PDF(Pubmed)
Abstract：
Associations between brain structure and body mass index (BMI) are increasingly gaining attention. Although BMI-related regional alterations in brain morphology have been previously reported, the effect of BMI on the microstructural profiles, which provide information on the proxy of neuronal density within the cortex, is unexplored. In this study, we investigated the links between cortical layer-specific microstructural profiles and BMI in 302 neurologically healthy young adults. Using the microstructure-sensitive proxy based on the T1-and T2-weighted ratio, we estimated microstructural profile covariance (MPC) by calculating linear correlations of cortical depth-wise intensity profiles between different brain regions. Then, low-dimensional gradients of the MPC matrix were estimated using dimensionality reduction techniques, and the gradients were associated with BMI. Significant effects in the heteromodal association areas were observed. The BMI-gradient association map was related to the geodesic distance along the cortical surface, curvature, and sulcal depth, suggesting that the microstructural alterations occurred along the cortical topology. The BMI-gradient association map was further linked to cognitive states related to negative emotions. Our findings may provide insights into understanding the atypical cortical microstructure associated with BMI.
摘要：
大脑结构与体重指数（BMI）之间的关联越来越受到关注。尽管先前已经报道了与BMI相关的大脑形态区域改变，BMI对微观结构的影响，它提供了皮质内神经元密度的代表信息，是未经探索的。在这项研究中,我们在302名神经系统健康的年轻成年人中调查了皮质层特定的微结构特征与BMI之间的联系.使用基于T1和T2加权比率的微观结构敏感代理，我们通过计算不同大脑区域之间皮质深度强度分布的线性相关性来估计微结构分布协方差(MPC).然后，使用降维技术估计MPC矩阵的低维梯度，梯度与BMI相关。观察到异型关联区域的显着影响。BMI-梯度关联图与沿皮质表面的测地距离有关，曲率,和沟深，表明微结构改变是沿着皮质拓扑发生的。BMI-梯度关联图进一步与负面情绪相关的认知状态相关联。我们的发现可能为理解与BMI相关的非典型皮质微观结构提供了见解。
