2.2 Synaptic plasticity

Spike-timing dependent plasticity, STDP

• 描述了神经元之间的突触强度如何根据前后spike的相对时间而改变
  • pre-spike before post-spike--> cause LTP
  • post-spike before pre-spike --> cause LTD

LTD

• Because of other stimulation other than presynaptic stimulation, the postsynaptic will be activated before pre synaptic -->
• Low level of $Ca^{2+}$ will get into post synapse through NMDARs-->
• cause activation of phosphatases, and removal of AMPARs, make it harder for later action potential
• 所以说，$Ca^{2+}$的浓度不同，对于记忆的影响不同

LTP

• does LTP = memory?
  • blocking LTP prevents learning
  • Learning induces LTP
  • Reversing LTP removes memories
  • Inducing LTP produces memories
  • So: LTP is very likely involved in memory formation though other processes also likely to contribute
• induction of LTP --> new spine and synapse formation
• experience may result in remapping

Plateau potential

• 持续时间数百毫秒到秒级的去极化状态，电位相对稳定，呈现出平台化状态。