Light experience and lateralization of the two visual pathways in the chick
Light experience and lateralization of the two visual pathways in the chick
复制标题
雏鸡的光体验和两条视觉通路的偏侧化
DOI：
10.1016/s0166-4328(98)00094-1
复制
发表时间：
1999
影响因子：
2.7
通讯作者：
C. Deng
中科院分区：
文献类型：
--
作者：
L. Rogers;C. Deng
用荧光示踪剂罗丹明B异氰酸酯（RITC）逆行标记，我们已经研究了组织的离丘脑和离顶盖的视觉投射到前脑的年轻小鸡。此外，我们还研究了孵化前光照对离顶盖视觉投射发育的影响。我们对离丘脑投射的结果证实了以前的发现;即，在男性和女性中，从丘脑左侧到前脑右侧上纹状体的投射比从丘脑右侧到左侧上纹状体的投射更多。组织的tectofugal视觉投射到圆核更对称（男性只检查），虽然有一个趋势，从左侧视顶盖，其同侧核圆比从右侧视顶盖，其同侧核圆更多的预测。从视顶盖到对侧圆形核有许多投射，但与鸽子的报告相反，这些投射中没有明显的不对称。对侧与同侧投射的比率显示，从视顶盖的腹侧区域投射的不对称性和从背侧区域投射的对称性显著。因此，小鸡的两条视觉通路都具有不对称的组织，但在离丘脑通路中的不对称性要大得多。离顶盖投射的轻微不对称性可以通过在孵化前将胚胎暴露于光来确定，如已知的离丘脑投射的情况。
Using retrograde labelling with the fluoroscent tracer rhodamine B isocyanate (RITC), we have examined the organisation of the thalamofugal and tectofugal visual projections to the forebrain of the young chick. In addition, we have investigated the influence of light exposure prior to hatching on the development of the tectofugal visual projections. Our results for the thalamofugal projections confirm those found previously; viz., that there are more projections from the left side of the thalamus to the right hyperstriatum of the forebrain than from the right side of the thalamus to the left hyperstriatum in males and females. The organisation of the tectofugal visual projections to the rotundal nuclei was more symmetrical (males only examined) although there was a trend towards a greater number of projections from the left optic tectum to its ipsilateral nucleus rotundus than from the right optic tectum to its ipsilateral nucleus rotundus. There are numerous projections from the optic tecta to their contralateral rotundal nuclei but, in contrast to reports for the pigeon, no marked asymmetry was present in these. The ratio of contralateral to ipsilateral projections revealed significant asymmetry for projections from the ventral regions of the optic tecta and symmetry from the dorsal regions. Thus both visual pathways of the chick have asymmetrical organisation but the asymmetry is much greater in the thalamofugal pathway. The slight asymmetry in the tectofugal projections may be determined by exposing the embryo to light just before hatching, as known to be the case for thalamofugal projections.