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因方法学的不同，年龄对大脑偏侧性变化的影响还存在一些争议。本研究基于高分辨磁共振结构图像，利用多参数模型分析了人脑衰老过程中偏侧性的改变情况。研究共纳入205例被试，按年龄分为7个小组。每名被试的磁共振 T1加权图像用 Freesurfer软件进行前期处理，并计算大脑皮层34个功能区域的形态学特征，包括表面积、平均沟回指数、皮层厚度、皮层下白质体积。用多参数分析方法整合4种特征信息对每组大脑的偏侧性进行评估，同时将具有显著性的P值映射到脑模板上用于可视化。结果表明，随着年龄增加，大脑偏侧性出现全局性的下降，其中以顶叶、枕叶下降最为明显。偏侧性保留或反转的区域主要集中于和高级认知水平相关的区域，这提示大脑在正常衰老过程中可能存在代偿机制以应对认知功能的损伤。该研究为理解神经行为、神经生理疾病提供了新的视角。“,”Age dependence on the hemispheric asymmetry alteration remains inconclusive partially due to the diversity of methodology. In this study, a multivariate model was applied to evaluate the evolution of the structural hemispheric asymmetry during healthy aging based on magnetic resonance imaging data. The T1-weighted images from 205 subjects were retrieved and categorized into 7 age groups. The morphological features including the surface area, mean curvature index, cortical thickness, and subjacent white matter volume in 34 regions of interest were calculated. The multivariate analysis was then performed on each age group to investigate the composite effect of the four features on asymmetry alterations. TheP values were ifnally mapped onto a FreeSurfer template for visualization. Global reduction of hemispheric laterality was identiifed with a worse decline in parietal and occipital lobes as age advances. Reservation and left-right shift of laterality were vastly detected in the high-level cognition-related regions, which may imply a compensatory mechanism of healthy brain counteracting the age-associated functional impairment. The age dependence on the hemispheric asymmetry may embed mechanisms that underlie the behavioral and cognitive declinationassociated with age related neuropsychological diseases.