视网膜神经元回路响应运动目标的生理学建模

Physiological modeling of retinal neuronal circuit's response to moving stimuli

根据模式动物蛙视网膜神经元的生理和信息通路结构,进行了运动目标动态响应的建模和仿真研究.在建立视网膜主要神经元模型的基础上,通过不同的选择和组合仿真来获得不同的输出,分析模式动物获取外界运动目标的信息整合和传输机制,以及由单一刺激因素引起的视觉系统对运动目标动态信息的获取处理和认知过程.研究神经元回路不同连接的动态处理机制,推测响应的认知结果,并与已有生理学数据相比较.结果表明,该视网膜神经元回路模型可以很好地完成对运动目标的检测.讨论了运动目标的检测机制和R3神经元方向选择性响应的形成原因,并分析了感受野时空特性对运动目标检测的影响.

A frog retinal model that accounts for the framework of physiological and information pathways within a frog＇s retinal neurons was studied. With the simplified models of major retinal cell types, different simulation results by varying the selection and combination of these models were generated, which were then used to gain understanding on the mechanism for integrating and transmitting information that the model animal uses to detect moving objects, and analyze how the visual system triggered by a single stimulus dynamically extracts and perceives information from moving objects. Based on analysis of dynamic processing mechanisms of differently connected neuronal circuits, the perceptual results of responses were estimated and compared with known physiological data. Experimental results show that the retinal neuronal circuit model can successfully detect moving stimuli and explain the mechanism of retinal neuronal circuits for detecting moving objects. By applying this model to study the directional selectivity of R3 neurons, the effect of spatiotemporal characteristics of the receptive field on moving-object perception was discussed.