neural-modeling-spnetplusplus"><span class="caps">SPN</span>et++</a> I realized that the implemented synaptic plasticity mechanism in the simulation is much simpler than I expected. It turned our that the code implements the nearest-neighbor spike model described in <a href="references/papers/relating-stdp-to-bcm"><span class="caps">RELATING</span>-STDP-TO-BCM</a> article by Eugene M. Izhikevich and Niraj S. Desai. According to the authors of the article <em>it may be sufficient to only consider two postsynaptic spikes</em> -- the one that occurs before and the one that occurs after the presynaptic firing -- while determining whether a synapse should be potentiated or depressed based on recent spike activity. In addition to attempting to unify different forms of plasticity -- spike-timing-dependent plasticity (STDP) and a standard long-term potentiation and depression (LTP/LTD) -- into a single framework, this approach appears to be very computationally efficient.</p> <p><strong>update 2006/01/14</strong>: <a href="references/papers/STDP-based-on-local-information"><span class="caps">STDP</span>-BASED-ON-LOCAL-INFORMATION</a> paper presents an alternative rule, which is also described as computationally efficient, yet simple and reliable. This paper also provides five types of gating functions: no gating, presynaptic, postsynaptic, dual OR and dual <span class="caps">AND </span>gating.</p> <p>There is also more information on different types of synaptic plasticity in the post on <a href="modeling/neural-modeling-synaptic-connectivity">synaptic connectivity</a>.</p> modeling/ 2005-12-25T07:17:47Z