Udin S B
J Comp Neurol. 1977 Jun 1;173(3):561-82. doi: 10.1002/cne.901730310.
When the caudal half-tectum is ablated and the optic nerve is cut in adult Rana pipiens, recordings from optic nerve terminals show that the entire visual field comes to be represented in retinotopic order on the remaining rostral half-tectum (compression). In contrast, if the caudal half-tectum is ablated but the optic nerve is left intact, no compression of the retinotectal projection results. Instead, the terminals displaced from the ablated tissue form a permanently disorganized projection to the rostral half-tectum superimposed on the unaltered representation of those parts of the retina which normally project there. The receptive field locations of tectal neurons in both groups of animals show that the altered retinotectal projections make functional synapses. This conclusion is further supported by behavioral data, which show that the accuracy of prey-catching movements is altered in both groups of frogs. The anomalous retinotectal maps can be interpreted by means of a model which includes polarity cues derived from the tectum and ordering cues derived from repelling interactions among fiber terminals.
当成年豹蛙的尾侧半视顶盖被切除且视神经被切断时，对视神经末梢的记录显示，整个视野以视网膜拓扑顺序映射到剩余的吻侧半视顶盖上（压缩）。相反，如果尾侧半视顶盖被切除但视神经保持完整，则不会导致视网膜 - 视顶盖投射的压缩。取而代之的是，从被切除组织移位的末梢形成了一个永久性无序的投射，投射到吻侧半视顶盖上，叠加在视网膜那些正常投射到该处的部分的未改变的映射之上。两组动物中视顶盖神经元的感受野位置表明，改变后的视网膜 - 视顶盖投射形成了功能性突触。行为数据进一步支持了这一结论，该数据表明两组青蛙捕食动作的准确性都发生了改变。异常的视网膜 - 视顶盖图谱可以通过一个模型来解释，该模型包括源自视顶盖的极性线索和源自纤维末梢之间排斥相互作用的排序线索。
