Larkum Matthew E, Nevian Thomas
Department of Physiology, University of Berne, Bern, Switzerland.
Curr Opin Neurobiol. 2008 Jun;18(3):321-31. doi: 10.1016/j.conb.2008.08.013.
Dendritic signal integration is one of the fundamental building blocks of information processing in the brain. Dendrites are endowed with mechanisms of nonlinear summation of synaptic inputs leading to regenerative dendritic events including local sodium, NMDA and calcium spikes. The generation of these events requires distinct spatio-temporal activation patterns of synaptic inputs. We hypothesise that the recent findings on dendritic spikes and local synaptic plasticity rules suggest clustering of common inputs along a subregion of a dendritic branch. These clusters may enable dendrites to separately threshold groups of functionally similar inputs, thus allowing single neurons to act as a superposition of many separate integrate and fire units. Ultimately, these properties expand our understanding about the computational power of neuronal networks.
树突信号整合是大脑信息处理的基本组成部分之一。树突具有突触输入非线性总和的机制,可导致包括局部钠、N-甲基-D-天冬氨酸(NMDA)和钙峰在内的再生性树突事件。这些事件的产生需要突触输入具有独特的时空激活模式。我们假设,最近关于树突峰和局部突触可塑性规则的发现表明,共同输入沿着树突分支的一个子区域聚集。这些簇可能使树突能够分别对功能相似的输入组进行阈值化处理,从而使单个神经元能够作为许多独立的积分发放单元的叠加来发挥作用。最终,这些特性扩展了我们对神经网络计算能力的理解。