Sloper J J
Department of Ophthalmology, University Hospital, Queen's Medical Centre, Nottingham, UK.
Eye (Lond). 1993;7 ( Pt 3):319-31. doi: 10.1038/eye.1993.70.
Studies of the effect of visual deprivation on cells in the lateral geniculate nucleus (LGN) show that there are two distinct sensitive periods in the monkey during which different reactions between the visual pathways related to the two eyes predominate and requirements for recovery from deprivation differ. The first extends from birth to about 8 weeks of age. The main interaction between the pathways from the two eyes is competitive, segregation of cortical ocular dominance columns occurs during this early period and monocular deprivation results initially in hypertrophy of undeprived LGN cells, with later parallel shrinkage of both deprived and undeprived parvocellular cells. Simply reopening the closed eye produces no recovery but reverse suture is effective in reversing some of the changes. The second sensitive period starts from about 8 weeks of age, although the peak of the later sensitivity appears to be at 7-9 months of age and some effect is still present at 12-18 months. During this later phase a cooperative interaction between the pathways related to the two eyes is necessary for normal development and in the absence of this selective shrinkage of both deprived and undeprived parvocellular LGN cells occurs. Simply reopening an eye during this late sensitive period allows recovery of these cells to normal size.
对视神经外侧膝状体核（LGN）细胞的视觉剥夺效应研究表明，猴子存在两个不同的敏感期，在此期间，与双眼相关的视觉通路之间会出现不同的反应，且从剥夺状态恢复的要求也有所不同。第一个敏感期从出生持续到约8周龄。来自双眼的通路之间的主要相互作用是竞争性的，在此早期阶段会发生皮质眼优势柱的分离，单眼剥夺最初会导致未剥夺的LGN细胞肥大，随后剥夺和未剥夺的小细胞都会平行萎缩。仅仅重新睁开闭合的眼睛不会产生恢复效果，但反向缝合对于逆转一些变化是有效的。第二个敏感期从约8周龄开始，尽管后期敏感性的峰值似乎出现在7 - 9个月龄，并且在12 - 18个月时仍有一些影响。在这个后期阶段，与双眼相关的通路之间的协同相互作用对于正常发育是必要的，并且在缺乏这种相互作用的情况下，剥夺和未剥夺的小细胞LGN细胞都会发生选择性萎缩。在这个晚期敏感期简单地重新睁开一只眼睛可使这些细胞恢复到正常大小。
