突触长时程可塑性的动力模型

Dynamical Model of Long-term Synaptic Plasticity

突触长时程可塑性使突触效能加强(长时程增强,LTP)或突触效能减弱(长时程压抑,LTD)是神经系统中潜在的学习和记忆。兴奋神经元突触的LTP和LTD是由突触前和突触后活动的精确定时所诱导。突触长时程可塑性传递改变涉及许多复杂的过程;例如,突触可塑性的两种形式由不同时程的Ca2+进入突触细胞诱导。我们给出了突触可塑性的LTP和LTD合成的过程、动力学模型及突触增强变化的预测模型,当用预测尖峰的不同频率训练和Poisson分布训练时,将产生不同的突触前和突触后的平均电压。

Long-term synaptic plasticity leading to enhancement in synaptic efficacy (long-term potentiation,LTP) or decrease in synaptic efficacy (long-term depression,LTD) is widely regarded as underlying learning and memory in nervous systems. LTP and LTD at excitatory neuronal synapses are observed to be induced by precise timing of pre-and postsynaptic events. Modification of synaptic transmission in long-term plasticity is a complex process involving many pathways; for example,it is also known that both forms of synaptic plasticity can be induced by various time courses of Ca2+ introduction into the postsynaptic cell. We present a phenomenological description of a two-component process for synaptic plasticity and dynamical model。 We give model predictions for changes in synaptic strength when periodic spike trains of varying frequency and Poisson distributed spike trains with varying average frequency are presented pre-and postsynaptically.