Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA; Northwestern University Interdepartmental Neuroscience Program, Northwestern University, Evanston, IL 60208, USA.
Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA; Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA; Department of Neurobiology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL 60208, USA.
Neuron. 2022 Jul 6;110(13):2110-2123.e4. doi: 10.1016/j.neuron.2022.04.012. Epub 2022 May 3.
Retinal ganglion cells (RGCs) are the spiking projection neurons of the eye that encode different features of the visual environment. The circuits providing synaptic input to different RGC types to drive feature selectivity have been studied extensively, but there has been less research aimed at understanding the intrinsic properties and how they impact feature selectivity. We introduce an RGC type in the mouse, the Bursty Suppressed-by-Contrast (bSbC) RGC, and compared it to the OFF sustained alpha (OFFsA). Differences in their contrast response functions arose from differences not in synaptic inputs but in their intrinsic properties. Spike generation was the key intrinsic property behind this functional difference; the bSbC RGC undergoes depolarization block while the OFFsA RGC maintains a high spike rate. Our results demonstrate that differences in intrinsic properties allow these two RGC types to detect and relay distinct features of an identical visual stimulus to the brain.
视网膜神经节细胞（RGCs）是眼睛的放电投射神经元，可对视觉环境的不同特征进行编码。为了驱动特征选择性，已经对向不同 RGC 类型提供突触输入的回路进行了广泛研究，但对于理解内在特性及其如何影响特征选择性的研究较少。我们在小鼠中引入了一种 RGC 类型，即爆发抑制型对对比（bSbC）RGC，并将其与 OFF 持续型 alpha（OFFsA）RGC 进行了比较。它们的对比反应功能的差异不是源于突触输入的差异，而是源于内在特性的差异。产生尖峰是这种功能差异背后的关键内在特性；bSbC RGC 经历去极化阻断，而 OFFsA RGC 保持高尖峰率。我们的结果表明，内在特性的差异使这两种 RGC 类型能够检测和传递相同视觉刺激的不同特征到大脑。
