Original Research ARTICLE
Projections of Brodmann Area 6 to the Pyramidal Tract in humans: quantifications using high angular resolution data
- 1Department of Radiology, Xuanwu Hospital, Capital Medical University, China
- 2Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, China
Primate studies indicate that the pyramidal tract (PyT) could originate from Brodmann area (BA) 6. However, in humans, the accurate origin of PyT from BA 6 is still uncertain owing to difficulties in visualizing anatomical features such as the fanning shape at the corona radiata and multiple crossings at the semioval centrum. High angular-resolution diffusion imaging (HARDI) could reliably replicate these anatomical features. We explored the origin of the human PyT from BA 6 using HARDI. With HARDI data of 30 adults from the Massachusetts General Hospital – Human Connectome Project (MGH-HCP) database and the HCP 1021 template (average of 1021 HCP diffusion data), we visualized the PyT at the 30-averaged group level and the 1021 large-sample level and validated the observations in each of the individuals. Endpoints of the fibers within each subregion were quantified. PyT fibers originating from the BA 6 were consistently visualized in all images. Specifically, the bilateral supplementary motor area (SMA) and dorsal premotor area (dPMA) were consistently found to contribute to the PyT. PyT fibers from BA 6 and those from BA 4 exhibited a twisting topology. The PyT contains fibers originating from the SMA and dPMA in BA 6. Infarction of these regions or aging would result in incomplete provision of information to the PyT and concomitant decreases in motor planning and coordination abilities.
Keywords: supplementary motor area, dorsal premotor area, high angular resolution diffusion imaging, pyramidal tract, human connectome project
Received: 30 Apr 2019;
Accepted: 12 Sep 2019.
Copyright: © 2019 Wang, Shan, Zhang, Wei, Li, Yin and Lu. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Mx. Jie Lu, Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China, firstname.lastname@example.org