Foster R E, Hall W C
J Comp Neurol. 1975 Oct 15;163(4):397-425. doi: 10.1002/cne.901630403.
The goals of this study were: (1) to describe the total pattern of projections from the optic tectum of Iguana iguana and Pseudemys scripta; and (2) to describe the contributions of particular lamina of the Iguana's optic tectum to this total pattern. Lesions were made in the optic tectum of the Iguana which damaged either all or only certain tectal laminae and, for comparison with the Iguana, lesions in the turtle's optic tectum were made which involved all laminae. The anterograde degeneration resulting from these lesions was stained with the Fink-Heimer ('67) method. The total pattern of projections from the optic tectum in the Iguana and the turtle is similar to that reported for representatives of other vertebrate classes. That is, the optic tectum gives rise to ipsilateral ascending projections to pretectal nuclei, to nucleus rotundus and to nucleus geniculatus lateralis pars ventralis of the diencephalon and, in addition, to a contralateral ascending pathway which courses via the supraoptic decussation to the contralateral diencephalon. Tectotectal connections and several descending pathways were also recognized in each species. The descending pathways include ipsilateral tectobulbar and tecto-isthmi pathways and a contralateral predorsal bundle. Lesions which damaged only certain tectal laminae in the Iguana revealed a laminar organization of the efferent projections. A lesion restricted to the superficial retinal-recipient layers, stratum griseum et album superficiale, resulted in degeneration in only nucleus isthmi pars magnocellularis and nucleus geniculatus lateralis pars ventralis. A lesion which involved both the retinal-recipient layers and stratum griseum centrale resulted in degeneration in only one additional structure, nucleus rotundus. A small lesion involving the deep periventricular layers as well as the superficial layers produced degeneration in the predorsal bundle and the ipsilateral tectobulbar tract as well as in the structures receiving input from the more superficial layers. These results are compared to the results of similar analyses of the superior colliculus in mammals.
（1）描述鬣蜥和伪龟视顶盖的投射总体模式；（2）描述鬣蜥视顶盖特定层对这一总体模式的贡献。在鬣蜥的视顶盖制造损伤，损伤要么破坏所有顶盖层，要么仅破坏某些顶盖层，并且，为了与鬣蜥作比较，在龟的视顶盖制造涉及所有层的损伤。这些损伤导致的顺行性退变用芬克 - 海默（1967年）法进行染色。鬣蜥和龟视顶盖的投射总体模式与其他脊椎动物类代表的情况相似。也就是说，视顶盖发出同侧上行投射至顶盖前核、圆核以及间脑的外侧膝状体腹侧部，此外，还发出一条对侧上行通路，该通路经视交叉上连合至对侧间脑。在每个物种中还识别出顶盖 - 顶盖连接和几条下行通路。下行通路包括同侧顶盖 - 延髓和顶盖 - 峡部通路以及一条对侧背前束。在鬣蜥中仅破坏某些顶盖层的损伤揭示了传出投射的分层组织。局限于视网膜接受的浅层即浅灰层和浅白层的损伤仅导致峡部大细胞部核和外侧膝状体腹侧部核的退变。涉及视网膜接受层和中央灰层的损伤仅导致另外一个结构即圆核的退变。一个涉及脑室周围深层以及浅层的小损伤导致背前束和同侧顶盖 - 延髓束以及接受来自较浅层输入的结构发生退变。将这些结果与哺乳动物上丘的类似分析结果进行比较。
