Graduate Program in Neuroscience, The University of Western Ontario, 1151 Richmond St, London, ON, N6A 3K7, Canada.
School of Kinesiology, Faculty of Health Sciences, The University of Western Ontario, 1151 Richmond St, London, ON, N6A 3K7, Canada.
Exp Brain Res. 2024 Sep;242(9):2193-2205. doi: 10.1007/s00221-024-06879-8. Epub 2024 Jul 16.
A single bout of exercise as well as exposure to a hypercapnic environment increases cerebral blood flow (CBF) and is an adaptation linked to a post-intervention executive function (EF) benefit. In the present investigation we sought to determine whether a transient reduction in CBF impairs EF. Accordingly, we employed 10-min -30 mmHg and -50 mmHg lower-body negative pressure (LBNP) interventions as well as a non-LBNP control condition. LBNP was employed because it sequesters blood in the lower legs and safely and reliably decreases CBF. Transcranial Doppler ultrasound was used to measure middle cerebral artery velocity (MCAv) to estimate CBF prior to and during LBNP conditions. As well, assessments of the inhibitory control component of EF (i.e., antipointing) were completed prior to (pre-) and immediately after (i.e., post-) each condition. Antipointing requires that an individual reach mirror-symmetrical to an exogenously presented target and is a task providing the resolution to detect subtle EF changes. Results showed that LBNP produced a 14% reduction in MCAv; however, null hypothesis, equivalence and Bayesian contrasts indicated that antipointing metrics did not vary from pre- to post-intervention, and LBNP-based changes in MCAv magnitude were not reliably correlated with antipointing planning times. Hence, a 10-min reduction in CBF did not impact the efficiency or effectiveness of an inhibitory control measure of EF.
单次运动以及暴露于高碳酸环境都会增加脑血流（CBF），这是一种与干预后执行功能（EF）益处相关的适应。在本研究中，我们试图确定 CBF 的短暂降低是否会损害 EF。因此，我们采用了 10 分钟-30mmHg 和-50mmHg 的下肢负压（LBNP）干预以及非 LBNP 对照条件。采用 LBNP 是因为它可以将血液困在小腿中，并安全可靠地降低 CBF。经颅多普勒超声用于测量大脑中动脉速度（MCAv），以在 LBNP 条件之前和期间估计 CBF。此外，在每个条件之前（预）和之后（后）立即完成 EF 的抑制控制成分（即，反向指向）的评估。反向指向要求个体到达与外部呈现的目标镜像对称的位置，并且是一个可以检测到细微 EF 变化的任务。结果表明，LBNP 使 MCAv 降低了 14%；然而，零假设、等效性和贝叶斯对比表明，从干预前到干预后，反向指向指标没有变化，并且 MCAv 幅度的 LBNP 变化与反向指向计划时间没有可靠相关。因此，CBF 减少 10 分钟并不影响 EF 抑制控制措施的效率或效果。
