美国西北大学Gregory W. Schwartz课题组取得最新进展。他们发现不同类型的视网膜神经节细胞（RGCs）之间的间隙连接产生了偏移的ON-OFF感受野。这一研究成果发表在2020年11月23日出版的《自然-神经科学》上。

他们报告发现F-mini-ON RGC中的ON和OFF受体子域之间的系统空间偏移。令人惊讶的是，此特性并非来自空间偏移的ON和OFF层树突，而是来自通过间隙连接到另一种类型的RGC（F-mini-OFF）的电突触网络。他们表明，这些RGC的不对称形态和连通性可以解释它们的感受野偏移，并且他们使用多单元模型探索了感受野偏移对总体中边缘位置表示精度的影响。这个RGC网络形成了一个新的电通道，在视网膜输出层内结合了ON和OFF前馈通路。

据介绍，在脊椎动物的视网膜中，视觉空间中神经元感受野的位置与突触输入到其树突上的物理位置紧密对应，这种关系称为视网膜位置图。

附：英文原文

Title: An offset ON–OFF receptive field is created by gap junctions between distinct types of retinal ganglion cells

Author: Sam Cooler, Gregory W. Schwartz

Issue&Volume: 2020-11-23

Abstract: In the vertebrate retina, the location of a neuron’s receptive field in visual space closely corresponds to the physical location of synaptic input onto its dendrites, a relationship called the retinotopic map. We report the discovery of a systematic spatial offset between the ON and OFF receptive subfields in F-mini-ON retinal ganglion cells (RGCs). Surprisingly, this property does not come from spatially offset ON and OFF layer dendrites, but instead arises from a network of electrical synapses via gap junctions to RGCs of a different type, the F-mini-OFF. We show that the asymmetric morphology and connectivity of these RGCs can explain their receptive field offset, and we use a multicell model to explore the effects of receptive field offset on the precision of edge-location representation in a population. This RGC network forms a new electrical channel combining the ON and OFF feedforward pathways within the output layer of the retina.

DOI: 10.1038/s41593-020-00747-8

Source: https://www.nature.com/articles/s41593-020-00747-8