Chen W, Zhu X H, Thulborn K R, Ugurbil K
Center for Magnetic Resonance Research, Radiology Department, University of Minnesota School of Medicine, 2021 Sixth Street SE, Minneapolis, MN 55455, USA.
Proc Natl Acad Sci U S A. 1999 Mar 2;96(5):2430-4. doi: 10.1073/pnas.96.5.2430.
Subcortical nuclei in the thalamus, which play an important role in many functions of the human brain, provide challenging targets for functional mapping with neuroimaging techniques because of their small sizes and deep locations. In this study, we explore the capability of high-resolution functional magnetic resonance imaging at 4 Tesla for mapping the retinotopic organization in the lateral geniculate nucleus (LGN). Our results show that the hemifield visual stimulation only activates LGN in the contralateral hemisphere, and the lower-field and upper-field visual stimulations activate the superior and inferior portion of LGN, respectively. These results reveal a similar retinotopic organization between the human and nonhuman primate LGN and between LGN and the primary visual cortex. We conclude that high-resolution functional magnetic resonance imaging is capable of functional mapping of suborganizations in small nuclei together with cortical activation. This will have an impact for studying the thalamocortical networks in the human brain.
丘脑的皮质下核团在人类大脑的许多功能中发挥着重要作用，由于其体积小且位置深，利用神经成像技术对其进行功能映射具有挑战性。在本研究中，我们探索了4特斯拉高分辨率功能磁共振成像绘制外侧膝状体（LGN）视网膜拓扑组织的能力。我们的结果表明，半视野视觉刺激仅激活对侧半球的LGN，下视野和上视野视觉刺激分别激活LGN的上部和下部。这些结果揭示了人类和非人类灵长类动物LGN之间以及LGN与初级视觉皮层之间相似的视网膜拓扑组织。我们得出结论，高分辨率功能磁共振成像能够对小核团的亚组织以及皮质激活进行功能映射。这将对研究人类大脑中的丘脑皮质网络产生影响。
