Coors Annabell, Zeng Weiyi, Ettinger Ulrich, Breteler Monique M B
Population Health Sciences, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.
Cognitive Neuroscience Division, Department of Neurology, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, United States.
Imaging Neurosci (Camb). 2025 Sep 9;3. doi: 10.1162/IMAG.a.138. eCollection 2025.
The human brain is a large-scale network, containing multiple segregated, functionally specialized systems. With increasing age, these systems become less segregated, but the reasons and consequences of this age-related reorganization are largely unknown. Thus, after characterizing age- and sex-specific differences in the segregation of global, sensorimotor, and association systems using resting-state functional MRI data, we analyzed how segregation relates to cognitive performance in both classical and eye movement tasks across age strata and whether this is influenced by the degree of neuropathology. Our analyses included 6,455 participants (30-95 years) of the community-based Rhineland Study. System segregation indices were based on functional connectivity within and between 12 brain systems. We assessed cognitive performance with tests for memory, processing speed, executive function, and crystallized intelligence and oculomotor tasks. Multivariable regression models confirmed that brain systems become less segregated with age (e.g., global segregation: standardized regression coefficient (ß) = -0.298; 95% confidence interval [-0.299, -0.297], p < 0.001) and that in older age this effect is stronger in women compared to men. Higher segregation benefited memory (especially in young individuals) and processing speed in individuals with mild neuropathology (not significant after multiple testing correction). segregation benefited crystallized intelligence in 46- to 55-year-olds. Associations between segregation indices and cognition were generally weak (ß ~ 0.01-0.06). This suggests that optimal brain organization may depend on the degree of brain pathology. Age-related brain reorganization could serve as a compensatory mechanism and partly explain improvements in crystallized intelligence and the decline in fluid cognitive domains from adolescence to (late) adulthood.
人类大脑是一个大规模网络，包含多个分离的、功能专门化的系统。随着年龄的增长，这些系统的分离程度降低，但这种与年龄相关的重组的原因和后果在很大程度上尚不清楚。因此，在使用静息态功能磁共振成像数据表征了全球、感觉运动和联合系统分离中的年龄和性别特异性差异之后，我们分析了分离如何与不同年龄层在经典任务和眼动任务中的认知表现相关，以及这是否受到神经病理学程度的影响。我们的分析纳入了基于社区的莱茵兰研究中的6455名参与者（30至95岁）。系统分离指数基于12个脑系统内部和之间的功能连接性。我们通过记忆、处理速度、执行功能、晶体智力测试和动眼任务来评估认知表现。多变量回归模型证实，脑系统的分离程度随年龄增长而降低（例如，整体分离：标准化回归系数（ß） = -0.298；95%置信区间[-0.299, -0.297]，p < 0.001），并且在老年时，女性的这种效应比男性更强。更高的分离程度对轻度神经病理学个体的记忆（尤其是在年轻人中）和处理速度有益（在多次检验校正后不显著）。分离对46至55岁个体的晶体智力有益。分离指数与认知之间的关联通常较弱（ß约为0.01 - 0.06）。这表明最佳的大脑组织可能取决于脑病理学程度。与年龄相关的大脑重组可能作为一种补偿机制，部分解释了晶体智力的提高以及从青春期到（晚）成年期流体认知领域的下降。
