O'Rawe Jonathan F, Leung Hoi-Chung
Integrative Neuroscience Program, Department of Psychology, Stony Brook University, Stony Brook, NY, United States.
National Institute of Mental Health Intramural Program, National Institutes of Health, Bethesda, MD, United States.
Front Syst Neurosci. 2022 Sep 23;16:966433. doi: 10.3389/fnsys.2022.966433. eCollection 2022.
The striatum is postulated to play a central role in gating cortical processing during goal-oriented behavior. While many human neuroimaging studies have treated the striatum as an undivided whole or several homogeneous compartments, some recent studies showed that its circuitry is topographically organized and has more complex relations with the cortical networks than previously assumed. Here, we took a gradient functional connectivity mapping approach that utilizes the entire anatomical space of the caudate nucleus to examine the organization of its functional relationship with the rest of the brain and how its topographic mapping changes with age. We defined the topography of the caudate functional connectivity using three publicly available resting-state fMRI datasets. We replicated and extended previous findings. First, we found two stable gradients of caudate connectivity patterns along its medial-lateral (M-L) and anterior-posterior (A-P) axes, supporting findings from previous tract-tracing studies of non-human primates that there are at least two main organizational principles within the caudate nucleus. Second, unlike previous emphasis of the A-P topology, we showed that the differential connectivity patterns along the M-L gradient of caudate are more clearly organized with the large-scale neural networks; such that brain networks associated with internal vs. external orienting behavior are respectively more closely linked to the medial vs. lateral extent of the caudate. Third, the caudate's M-L organization showed greater age-related reduction in integrity, which was further associated with age-related changes in behavioral measures of executive functions. In sum, our analysis confirmed a sometimes overlooked M-L functional connectivity gradient within the caudate nucleus, with its lateral longitudinal zone more closely linked to the frontoparietal cortical circuits and age-related changes in cognitive control. These findings provide a more precise mapping of the human caudate functional connectivity, both in terms of the gradient organization with cortical networks and age-related changes in such organization.
纹状体被认为在目标导向行为中对皮层处理起核心作用。虽然许多人类神经影像学研究将纹状体视为一个不可分割的整体或几个同质的部分，但最近的一些研究表明，其神经回路在地形上是有组织的，并且与皮层网络的关系比以前认为的更为复杂。在这里，我们采用了一种梯度功能连接映射方法，利用尾状核的整个解剖空间来研究其与大脑其他部分的功能关系组织，以及其地形映射如何随年龄变化。我们使用三个公开可用的静息态功能磁共振成像数据集定义了尾状核功能连接的地形。我们重复并扩展了先前的发现。首先，我们沿着其内侧-外侧（M-L）和前后（A-P）轴发现了两个稳定的尾状核连接模式梯度，支持了先前对非人类灵长类动物的束路追踪研究结果，即尾状核内至少有两个主要的组织原则。其次，与先前对A-P拓扑结构的强调不同，我们表明沿着尾状核M-L梯度的差异连接模式与大规模神经网络的组织更为清晰；与内部与外部定向行为相关的脑网络分别与尾状核的内侧与外侧范围更紧密相连。第三，尾状核的M-L组织在完整性上显示出更大的与年龄相关的下降，这进一步与执行功能行为测量的年龄相关变化有关。总之，我们的分析证实了尾状核内有时被忽视的M-L功能连接梯度，其外侧纵向区与额顶叶皮层回路以及认知控制的年龄相关变化联系更紧密。这些发现提供了人类尾状核功能连接的更精确映射，无论是在与皮层网络的梯度组织方面，还是在这种组织的年龄相关变化方面。
