视网膜神经节细胞感受野的一种新模型 II.神经节细胞方位选择性中心周边相互作用机制

A NEW COMPUTATIONAL MODEL OF RETINALGANGLION CELL RECEPTIVE FIELDS II. MODELING CENTER-SURROUND INTERACTIONS IN ORIENTATIONSELECTIVITY OF A GANGLION CELL RECEPTIVE FIELD WITHEXTENDED DISINHIBITORY AREA

在前文建立的二维视网膜神经节细胞含大周边感受野模型基础上 ,结合生理实验结果模拟了神经节细胞的方位选择性特性。文中采用椭圆感受野的观点解释了方位选择性的成因。并通过中心区以外区域对中心区方位选择性的复杂调制组合 ,展示了感受野不同亚单元对方位选择性的影响作用 ;指出方位选择性的成因是感受野椭圆亚单元的存在;感受野复杂的方位选择性是由于中心和周边在不同刺激条件下竞争的不同结果造成的;同时指出对椭圆感受野 ,倍频反应也会有相应的方位选择性。

This article is based on a two-dimension retinal ganglion cell receptive field model with extended surround described in a previous paper. Based on the physiological data, we simulated some properties of ganglion cell orientation sensitivity. With various stimuli on area outside center, we showed complex effects different subunits on orientation selectivity. We explained the cause for orientation selectivity using elliptical receptive field and pointed out that different receptive field orientation of center and surround results in competitory interaction between them. The modeling results also suggest that the second harmonic frequency components of the response may also have orientation selectivity just as the fundamental frequency one.