非成像视觉环路对生理活动和行为的调控作用

Regulation of the non-image-forming visual circuit on physiological activity and behavior

视网膜神经节细胞(RGCs)是视网膜视觉信号输出到大脑的终极神经元,可参与成像视觉(IFV)(图像形成)和非成像视觉(NIFV)(非图像形成)。视觉处理系统除了传递图像的视觉信息外,传入的光信号对人的生理活动和行为也会产生影响,称为NIFV。NIFV较少依赖于传统光感受器细胞产生的信号,而是由视网膜上一类特殊的视网膜感光神经节细胞(ipRGCs)来完成。ipRGCs是RGCs中一类能表达感光黑视蛋白的细胞,其轴突投射至特定核团,参与调控多种NIFV行为,从基础生理调节(如心率和瞳孔大小)到更复杂的行为调节(如昼夜节律),甚至更高层次的认知过程(如焦虑等情绪)。NIFV环路是对光的重要反应,ipRGCs在NIFV环路中起着至关重要的作用。本文就NIFV环路对生理活动和行为的调控作用进行综述,归纳ipRGCs投射核团与NIFV功能的关系,以期为临床医生提供更加全面的视觉认识。

Retinal ganglion cells(RGCs)are final output neurons from the retina to the brain,which can transmit light signals and participate in image-forming vision(IFV)(image formation)and non-image-forming vision(NIFV)(non-image formation).Visual processing system not only transmits visual information of images,but also influences human physiological activities and behaviors by incoming optical signals,which is called NIFV.NIFV relies less on signals generated by conventional photoreceptor cells,but a special class of intrinsically photosensitive retinal ganglion cells(ipRGCs).ipRGCs are a subset of retinal ganglion cells that express melanopsin.The axons of the ipRGCs project to unique targets and modulate a broad range of NIFV behaviors,from basic physiological regulation(such as heart rate and pupil size)to more complex behavioral regulation(such as circadian rhythm)and even higher-level cognitive processes(such as anxiety and other emotions).NIFV circuit is an important response to light,and ipRGCs plays a vital role in NIFV circuit.This article reviewed the regulation of NIFV circuit in physiological activities and behaviors,summarized the relationship between the projections of ipRGCs to the NIFV function,and provided ophthalmologists with more knowledge of visual system.