Abstract:
A single bout of exercise improves executive function (EF) and is a benefit - in part -attributed to an exercise-mediated increase in cerebral blood flow enhancing neural efficiency. Limited work has used an event-related protocol to examine postexercise changes in preparatory phase cerebral hemodynamics for an EF task. This is salient given the neural efficiency hypothesis\' assertion that improved EF is related to decreased brain activity. Here, event-related transcranial Doppler ultrasound was used to measure pro- (saccade to target) and antisaccades (saccade mirror-symmetrical target) preparatory phase middle cerebral artery velocity (MCAv) prior to and immediately after 15-min of aerobic exercise. Antisaccades produced longer reaction times (RT) and an increased preparatory phase MCAv than prosaccades - a result attributed to greater EF neural activity for antisaccades. Antisaccades selectively produced a postexercise RT reduction (ps < 0.01); however, antisaccade preparatory phase MCAv did not vary from pre- to postexercise (p=0.53) and did not correlate with the antisaccade RT benefit (p = 0.31). Accordingly, results provide no evidence that improved neural efficiency indexed via functional hyperemia is linked to a postexercise EF behavioural benefit. Instead, results support an evolving view that an EF benefit represents the additive interplay between interdependent exercise-mediated neurophysiological changes.
摘要:
一次运动可以改善执行功能(EF),并且部分归因于运动介导的脑血流增加,从而提高了神经效率。有限的工作使用了与事件相关的协议来检查EF任务的准备阶段脑血流动力学的运动后变化。鉴于神经效率假说断言EF改善与大脑活动减少有关,这一点很明显。这里,使用事件相关的经颅多普勒超声测量有氧运动前15分钟和后15分钟的大脑中动脉速度(MCAv)的前(扫视到目标)和反扫视(扫视镜像对称目标)准备阶段.与前视相比,前视产生了更长的反应时间(RT)和增加的准备阶段MCAv-这一结果归因于反视的EF神经活性更大。运动后RT减少(ps<0.01);然而,反扫视准备阶段MCAv在运动前后没有变化(p=0.53),并且与反扫视RT获益不相关(p=0.31).因此,研究结果未提供证据表明,通过功能性充血建立的神经效率指数提高与运动后EF行为获益相关.相反,结果支持一种不断发展的观点,即EF获益代表了相互依赖的运动介导的神经生理学变化之间的加性相互作用.