Department of Neurosurgery, Hospital Universitario Marqués de Valdecilla, Santander, Cantabria, Spain.
Cortex. 2010 May;46(5):691-9. doi: 10.1016/j.cortex.2009.07.015. Epub 2009 Aug 29.
Despite electrostimulation studies of the white matter pathways, supporting the role of the inferior fronto-occipital fasciculus (IFOF) in semantic processing, little is known about the precise anatomical course of this fascicle, especially regarding its exact cortical terminations. Here, in the lights of these new functional data, we dissected 14 post-mortem human hemispheres using the Klingler fiber dissection technique, to study the IFOF fibers and to identify their actual cortical terminations in the parietal, occipital and temporal lobes. We identified two different components of the IFOF: (i) a superficial and dorsal subcomponent, which connects the frontal lobe with the superior parietal lobe and the posterior portion of the superior and middle occipital gyri, (ii) a deep and ventral subcomponent, which connects the frontal lobe with the posterior portion of the inferior occipital gyrus and the posterior temporo-basal area. Thus, our results are in line with the hypothesis of the functional role of the IFOF in the semantic system, by showing that it is mainly connected with two areas involved in semantics: the occipital associative extrastriate cortex and the temporo-basal region. Further combined anatomical (dissection and Diffusion Tensor Imaging) and functional (intraoperative subcortical stimulation) studies are needed, to clarify the exact participation of each IFOF subcomponent in semantic processing.
尽管对大脑白质纤维束的电刺激研究支持下额枕束（IFOF）在语义处理中的作用，但对于该束的确切解剖路径知之甚少，特别是其确切的皮质终止点。在这里，根据这些新的功能数据，我们使用 Klingler 纤维解剖技术解剖了 14 个死后的人类大脑半球，以研究 IFOF 纤维，并确定它们在顶叶、枕叶和颞叶中的实际皮质终止点。我们确定了 IFOF 的两个不同成分：（i） 浅层和背侧亚成分，连接额叶与上顶叶和上、中回的后段；（ii） 深层和腹侧亚成分，连接额叶与下枕回的后段和颞底后区。因此，我们的结果与 IFOF 在语义系统中的功能作用假说一致，表明它主要与两个涉及语义的区域相连：枕叶联合的外纹状体和颞底区。需要进一步进行联合解剖学（解剖和弥散张量成像）和功能学（术中皮质下刺激）研究，以阐明每个 IFOF 亚成分在语义处理中的确切参与。
