Crain B J, Hall W C
J Comp Neurol. 1980 Sep 15;193(2):403-12. doi: 10.1002/cne.901930207.
After a neonatal lesion of the ipsilateral superior colliculus, the projections to the lateral posterior nucleus from the contralateral superior colliculus and retina expand their terminal fields until they share a common border. In the first experiment described in this paper, we removed both superior colliculi at birth and used the Fink-Heimer method to show that the optic tract projection could expand even further and enter the region which would have been occupied by the terminals of the crossed colliculus projection. Similarly, in the second experiment, we showed that the crossed collicular projection could be increased even more if the contralateral eye as well as the ipsilateral colliculus was removed at birth. Another result of a neonatal superior colliculus lesion is that the projection from the optic tract shares a border with the posterior neocortical projection. In the third experiment, we removed both the ipsilateral superior colliculus and the posterior neocortex at birth and demonstrated that the optic tract projection expanded more than after an ipsilateral colliculus lesion alone. Our results support the hypotheses that the projections from the ipsilateral and contralateral superior colliculi and the retina compete for synaptic space in the lateral posterior nucleus, and that a similar competition between the retinal and cortical projections may also occur.
在同侧上丘发生新生儿期损伤后，来自对侧上丘和视网膜至外侧后核的投射会扩展其终末野，直至它们共享一条共同边界。在本文所述的第一个实验中，我们在出生时切除双侧上丘，并使用芬克 - 海默法显示视束投射甚至可以进一步扩展并进入原本会被交叉上丘投射的终末所占据的区域。同样，在第二个实验中，我们表明，如果在出生时切除对侧眼以及同侧上丘，交叉上丘投射可以增加得更多。新生儿期上丘损伤的另一个结果是，视束投射与新皮质后投射共享一条边界。在第三个实验中，我们在出生时切除同侧上丘和新皮质后区，并证明视束投射的扩展程度比仅切除同侧上丘损伤后的扩展程度更大。我们的结果支持以下假设：来自同侧和对侧上丘以及视网膜的投射在外侧后核中竞争突触空间，并且视网膜和皮质投射之间也可能发生类似的竞争。
