Cerebral white matter integrity mediates adult age differences in cognitive performance.
Cerebral white matter integrity mediates adult age differences in cognitive performance.
复制标题
脑白质完整性介导了认知表现的成年年龄差异。
DOI：
10.1162/jocn.2009.21047
复制
发表时间：
2009-02
影响因子：
3.2
通讯作者：
Huettel SA
中科院分区：
文献类型：
--
作者：
Madden DJ;Spaniol J;Costello MC;Bucur B;White LE;Cabeza R;Davis SW;Dennis NA;Provenzale JM;Huettel SA
之前的研究已经证实，大脑白质完整性的衡量指标会出现与年龄相关的下降，但这种下降在与年龄相关的认知变化中的作用尚不清楚。要得出白质完整性具有中介(因果)贡献的结论，有必要证明白质-认知关系的统计控制降低了年龄-认知关系的大小。在本研究中，我们在涉及词分类的任务转换范式的背景下，测试了白质完整性的中介作用。参与者是20名健康的社区老年人(60-85岁)和20名年轻人(18-27岁)。从弥散张量成像(DTI)纤维束成像，我们得到分数各向异性(FA)作为一个指标的白质完整性的膝部、压部和上纵束(SLF)。平均FA值表现出与年龄相关的下降，与白质完整性的下降一致。从反应时分布模型出发，我们得到了任务绩效的决策成分和非决策成分(知觉-运动)的独立估计。在这两个组成部分中，与年龄相关的下降都很明显。关键的是，任务成绩的年龄差异是由两个区域的FA调节的：膝骨中央部分和右侧大脑半球的压部-顶叶纤维。这种关系只对决策成分成立，在非决策成分中不明显。这一结果首次证明，特定白质束的完整性是与年龄相关的认知能力变化的中介。
Previous research has established that age-related decline occurs in measures of cerebral white matter integrity, but the role of this decline in age-related cognitive changes is not clear. To conclude that white matter integrity has a mediating (causal) contribution, it is necessary to demonstrate that statistical control of the white matter-cognition relation reduces the magnitude of age-cognition relation. In this research, we tested the mediating role of white matter integrity, in the context of a task switching paradigm involving word categorization. Participants were 20 healthy, community-dwelling older adults (60–85 years), and 20 younger adults (18–27 years). From diffusion tensor imaging (DTI) tractography, we obtained fractional anisotropy (FA) as an index of white matter integrity in the genu and splenium of the corpus callosum and the superior longitudinal fasciculus (SLF). Mean FA values exhibited age-related decline consistent with a decrease in white matter integrity. From a model of reaction time distributions, we obtained independent estimates of the decisional and nondecisional (perceptual-motor) components of task performance. Age-related decline was evident in both components. Critically, age differences in task performance were mediated by FA in two regions: the central portion of the genu, and splenium-parietal fibers in the right hemisphere. This relation held only for the decisional component and was not evident in the nondecisional component. This result is the first demonstration that the integrity of specific white matter tracts is a mediator of age-related changes in cognitive performance.
登录
查看更多内容
影响因子：
7.6
作者：
BARON, RM;KENNY, DA
通讯作者：
KENNY, DA
影响因子：
5.7
作者：
Kim, YH;Gitelman, DR;Mesulam, MM
通讯作者：
Mesulam, MM
影响因子：
3.7
作者：
Davis, Simon W.;Dennis, Nancy A.;Cabeza, Roberto
通讯作者：
Cabeza, Roberto
影响因子：
9.9
作者：
Guttmann, CRG;Jolesz, FA;Albert, MS
通讯作者：
Albert, MS
影响因子：
4.2
作者：
Bartzokis, G;Sultzer, D;Cummings, JL
通讯作者：
Cummings, JL