Litvina Elizabeth Y, Chen Chinfei
Department of Neurology,F.M. Kirby Neurobiology Center,Children's Hospital, Boston,Boston,Massachusetts 02115.
Vis Neurosci. 2017 Jan;34:E013. doi: 10.1017/S0952523817000104.
The thalamocortical (TC) relay neuron of the dorsoLateral Geniculate Nucleus (dLGN) has borne its imprecise label for many decades in spite of strong evidence that its role in visual processing transcends the implied simplicity of the term "relay". The retinogeniculate synapse is the site of communication between a retinal ganglion cell and a TC neuron of the dLGN. Activation of retinal fibers in the optic tract causes reliable, rapid, and robust postsynaptic potentials that drive postsynaptics spikes in a TC neuron. Cortical and subcortical modulatory systems have been known for decades to regulate retinogeniculate transmission. The dynamic properties that the retinogeniculate synapse itself exhibits during and after developmental refinement further enrich the role of the dLGN in the transmission of the retinal signal. Here we consider the structural and functional substrates for retinogeniculate synaptic transmission and plasticity, and reflect on how the complexity of the retinogeniculate synapse imparts a novel dynamic and influential capacity to subcortical processing of visual information.
背外侧膝状核(dLGN)的丘脑皮质(TC)中继神经元背负其不准确的名称已有数十年,尽管有确凿证据表明其在视觉处理中的作用超越了“中继”一词所暗示的简单性。视网膜膝状体突触是视网膜神经节细胞与dLGN的TC神经元之间的通信位点。视束中视网膜纤维的激活会引发可靠、快速且强烈的突触后电位,从而驱动TC神经元产生突触后动作电位。数十年来,人们已经知道皮质和皮质下调节系统可调节视网膜膝状体的传递。视网膜膝状体突触在发育完善期间及之后所展现出的动态特性,进一步丰富了dLGN在视网膜信号传递中的作用。在此,我们探讨视网膜膝状体突触传递和可塑性的结构及功能基础,并思考视网膜膝状体突触的复杂性如何赋予视觉信息的皮质下处理一种全新的动态且有影响力的能力。