Li Peipei, Tsapanou Angeliki, Qolamreza Razlighi R, Gazes Yunglin
Cognitive Neuroscience Division, Department of Neurology, Columbia University Medical Center, 630 W168th Street, P&S Box 16, New York, NY 10032, United States.
Behav Brain Res. 2018 Feb 26;339:249-254. doi: 10.1016/j.bbr.2017.11.005. Epub 2017 Nov 7.
Previous DTI studies have reported associations between white matter integrity and performance on the Stroop interference task. The current study aimed to add to these studies of inhibitory control by investigating how the differences in age and in white matter integrity relate to Stroop performance, and to examine whether the effect of age on Stroop performance is mediated by white matter integrity. 179 healthy adults from 20 to 80 years old were recruited in the study. DTI data were processed through TRACULA and the mean fractional anisotropy (FA) of 18 major white matter tracts were extracted and used for statistical analysis. Correlation analysis showed a strong negative relationship between age and the Stroop interference score (I). Higher I indicated better inhibitory control. Simple linear regression analyses indicated that most of the tracts showed negative relationships with age, and positive relationships with I. Moderation effect of age on the relationship between FA and I was tested on tracts that significantly predicted I after multiple comparison corrections, but none of these moderations were significant. Then we tested if these tracts mediated the effect of age on I and found significant indirect effects of age on I through the FA of the left corticospinal tract and through the right inferior longitudinal fasciculus. Our results highlight the role of a number of major white matter tracts in the processes supporting the Stroop inhibitory performance and further pinpointed the lower white matter integrity of specific tracts as contributors to the decrease in inhibitory control ability associated with the Stroop test in older age.
以往的扩散张量成像（DTI）研究报告了白质完整性与斯特鲁普干扰任务表现之间的关联。本研究旨在通过调查年龄差异和白质完整性差异如何与斯特鲁普任务表现相关，来补充这些关于抑制控制的研究，并检验年龄对斯特鲁普任务表现的影响是否由白质完整性介导。该研究招募了179名年龄在20至80岁之间的健康成年人。DTI数据通过TRACULA进行处理，提取18条主要白质束的平均分数各向异性（FA）并用于统计分析。相关性分析显示年龄与斯特鲁普干扰得分（I）之间存在强烈的负相关关系。I值越高表明抑制控制越好。简单线性回归分析表明，大多数白质束与年龄呈负相关，与I呈正相关。在多次比较校正后对显著预测I的白质束上测试年龄对FA与I关系的调节作用，但这些调节作用均不显著。然后我们测试这些白质束是否介导了年龄对I的影响，发现年龄通过左侧皮质脊髓束的FA和右侧下纵束对I产生显著的间接影响。我们的结果突出了一些主要白质束在支持斯特鲁普抑制表现过程中的作用，并进一步明确了特定白质束较低的白质完整性是导致老年人与斯特鲁普测试相关的抑制控制能力下降的原因。
