TCD Assessment of Hemovelocity while Older Adults Think

本研究计划由两个目标指导：（a）确定已知调节年轻人脑血流速度的认知活动是否会引起老年无卒中患者的类似变化，（B）记录老年人进行这些活动时出现的血流速度时程调节。这些目标导致两个具体目标：（1）验证个体认知活动的效果或。年轻人的速度，和（2）文件相同的认知活动对老年人的速度的影响，无中风的人。为了实现这些目标，三个实验将使用经颅多普勒神经成像程序，同时记录双侧脑血流速度，而人进行认知活动。认知任务模拟日常思维活动，并将从短期记忆，设想人物角色体验，决策，研究刺激和解决基于语言，非语言或定量的问题中选择。两个实验将遵循双向析因设计，在声刺激侧（右侧和左侧）和认知阶段（相关基线和特定任务）进行重复测量。年轻人（实验1）和老年人的大脑中动脉，无中风的人（实验2）将被采样，而他们执行7-9，31秒内的认知任务。30分钟的测试第三个实验将通过添加脑动脉（中、前、后）作为因子扩展为三因素析因设计。将对相同的老年无中风患者的动脉进行采样，以比较认知活动期间可能出现的相对速度差异。这两个目标的实现将提供一个剧目的认知探针从业者作为approxts传统的功能测试，在评估时间弹性的脑血管自动调节机制的老年人，包括那些可能显示脑血管功能障碍。

This research plan is guided by two goals: (a) to determine if cognitive activities known to modulate cerebral hemovelocity in young adults induce comparable changes in older, stroke-free persons, and (b) to document time-course modulations in hemovelocity that emerge while older persons perform these activities. These goals lead to two specific objectives: (1) verify the effects of individual cognitive activities or. the velocities of younger persons, and (2) document the effects of the same cognitive activities on velocities of older, stroke-free persons. To accomplish these objectives, three experiments will use a transcranial Doppler neuroimaging procedure to record bilateral cerebral blood flow velocity simultaneously while persons perform cognitive activities. The cognitive tasks model day-to- day thinking activities and will be selected from short-term remembering, envisaging a persona experience, making decisions, studying stimuli, and solving problems that are language based, nonlanguage based, or quantitative. Two experiments will follow two-way factorial designs, with repeated measures on insonation side (right and left) and cognitive phases (relevant baselines and specific tasks). The middle cerebral artery of young adults (Experiment 1) and older, stroke-free persons (Experiment 2) will be sampled while they perform 7-to-9, 31-sec cognitive tasks within. a 30-min test session. The third experiment will expand to a three-way factorial design by adding cerebral arteries (middle, anterior, posterior) as a factor. The arteries of the same older, stroke-free persons will be sampled to compare relative velocity differences that may emerge during the cognitive activities. Attainment of the two goals will provide a repertoire of cognitive probes to practitioners serving as adjuncts to traditional functional tests in assessing the temporal resiliency to the cerebrovascular autoregulation mechanisms of older persons, including those who may show cerebrovascular dysfunction.