Delays in auditory-cued step initiation are related to increased volume of white matter hyperintensities in older adults.
Delays in auditory-cued step initiation are related to increased volume of white matter hyperintensities in older adults.
复制标题
听觉提示步骤启动的延迟与老年人白质高信号量的增加有关。
DOI：
10.1007/s00221-008-1443-4
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发表时间：
2008
影响因子：
2
通讯作者：
Redfern,MarkS
中科院分区：
文献类型：
--
作者：
Sparto,PatrickJ;Aizenstein,HowardJ;Vanswearingen,JessieM;Rosano,Caterina;Perera,Subashan;Studenski,StephanieA;Furman,JosephM;Redfern,MarkS
MRI上白质高信号(WMH)的体积增加与老年人的行动能力障碍有关。这项初步研究的目的是调查WMH的体积和听觉提示的步骤启动延迟之间的关系。8名年龄在75-83岁之间的受试者参与了研究。计算皮质脊髓束和丘脑前部的WMH体积。受试者执行听觉提示的步进任务，包括两个简单反应时间(SRT)试验和三个选择反应时间(CRT)试验。SRT试验要求受试者在听觉刺激的情况下，用右脚尽可能快地从对称站立位置步入单一目标位置。在CRT试验中，受试者根据听觉刺激，尽可能快地走到两个可能的位置之一。计算从刺激开始到右脚预期姿势调整(ASTACH)和起跳(LO)的反应时间。与相同位置的SRT步长相比，CRT步长的平均APART和LO更大。WMH的增加与两个靶点的SRT和CRT期间较大的APART和LO显著相关。这些数据表明，WMH体积的增加与自愿步骤启动期间更长的中央处理时间有关，并突显了一种可能的机制，该机制可以帮助解释白质束损伤如何影响老年人的行动能力。
An increased volume of white matter hyperintensities (WMH) on MRI has been associated with mobility impairments in older adults. The objective of this preliminary study was to investigate the relationship between the volume of WMH and the delays in auditory-cued step initiation. Eight subjects aged 75–83 years participated. The WMH volume in the corticospinal tracts and anterior thalamic radiations were summed. Subjects performed an auditory-cued stepping task that included two simple reaction time (SRT) trials and three choice reaction time (CRT) trials. SRT trials required subjects to step as quickly as possible with the right foot from a symmetric standing position to a single target position in response to an auditory stimulus. For the CRT trials, subjects stepped as quickly as possible to one of two possible locations, depending on the auditory stimulus. The time from the stimulus onset to the reaction time of the anticipatory postural adjustment (APART) and liftoff (LO) of the right foot was computed for each stimulus. The mean APARTand LO were greater for the CRT steps compared with the SRT steps to the same location. Increases in WMH were significantly associated with larger APARTand LO during both SRT and CRT for both target locations. These data suggest that increased volume of WMH is associated with greater central processing time during voluntary step initiation, and highlight a possible mechanism that can help to explain how damage to white matter tracts affects mobility in older adults.