Department of Radiology, Tianjin Medical University General Hospital, Tianjin 300052, PR China.
Neuroimage. 2013 Sep;78:46-58. doi: 10.1016/j.neuroimage.2013.04.011. Epub 2013 Apr 13.
The superior frontal gyrus (SFG) is located at the superior part of the prefrontal cortex and is involved in a variety of functions, suggesting the existence of functional subregions. However, parcellation schemes of the human SFG and the connection patterns of each subregion remain unclear. We firstly parcellated the human SFG into the anteromedial (SFGam), dorsolateral (SFGdl), and posterior (SFGp) subregions based on diffusion tensor tractography. The SFGam was anatomically connected with the anterior and mid-cingulate cortices, which are critical nodes of the cognitive control network and the default mode network (DMN). The SFGdl was connected with the middle and inferior frontal gyri, which are involved in the cognitive execution network. The SFGp was connected with the precentral gyrus, caudate, thalamus, and frontal operculum, which are nodes of the motor control network. Resting-state functional connectivity analysis further revealed that the SFGam was mainly correlated with the cognitive control network and the DMN; the SFGdl was correlated with the cognitive execution network and the DMN; and the SFGp was correlated with the sensorimotor-related brain regions. The SFGam and SFGdl were further parcellated into three and two subclusters that are well corresponding to Brodmann areas. These findings suggest that the human SFG consists of multiple dissociable subregions that have distinct connection patterns and that these subregions are involved in different functional networks and serve different functions. These results may improve our understanding on the functional complexity of the SFG and provide us an approach to investigate the SFG at the subregional level.
额上回（SFG）位于前额皮质的上部，参与多种功能，提示存在功能亚区。然而，人类 SFG 的分割方案和每个亚区的连接模式仍然不清楚。我们首先基于弥散张量纤维束追踪将人类 SFG 分割为前内侧（SFGam）、背外侧（SFGdl）和后（SFGp）三个亚区。SFGam 与前扣带和中扣带皮层解剖相连，这些区域是认知控制网络和默认模式网络（DMN）的关键节点。SFGdl 与中、下额回相连，这些区域参与认知执行网络。SFGp 与中央前回、尾状核、丘脑和额盖相连，这些区域是运动控制网络的节点。静息态功能连接分析进一步表明，SFGam 主要与认知控制网络和 DMN 相关；SFGdl 与认知执行网络和 DMN 相关；SFGp 与感觉运动相关脑区相关。SFGam 和 SFGdl 进一步分为三个和两个亚簇，与布罗德曼区相对应较好。这些发现表明，人类 SFG 由多个可分离的亚区组成，这些亚区具有不同的连接模式，这些亚区参与不同的功能网络并发挥不同的功能。这些结果可能提高我们对 SFG 功能复杂性的理解，并为我们提供了一种在亚区水平上研究 SFG 的方法。
