Cusick C G, Gould H J, Kaas J H
J Comp Neurol. 1984 Dec 10;230(3):311-36. doi: 10.1002/cne.902300302.
Interhemispheric connections of visual cortex were studied in owl monkeys, marmosets, and galagos after multiple injections of horseradish peroxidase into one cerebral hemisphere. Areal patterns of connections were revealed in sections of cortex that was flattened and cut parallel to the surface. Results were related to the locations of known visual areas, especially in owl monkeys, in which more visual areas have been established. The connection patterns in owl monkeys and marmosets are very similar, suggesting that the organization of visual cortex differs little in these two New World simians. Galagos have a basically similar pattern, but the connections are more widespread. In all three primates, connections are not restricted to cortex representing the line of decussation of the retina, and even striate cortex has connections displaced from the border. These connections extend up to 2 mm into area 17 in owl monkeys, and they are most extensive in galagos, where they form foci that are coextensive with regions of high cytochrome oxidase activity. Connections are concentrated in the caudal half of area 18, but protrusions of connections cross of the width of the field. The middle temporal visual area (MT) has unevenly distributed connections throughout, with some increase in density along the border. The dorsomedial visual area (DM) of owl monkeys has connections restricted to the rostral border, and a similar region of sparse connections identifies the probable location of DM in marmosets and galagos. Caudal parts of the dorsolateral visual area (DL) of owl monkeys have dense interhemispheric connections. Other visual areas are characterized by unevenly distributed clumps of connections, suggesting that functions are not uniformly distributed, and that semiregular processing modules exist. The results indicate that most extrastriate visual neurons are subject to interhemispheric influences and support the conclusion that callosal connections are functionally heterogeneous.
在将辣根过氧化物酶多次注射到一只大脑半球后，对枭猴、狨猴和婴猴的视皮质半球间连接进行了研究。在与表面平行切开并展平的皮质切片中揭示了连接的区域模式。结果与已知视觉区域的位置相关，尤其是在枭猴中，已确定了更多的视觉区域。枭猴和狨猴的连接模式非常相似，这表明在这两种新大陆灵长类动物中，视皮质的组织差异很小。婴猴有基本相似的模式，但连接更为广泛。在所有这三种灵长类动物中，连接并不局限于代表视网膜交叉线的皮质，甚至纹状皮质也有从边界移位的连接。这些连接在枭猴中延伸到17区达2毫米，在婴猴中最为广泛，在那里它们形成与高细胞色素氧化酶活性区域共延的焦点。连接集中在18区的后半部分，但连接的突出部分穿过视野宽度。颞中视觉区（MT）的连接分布不均，沿边界密度有所增加。枭猴的背内侧视觉区（DM）的连接局限于吻侧边界，在狨猴和婴猴中，类似的稀疏连接区域确定了DM的可能位置。枭猴背外侧视觉区（DL）的尾部有密集的半球间连接。其他视觉区域的特征是连接团块分布不均，这表明功能并非均匀分布，并且存在半规则处理模块。结果表明，大多数纹外视觉神经元受到半球间的影响，并支持胼胝体连接在功能上是异质的这一结论。
