Hashikawa T, Van Lieshout D, Harting J K
J Comp Neurol. 1986 Apr 15;246(3):382-94. doi: 10.1002/cne.902460307.
The parabigeminal nucleus receives its major input from the superficial layers of the superior colliculus via the tectoparabigeminal projection. An extensive reciprocal parabigeminotectal pathway has also been observed. This close connectional association between the superficial gray and the parabigeminal nucleus is reflected in the collicularlike response characteristics of parabigeminal neurons (see Sherk: Brain Res. 145:375-379, '78, J. Neurophysiol. 42:1640-1655, 1656-1668, '79a,b, for review). Further documentation of the connectional relationship between the superior colliculus and the parabigeminal nucleus comes from the present data. Thus, our retrograde and anterograde transport findings reveal an extensive projection from the parabigeminal nucleus to layers 3 and 6 and several interlaminar zones of the contralateral dorsal lateral geniculate nucleus. These same layers and interlaminar zones receive tectogeniculate axons and have been shown to contain small cells that project to layers 1 and 3 of area 17. In addition to the distribution of parabigeminal axons to tectally innervated, small-celled zones, considerable parabigeminal input also reaches layers 1 and 5 of the tree shrew lateral geniculate nucleus. Each of these layers is the ipsilaterally (i.e., retinal) innervated component of a matched pair (layers 1 and 2 are considered magnocellular, while 4 and 5 are parvicellular), and it has been shown that layer 1 projects to lamina IVa of area 17, while layer 5 projects to lamina IVB. When the total distribution of parabigeminogeniculate axons is considered, it is apparent that the cells of origin of each of the major (small-celled, parvi- and magnocellular) geniculocortical channels receives parabigeminal input. Such an extensive distribution of parabigeminal axons within the lateral geniculate nucleus suggests that the information they convey might play an important role in geniculocortical function(s).
副视束核通过顶盖-副视束投射从 superior colliculus 的浅层接收其主要输入。还观察到了广泛的副视束-顶盖相互连接通路。上丘浅层灰质与副视束核之间这种紧密的连接关联反映在副视束核神经元的类似上丘的反应特性中（见 Sherk：《大脑研究》145：375 - 379，'78，《神经生理学杂志》42：1640 - 1655，1656 - 1668，'79a，b，以供综述）。上丘与副视束核之间连接关系的进一步证据来自当前的数据。因此，我们的逆行和顺行运输研究结果揭示了从副视束核到对侧背外侧膝状体核的第 3 和第 6 层以及几个层间区的广泛投射。这些相同的层和层间区接收顶盖-膝状体轴突，并且已被证明含有投射到 17 区第 1 和第 3 层的小细胞。除了副视束轴突分布到由顶盖支配的小细胞区外，相当数量的副视束输入也到达树鼩外侧膝状体核的第 1 和第 5 层。这些层中的每一层都是一对匹配层中同侧（即视网膜）支配的成分（第 1 和第 2 层被认为是大细胞层，而第 4 和第 5 层是小细胞层），并且已经表明第 1 层投射到 17 区的 IVa 层，而第 5 层投射到 IVB 层。当考虑副视束-膝状体轴突的总分布时，很明显每个主要的（小细胞、小细胞和大细胞）膝状体-皮质通道的起源细胞都接收副视束输入。副视束轴突在外侧膝状体核内如此广泛的分布表明它们所传递的信息可能在膝状体-皮质功能中起重要作用。
