早期视觉环境与视觉功能发育

Early visual environment and development of visual function

半个世纪以来,对哺乳动物视觉系统的研究阐明了视网膜-外膝体-视皮层之间复杂而有序的拓扑式神经连接以及视皮层功能的发育过程。视觉神经通路首先是基因遗传、分子及内在电生理活动调控的非视觉经验依赖性发育,然后是动物睁眼后视觉经验调控下的视觉皮层细胞感受野与方位柱、眼优势柱及双眼视觉等功能发育,因此视觉系统的发育是由遗传和环境共同来塑造。本文主要对哺乳动物出生后视觉通路发育过程特别是早期视觉环境对正常视觉功能发育的重要作用作一综述,并探讨通过改善视觉环境以治疗弱视患者的医疗可能性。

Over the past half-century,investigations on mammalian visual system have clarified that the visual pathway from retina to primary visual cortex is highly complex but displays the orderly topologi-cal neural connections.Furthermore,previous explorations especially revealed the function of primary visual cortex and its postnatal development.The development of visual pathway is orchestrated initially by an early innate non-visual experience-dependent regulated by successively genetic,molecules and inher-ent electrophysiological activity,and then visual functions in primary visual cortex such as receptive fields,orientation specific columns,cortical ocular dominance columns and binocular vision etc,are highly regulated by visual experience.Therefore,the development of the visual system is sculpted not on-ly by heredity but also by visual experience after eye opening.This review highlights the postnatal devel-opment of mammalian visual pathway,especially the important effects of early visual environment on the development of normal visual function,and discusses the medical possibilities of improving the treatment of amblyopia by visual environment.