UMIT-University of Health Sciences Medical Informatics and Technology, Institute of Psychology, Hall in Tirol, Austria.
Department of Psychology, University of Jaén, Jaén, Spain.
Psychophysiology. 2019 Mar;56(3):e13305. doi: 10.1111/psyp.13305. Epub 2018 Nov 19.
In addition to symptoms including fatigue, dizziness, reduced drive, or mood disturbance, individuals with chronic low blood pressure (hypotension) frequently report cognitive complaints. While attentional deficits have been empirically confirmed, it is still unknown whether the impairments also encompass executive functions. This study investigated cerebral blood flow modulations in hypotension during a precued antisaccade/prosaccade task requiring the executive function of proactive inhibition in addition to preparatory attention. Using functional transcranial Doppler sonography, bilateral blood flow velocities in the middle cerebral arteries (MCA) were recorded in 39 hypotensive and 40 normotensive participants. In the task, a stimulus appeared left or right of a fixation point 5 s after a cuing stimulus; subjects had to move their gaze to the mirror image position of the stimulus (antisaccade) or toward it (prosaccade control condition). Video-based eye tracking was used for ocular recording. A right dominant MCA blood flow increase arose during task preparation, which was smaller in hypotensive than normotensive participants. In addition, hypotensive participants exhibited lower peak velocity of the saccadic response. The extent of the reductions in blood flow and task performance in hypotension did not differ between antisaccade and prosaccade conditions. The smaller MCA flow increase may reflect reduced activity in the dorsolateral prefrontal and inferior parietal cortices during proactive inhibition and preparatory attention in hypotension. Given that group differences in blood flow and performance arose independent of task complexity and executive function load, hypotension may be characterized by basic attentional impairments rather than particular executive function deficits.
除了疲劳、头晕、性欲降低或情绪紊乱等症状外，慢性低血压（低血压）患者常报告认知投诉。虽然注意力缺陷已被经验证实，但仍不清楚这些损伤是否也包括执行功能。本研究调查了在需要执行功能的前提示反扫视/前扫视任务中低血压期间的大脑血流调制，该任务除了预备注意外还需要主动抑制。使用功能 transcranial 多普勒超声，在 39 名低血压和 40 名正常血压参与者中记录了大脑中动脉（MCA）的双侧血流速度。在任务中，刺激在提示刺激后 5 秒出现在注视点的左侧或右侧；受试者必须将目光移到刺激的镜像位置（反扫视）或朝向它（前扫视控制条件）。基于视频的眼动追踪用于眼球记录。在任务准备期间出现了右侧 MCA 血流增加，低血压参与者的血流增加小于正常血压参与者。此外，低血压参与者的扫视反应峰值速度较低。在低血压中，血流和任务表现的减少程度在反扫视和前扫视条件之间没有差异。MCA 血流增加较小可能反映了在低血压中主动抑制和预备注意期间背外侧前额叶和下顶叶皮层活动减少。鉴于血流和表现的组间差异独立于任务复杂性和执行功能负荷，低血压可能表现为基本注意力损伤，而不是特定的执行功能缺陷。
