Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, UK; Department of Psychology, University of Edinburgh, UK.
Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, UK; Department of Psychology, University of Edinburgh, UK; Scottish Imaging Network, a Platform for Scientific Excellence (SINAPSE) Collaboration, Edinburgh, UK.
Cortex. 2017 Oct;95:92-103. doi: 10.1016/j.cortex.2017.07.021. Epub 2017 Aug 9.
Part B of the Trail Making Test (TMT-B) is widely used as a quick and easy to administer measure of executive dysfunction. The current study investigated the relationships between TMT-B performance, brain volumes, cortical thickness and white matter water diffusion characteristics in a large sample of older participants, before and after controlling for processing speed. Four hundred and eleven healthy, community-dwelling older adults who were all born in 1936 were assessed on TMT-B, 5 tests of processing speed, and provided contemporaneous structural and diffusion MRI data. Significant relationships were found between slower TMT-B completion times and thinner cortex in the frontal, temporal and inferior parietal regions as well as the Sylvian fissure/insula. Slower TMT-B completion time was also significantly associated with poorer white matter microstructure of the left anterior thalamic radiation, and the right uncinate fasciculus. The majority of these associations were markedly attenuated when additionally controlling for processing speed. These data suggest that individual differences in processing speed contribute to the associations between TMT-B completion time and the grey and white matter structure of older adults.
测试的第二部分（TMT-B）被广泛用作一种快速、易于实施的执行功能障碍的测量方法。本研究在控制了加工速度后，在一个大型老年参与者样本中，研究了 TMT-B 表现、脑体积、皮质厚度和白质水扩散特征之间的关系。411 名健康的、居住在社区的老年人接受了 TMT-B、5 项加工速度测试，并提供了同时的结构和扩散 MRI 数据。较慢的 TMT-B 完成时间与额叶、颞叶和下顶叶区域以及大脑外侧裂/脑岛的皮质变薄之间存在显著的关系。较慢的 TMT-B 完成时间也与左侧前丘脑辐射和右侧钩束的白质微观结构较差显著相关。当另外控制加工速度时，这些关联中的大多数明显减弱。这些数据表明，加工速度的个体差异导致 TMT-B 完成时间与老年人的灰质和白质结构之间的关联。
