Carandini Matteo, Horton Jonathan C, Sincich Lawrence C
Smith-Kettlewell Eye Research Institute, San Francisco, CA, USA.
J Vis. 2007 Dec 28;7(14):20.1-11. doi: 10.1167/7.14.20.
At many synapses in the central nervous system, spikes within high-frequency trains have a better chance of driving the postsynaptic neuron than spikes occurring in isolation. We asked what mechanism accounts for this selectivity at the retinogeniculate synapse. The amplitude of synaptic potentials was remarkably constant, ruling out a major role for presynaptic mechanisms such as synaptic facilitation. Instead, geniculate spike trains could be predicted from retinal spike trains on the basis of postsynaptic summation. This simple form of integration explains the response differences between a geniculate neuron and its main retinal driver, and thereby determines the flow of visual information to cortex.
在中枢神经系统的许多突触处,高频串列中的动作电位比孤立出现的动作电位更有可能驱动突触后神经元。我们探究了在视网膜膝状体突触处这种选择性的机制是什么。突触电位的幅度非常恒定,排除了诸如突触易化等突触前机制的主要作用。相反,基于突触后总和,可以从视网膜动作电位串列预测膝状体动作电位串列。这种简单的整合形式解释了膝状体神经元与其主要视网膜驱动神经元之间的反应差异,从而决定了视觉信息向皮层的流动。