Aging Research Center (ARC), Karolinska Institutet and Stockholm University, Tomtebodavägen 18A, 17165, Solna, Sweden.
School of Law, Psychology, and Social Work, Center for Developmental Research (CDR), Örebro University, Örebro, Sweden.
Brain Struct Funct. 2020 Mar;225(2):735-749. doi: 10.1007/s00429-020-02032-7. Epub 2020 Feb 13.
Iron homeostasis is important for maintaining normal physiological brain functioning. In two independent samples, we investigate the link between iron concentration in the basal ganglia (BG) and implicit sequence learning (ISL). In Study 1, we used quantitative susceptibility mapping and task-related fMRI to examine associations among regional iron concentration measurements, brain activation, and ISL in younger and older adults. In Study 2, we examined the link between brain iron and ISL using a metric derived from fMRI in an age-homogenous sample of older adults. Three main findings were obtained. First, BG iron concentration was positively related to ISL in both studies. Second, ISL was robust for both younger and older adults, and performance-related activation was found in fronto-striatal regions across both age groups. Third, BG iron was positively linked to task-related BOLD signal in fronto-striatal regions. This is the first study investigating the relationship among brain iron accumulation, functional brain activation, and ISL, and the results suggest that higher brain iron concentration may be linked to better neurocognitive functioning in this particular task.
铁稳态对于维持正常的生理脑功能很重要。在两个独立的样本中，我们研究了基底神经节（BG）中的铁浓度与内隐序列学习（ISL）之间的联系。在研究 1 中，我们使用定量磁化率映射和与任务相关的 fMRI 来检查区域铁浓度测量值、大脑激活与年轻和年长成人 ISL 之间的关联。在研究 2 中，我们使用来自年龄同质的年长成人 fMRI 数据的指标，研究了脑铁与 ISL 之间的联系。主要有三个发现。首先，在两项研究中，BG 铁浓度与 ISL 呈正相关。其次，ISL 在年轻和年长成人中均表现出稳健性，并且在两个年龄组的额-纹状体区域均发现了与表现相关的激活。第三，BG 铁与额-纹状体区域的与任务相关的 BOLD 信号呈正相关。这是第一项研究脑铁积累、功能大脑激活与 ISL 之间关系的研究，结果表明，较高的脑铁浓度可能与特定任务中更好的神经认知功能有关。
