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Title Synaptic acticity - Learning in neural systems
Author Lehn-Schiøler, Tue (Informatics and Mathematical Modelling, Technical University of Denmark, DTU, DK-2800 Kgs. Lyngby, Denmark)
Olesen, Lars Spicker
Institution Technical University of Denmark, DTU, DK-2800 Kgs. Lyngby, Denmark
Thesis level Master's thesis
Year 2002
Abstract Based on the findings that certain types of Long Term Potentiation (LTP) and Long Term Depression (LTD) are found to be dependent on the inflow of Ca following a postsynaptic depolarization, a model of synaptic plasticity is proposed. This is done by the suggestion of an `imaginary' function, the conversion function, intended to mimic the underlying behavior of the Ca level. The model incorporates the dynamic effects, depression and facilitation, found to occur at specific synapses, caused by presynaptic depletion and presynaptic residual Ca phenomena. The proposed model combines the short term dynamics with the longer lasting plastic effects. The computational implications are investigated and it is found that like the model proposed by Song et al. this synapse produces stable competitive learning. The model involves some level of biological realism as it demonstrated the ability to comply with the features seen in connection with long term potentiation: Cooperativity, associativity, and specificity.
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Admin Creation date: 2006-06-22    Update date: 2007-09-11    Source: dtu    ID: 58320    Original MXD