Center for Molecular and Behavioral Neuroscience, Rutgers University, Newark, NJ, 07102, USA; Behavioral and Neural Sciences PhD Program, Rutgers University, Newark, NJ, 07102, USA.
Center for Molecular and Behavioral Neuroscience, Rutgers University, Newark, NJ, 07102, USA.
Neuroimage. 2020 Nov 1;221:117141. doi: 10.1016/j.neuroimage.2020.117141. Epub 2020 Jul 11.
Many studies have identified the role of localized and distributed cognitive functionality by mapping either local task-related activity or distributed functional connectivity (FC). However, few studies have directly explored the relationship between a brain region's localized task activity and its distributed task FC. Here we systematically evaluated the differential contributions of task-related activity and FC changes to identify a relationship between localized and distributed processes across the cortical hierarchy. We found that across multiple tasks, the magnitude of regional task-evoked activity was high in unimodal areas, but low in transmodal areas. In contrast, we found that task-state FC was significantly reduced in unimodal areas relative to transmodal areas. This revealed a strong negative relationship between localized task activity and distributed FC across cortical regions that was associated with the previously reported principal gradient of macroscale organization. Moreover, this dissociation corresponded to hierarchical cortical differences in the intrinsic timescale estimated from resting-state fMRI and region myelin content estimated from structural MRI. Together, our results contribute to a growing literature illustrating the differential contributions of a hierarchical cortical gradient representing localized and distributed cognitive processes.
许多研究通过绘制局部任务相关活动或分布式功能连接（FC），确定了局部和分布式认知功能的作用。然而，很少有研究直接探讨大脑区域局部任务活动与其分布式任务 FC 之间的关系。在这里，我们系统地评估了任务相关活动和 FC 变化的差异贡献，以确定皮质层次结构中局部和分布式过程之间的关系。我们发现，在多个任务中，单模态区域的局部任务诱发活动幅度较大，而跨模态区域的幅度较低。相比之下，我们发现任务状态 FC 在单模态区域相对于跨模态区域显著降低。这揭示了皮质区域之间局部任务活动和分布式 FC 之间的强负相关关系，与先前报道的宏观组织的主要梯度有关。此外，这种分离与从静息态 fMRI 中估计的内在时间尺度以及从结构 MRI 中估计的区域髓鞘含量的皮质层次差异相对应。总之，我们的结果有助于越来越多的文献阐明代表局部和分布式认知过程的分层皮质梯度的差异贡献。
