HIPPOCAMPAL COMMISSURE FUNCTION AND ANATOMY

许多当代的研究都把海马体作为一种结构， 对记忆的重要性。 因此，很明显， 了解什么信息从一个半球传递到另一个半球， 海马连合（HC）。对这个问题的研究， 然而，迄今为止一直被认为是不可接近的，因为接近 背侧HC（dHC）与上覆胼胝体（CC）的粘附 以及对纤维连接性的认识不足， 构成dHC和CC的连续部分。 这种不切实际 现在，人们对相关问题的理解使他们松了一口气。 大脑半球间的通路，提出了一种新的手术策略， 并在实验室里对猕猴进行测试， 视觉/记忆信息通过dHC的半球间传递 单独或与CC的压部结合。 的 在这方面，已经广泛研究了dHC-压体组合。 然而，完全不知道DHC是否共享， 复制或增强了压部的功能， 它是否解释了以前归因于 后者 视觉辨别向一侧半球的转移 通过另一个半球和大脑半球间的识别来学习 将测试呈现的视觉图像;并且，在相同的动物中， 构成dHC的纤维的复杂起源和目的地， 压部和前连合-所有这些都有组件出现 共同从海马旁回-将进行检查。 结果 应该促进对大脑半球间过程及其 与记忆的关系。 此外，由于大脑半球间的加工已经被 在精神分裂症中表现出异常，结果将有助于 基本信息有关的理解的一些 这种复杂精神疾病的症状。

Much contemporary work focuses on the hippocampus as a structure of unique importance for memory. It is thus of obvious interest to understand what information passes from one hemisphere to the other by way of the hippocampal commissure (HC). Examination of this question, however, has heretofore been deemed unapproachable because of the close adherence of the dorsal HC (dHC) to the overlying corpus callosum (CC) and insufficient knowledge about the connectivities of the fibers that constitute the dHC and contiguous parts of the CC. This impracticality is now relieved by emerging understanding of the relevant interhemispheric pathways, which suggest a new surgical strategy, devised and tested in this laboratory on macaques, that will permit testing interhemispheric transfer of visual/mnemonic information across the dHC in isolation, or in conjunction with the splenium of the CC. The dHC-splenium combination has already been extensively studied in this regard; however, it is entirely unknown whether the dHC shares, duplicates, or augments the capabilities of the splenium or, indeed, whether it accounts for some of the properties previously attributed to the latter. The transfer to one hemisphere of visual discriminations learned by the other and interhemispheric recognition of previously presented visual images will be tested; and, in the same animals, the complex origin and destination of fibers that constitute the dHC, splenium, and anterior commissure-all of which have components arising in common from the parahippocampal gyrus-will be examined. The results should advance understanding of interhemispheric processes and their relation to memory. Moreover, since interhemispheric processing has been shown to be abnormal in schizophrenia, the results will contribute fundamental information pertinent to understanding of some of the symptoms of this complex mental disorder.