Schmahmann J D, Pandya D N
Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA.
J Neurosci. 1997 Jan 1;17(1):438-58. doi: 10.1523/JNEUROSCI.17-01-00438.1997.
In our ongoing attempt to determine the anatomic substrates that could support a cerebellar contribution to cognitive processing, we investigated the prefrontal cortical projections to the basilar pons. A detailed understanding of these pathways is needed, because the prefrontal cortex is critical for a number of complex cognitive operations, and the corticopontine projection is the obligatory first step in the corticopontocerebellar circuit. Prefrontopontine connections were studied using the autoradiographic technique in rhesus monkey. The pontine projections were most prominent and occupied the greatest rostrocaudal extent of the pons when derived from the dorsolateral prefrontal convexity, including areas 8Ad, 9/46d, and 10. Lesser pontine projections were observed from the medial prefrontal convexity and area 45B in the inferior limb of the arcuate sulcus. In contrast, ventral prefrontal and orbitofrontal cortices did not demonstrate pontine projections. The prefrontopontine terminations were located preferentially in the paramedian nucleus and in the medial parts of the peripeduncular nucleus, but each cortical area appeared to have a unique complement of pontine nuclei with which it is connected. The existence of these corticopontine pathways from prefrontal areas concerned with multiple domains of higher-order processing is consistent with the hypothesis that the cerebellum is an essential node in the distributed corticosubcortical neural circuits subserving cognitive operations.
在我们持续尝试确定可能支持小脑对认知加工起作用的解剖学基础的过程中，我们研究了前额叶皮质向脑桥基底部的投射。需要详细了解这些通路，因为前额叶皮质对许多复杂的认知操作至关重要，而皮质脑桥投射是皮质脑桥小脑回路中必不可少的第一步。我们使用放射自显影技术在恒河猴中研究了前额叶脑桥连接。当投射源自背外侧前额叶凸面，包括8Ad区、9/46d区和10区时，脑桥投射最为显著，占据脑桥最大的前后范围。从内侧前额叶凸面和弓形沟下肢的45B区观察到较小的脑桥投射。相比之下，腹侧前额叶皮质和眶额皮质未显示出脑桥投射。前额叶脑桥终末优先位于旁正中核和脚周核的内侧部分，但每个皮质区域似乎都有与之相连的独特的脑桥核团组合。这些来自与高阶加工多个领域相关的前额叶区域的皮质脑桥通路的存在，与小脑是服务于认知操作的分布式皮质-皮质下神经回路中的一个重要节点这一假设相一致。
