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DOI：
10.1152/physrev.1982.62.2.738
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发表时间：
1982-04
影响因子：
33.6
通讯作者：
中科院分区：
文献类型：
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作者：
大脑结构和功能的发育在多大程度上取决于早期经验是神经科学家的核心兴趣。这个问题在视觉系统中得到了最广泛的研究，也许是因为视觉环境可以相对容易地被操纵。许多实验表明，哺乳动物出生后视觉通路的发育受到生物体早期视觉经验的显著影响。例如，在早期视觉发育过程中，限制模式但允许接近正常水平的漫射光的环境可能会改变神经连接，并在以后的生活中严重降低视觉能力。此外，在相对有限的发育期（关键期）之后，这些改变变得非常困难，如果不是不可能的话，逆转;同样，关键期之后的这种剥夺不会对正常发育的视觉通路产生不利影响。早期的视觉体验可以改变大脑的结构和功能，这一基本观察已经在包括人类在内的各种物种中得到了证实。因此，这是一种普遍现象。研究经验对神经发育的影响有两方面的重要性。首先，它可以提供一种现象学的描述，描述导致特定类型的神经异常的经验。这对于理解系统的延展性非常重要，并且也具有潜在的临床重要性。其次，对早期经验影响的研究可以提供有关正常和异常神经发育机制的信息。也就是说，（人类）大脑中的1010-1014个神经元是如何形成它们令人难以置信的特定互连的，它们被环境改变的机制是什么？我们在这篇综述中的目标是考虑什么是已知的机制，正常和异常的发展，中央视觉通路。而不是简单地提供一个现象学的描述发生在正常和剥夺动物的发展过程中的表面变化，我们试图评估所涉及的潜在过程。在一个贫困的环境中，发育过程中的变化是由萎缩、发育失败还是导致连接改变的活跃但异常的发育引起的？异常的部位是什么，哪些是由于原发性改变而不是系统其他部位发生的变化的继发性反映？正常和异常发育的变化背后是什么样的突触事件？这些突触事件的机制是什么？这些问题和相关问题在本审查中得到解决。关于这些问题的大多数信息都来自对猫视觉系统的研究，尽管许多基本的观察结果已经在其他物种中得到证实，包括灵长类动物。因此我们只能研究猫的视觉系统。我们开始考虑猫的正常视觉通路的组织和功能（第二节）。然后，我们预览一些类的发展机制，
The extent to which development of brain structure and function depends on early experience is of central interest to neuroscientists. This question has been studied most extensively in the visual system, perhaps because of the relative ease with which the visual environment can be manipulated. Many experiments have shown that the postnatal development of mammalian visual pathways is dramatically influenced by the organism’s early visual experience. For example, an environment during early visual development that restricts patterns but allows nearly normal levels of diffuse light can alter neural connections and severely reduce visual capacities later in life. Moreover, after a relatively limited developmental period (the critical period), these alterations become very difficult, if not im, possible, to reverse; similarly, such deprivation after the critical period does not deleteriously affect visual pathways that have developed normally. The basic observation that early visual experience can alter the structure and function of the brain has been verified in a wide variety of species, including humans.. It is thus a general phenomenon.The importance of studying the effects of experience on neural development is twofold. First, it can provide a phenomenological description of the kinds of experience leading to specific types of neural abnormalities. This is important for understanding how malleable the system is, and it is also of potential clinical importance. Second, studies of the effects of early experience can provide information about the mechanisms of both normal and abnormal neural development. That is, how do the 1010-1014 neurons in the (human) brain form their incredibly specific interconnections, and what are the mechanisms by which they are modified by the environment? Our goal in this review is to consider what is known about the mechanisms of normal and abnormal development of the central visual pathways. Rather than simply provide a phenomenological description of the superficial changes occurring during development in normal and deprived animals, we attempt to evaluate the underlying processes involved. Do the changes during development in an impoverished environment result from atrophy, a failure to develop, or active but abnormal development that leads to altered connectivity? What are the sites of the abnormalities, and which are due to primary alterations as opposed to secondary reflections of changes occurring elsewhere in the system? What synaptic events underlie the changes in normal and abnormal development? What are the mechanisms of these synaptic events? These and related issues are addressed in this review. Most information about these issues has derived from studies of the visual system of the cat, although many basic observations have been confirmed in other species, including primates. Therefore we confine ourselves almost exclusiveIy to the cat visual system. We begin by considering the organization and function of the normal visual pathways in the cat (sect. II). Then we preview some classes of developmental mechanisms that have