Antonini A, Stryker M P
W.M. Keck Foundation Center for Integrative Neuroscience, Department of Physiology, University of California San Francisco 94143-0444, USA.
J Comp Neurol. 1996 May 20;369(1):64-82. doi: 10.1002/(SICI)1096-9861(19960520)369:1<64::AID-CNE5>3.0.CO;2-I.
During a critical period in early life, physiological studies reveal that either prolonged or brief periods of monocular occlusion induce similar plastic changes in the primary visual cortex (area 17) of the cat, leading to a nearly complete loss of visual responses from the deprived eye (Hubel and Wiesel [1970], J. Physiol. (London) 160: 106-154). However, the recovery of function is markedly different in the two conditions, being complete and thorough only after a brief period of monocular occlusion (Movshon [1976] J. Physiol. (London) 261: 125-174). In search for anatomical correlates that distinguish between these two experimental conditions, we compared the geniculocortical connectivity in normal kittens with that following brief (4 days and 6-7 days) or prolonged (> 5 weeks) periods of occlusion of vision in one eye. Transneuronal labeling of the geniculocortical pathway revealed changes in both cases, and single afferent arbors reconstructed in serial sections were similarly shrunken after short or long periods of deprivation. However, a significant expansion of the geniculocortical afferents serving the nondeprived eye was evident mainly after prolonged deprivation. These findings provide further evidence for rapid, activity-dependent remodeling of afferents during development.
在生命早期的一个关键时期，生理学研究表明，无论是长时间还是短时间的单眼视觉剥夺，都会在猫的初级视皮层（17区）诱发相似的可塑性变化，导致被剥夺眼的视觉反应几乎完全丧失（休伯尔和威塞尔[1970]，《生理学杂志》（伦敦）160: 106 - 154）。然而，在这两种情况下功能恢复明显不同，只有在短时间单眼视觉剥夺后功能才会完全且彻底恢复（莫夫尚[1976]，《生理学杂志》（伦敦）261: 125 - 174）。为了寻找区分这两种实验条件的解剖学关联，我们比较了正常小猫与一只眼睛经历短时间（4天和6 - 7天）或长时间（> 5周）视觉剥夺后的膝状体 - 皮层连接情况。膝状体 - 皮层通路的跨神经元标记在两种情况下均显示出变化，并且在连续切片中重建的单个传入纤维分支在短期或长期剥夺后同样会缩小。然而，主要在长期剥夺后，为未被剥夺眼服务的膝状体 - 皮层传入纤维有明显的扩张。这些发现为发育过程中传入纤维的快速、活动依赖性重塑提供了进一步的证据。
