Alasmar Zaki, Chakravarty M Mallar, Penhune Virginia B, Steele Christopher J
Department of Psychology, Concordia University, Montreal, Quebec, Canada.
School of Health, Concordia University, Montreal, Quebec, Canada.
Hum Brain Mapp. 2025 Jan;46(1):e70079. doi: 10.1002/hbm.70079.
The cortex and cerebellum are densely connected through reciprocal input/output projections that form segregated circuits. These circuits are shown to differentially connect anterior lobules of the cerebellum to sensorimotor regions, and lobules Crus I and II to prefrontal regions. This differential connectivity pattern leads to the hypothesis that individual differences in structure should be related, especially for connected regions. To test this hypothesis, we examined covariation between the volumes of anterior sensorimotor and lateral cognitive lobules of the cerebellum and measures of cortical thickness (CT) and surface area (SA) across the whole brain in a sample of 270 young adults drawn from the HCP dataset. We observed that patterns of cerebellar-cortical covariance differed between sensorimotor and cognitive networks. Anterior motor lobules of the cerebellum showed greater covariance with sensorimotor regions of the cortex, while lobules Crus I and Crus II showed greater covariance with frontal and temporal regions. Interestingly, cerebellar volume showed predominantly negative relationships with CT and predominantly positive relationships with SA. Individual differences in SA are thought to be largely under genetic control while CT is thought to be more malleable by experience. This suggests that cerebellar-cortical covariation for SA may be a more stable feature, whereas covariation for CT may be more affected by development. Additionally, similarity metrics revealed that the pattern of covariance showed a gradual transition between sensorimotor and cognitive lobules, consistent with evidence of functional gradients within the cerebellum. Taken together, these findings are consistent with known patterns of structural and functional connectivity between the cerebellum and cortex. They also shed new light on possibly differing relationships between cerebellar volume and cortical thickness and surface area. Finally, our findings are consistent with the interactive specialization framework which proposes that structurally and functionally connected brain regions develop in concert.
大脑皮层和小脑通过相互的输入/输出投射紧密相连，形成了分离的回路。这些回路被证明将小脑的前叶与感觉运动区域差异连接，将 Crus I 和 Crus II 叶与前额叶区域连接。这种差异连接模式导致了这样一种假设，即结构上的个体差异应该是相关的，尤其是对于相连的区域。为了验证这一假设，我们在从人类连接组计划（HCP）数据集中抽取的 270 名年轻成年人样本中，研究了小脑前感觉运动叶和外侧认知叶的体积与全脑皮质厚度（CT）和表面积（SA）测量值之间的协变关系。我们观察到，感觉运动和认知网络之间的小脑 - 皮质协变模式不同。小脑的前运动叶与大脑皮层的感觉运动区域表现出更大的协变，而 Crus I 和 Crus II 叶与额叶和颞叶区域表现出更大的协变。有趣的是，小脑体积与 CT 主要呈负相关，与 SA 主要呈正相关。SA 的个体差异被认为在很大程度上受遗传控制，而 CT 被认为更容易受经验影响。这表明 SA 的小脑 - 皮质协变可能是一个更稳定的特征，而 CT 的协变可能更受发育影响。此外，相似性度量显示，协变模式在感觉运动叶和认知叶之间呈现出逐渐过渡，这与小脑中功能梯度的证据一致。综上所述，这些发现与小脑和大脑皮层之间已知的结构和功能连接模式一致。它们还为小脑体积与皮质厚度和表面积之间可能存在的不同关系提供了新的见解。最后，我们的发现与交互特化框架一致，该框架提出结构和功能相连的脑区协同发育。
