Journal of Neuroscience Methods, 94, 165–175. Mapping of fiber orientation in human internal capsule by means of polarized light and confocal scanning laser microscopy. Lecture on localization of cerebral and spinal disease. However, most of our patients had lesions in the cranial dorsal part of the internal capsule, where the pyramidal tract may not be completely rotated yet. So the rotation does have to take place in the median between precentral gyrus and brain stem, and IC is just the median. It is well‐known that somatotopy of hand is located lateral to the foot in the centrum semiovale (Seo, Chang, & Jang, 2012 Zolal et al., 2012), but in the brainstem, the distribution is reversed, meaning that somatotopy of hand is located medial to the foot (Hong, Son, & Jang, 2010 Kwon, Hong, & Jang, 2011). Or perhaps, they are all right, the difference just means the different level of the structure of IC. On the one hand, this indicates overlap between leg fibers and hand fibers in the IC on the other hand, this might be the reason why their result conflicts with both Holodny et al. Interestingly, 45% of total leg responses co‐occurred with arm responses. Using electrophysiology, the authors found that face fibers were located anteromedial to hand responses, while foot fibers lied posterolateral to the hand representation. ![]() However, a recent study (Duerden, Finnis, Peters, & Sadikot, 2011) investigating the somatotopic organization and probabilistic mapping of motor responses in the IC found a contrasting result. ![]() Moreover, they calculated the ratio of the lesion compared with the PLIC and found that the most overlapping area was the median of the PLIC. ( 2013) suggested that the corticobulbar tracts pass through the median of the PLIC instead of the genu. Holodny, Gor, Watts, Gutin, and Ulu ( 2005) demonstrated that the corticospinal tracts are located in the posterior third quarter of the PLIC and that hand fibers are located anterolateral to foot fibers. ![]() Neither of these two findings fits the classical distribution of descending fibers in the PLIC, supporting previous studies casting doubt on the classical anatomy (Englander, Netsky, & Adelman, 1975 Kretschmann, 1988 Yagishita, Nakano, Oda, & Hirano, 1994). In brief, there are two main findings: first, hand fibers seem to be located laterally to foot fibers in the short axis of PLIC second, face fibers are likely located in the anteromedial portion of the posterior limb of the IC. In the other way, the 0.348, the mean “AB/AD” of group Y suggests that face fibers cannot just locate in the anterior third of PLIC, let alone the genu of IC. And the mean “AB/AD” of group N, 0.46, suggests that the face fibers locate in the anteromedial portion of the PLIC. The difference between “∠AOB” of group A and group B suggests that the hand fibers locate laterally to foot fibers in the short axis of PLIC.
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