De Pauw K, Roelands B, Knaepen K, Polfliet M, Stiens J, Meeusen R
Department of Human Physiology, Faculty of Physical Education and Physical Therapy, Vrije Universiteit Brussel, Brussels, Belgium;
Department of Human Physiology, Faculty of Physical Education and Physical Therapy, Vrije Universiteit Brussel, Brussels, Belgium; Fund for Scientific Research Flanders (FWO), Brussels, Belgium;
J Appl Physiol (1985). 2015 Mar 15;118(6):776-82. doi: 10.1152/japplphysiol.01050.2014. Epub 2015 Jan 22.
Caffeine (CAF) and maltodextrin (MALT) mouth rinses (MR) improve exercise performance. The current experiment aims to determine the effect of CAF and MALT MR on cognitive performance and brain activity. Ten healthy male subjects (age 27 ± 3 yr) completed three experimental trials. Each trial included four Stroop tasks: two familiarization tasks, and one task before and one task after an MR period. The reaction time (in milliseconds) and accuracy (percent) of simple, congruent, and incongruent stimuli were assessed. Electroencephalography was applied throughout the experiment to record brain activity. The amplitudes and latencies of the P300 were determined during the Stroop tasks before and after the MR period. Subjects received MR with CAF (0.3 g/25 ml), MALT (1.6 g/25 ml), or placebo (PLAC) in a randomized, double-blind, crossover design. During MR, the brain imaging technique standardized low-resolution brain electromagnetic tomography was applied. Magnitude-based inferences showed that CAF MR is likely trivial (63.5%) and likely beneficial (36.4%) compared with PLAC MR, and compared with MALT MR likely beneficial to reaction time on incongruent stimuli (61.6%). Additionally, both the orbitofrontal and dorsolateral prefrontal cortex were activated only during CAF MR, potentially explaining the likely beneficial effect on reaction times. MALT MR increased brain activity only within the orbitofrontal cortex. However, this brain activation did not alter the reaction time. Furthermore, no significant differences in the accuracy of stimuli responses were observed between conditions. In conclusion, only CAF MR exerted a likely beneficial effect on reaction time due to the subsequent activation of both the orbitofrontal and dorsolateral prefrontal cortexes.
咖啡因（CAF）和麦芽糊精（MALT）漱口水（MR）可提高运动表现。当前实验旨在确定CAF和MALT MR对认知表现和大脑活动的影响。十名健康男性受试者（年龄27±3岁）完成了三项实验性试验。每项试验包括四项斯特鲁普任务：两项熟悉任务，以及在MR期之前和之后各一项任务。评估了简单、一致和不一致刺激的反应时间（以毫秒为单位）和准确性（百分比）。在整个实验过程中应用脑电图来记录大脑活动。在MR期之前和之后的斯特鲁普任务期间确定P300的振幅和潜伏期。受试者以随机、双盲、交叉设计接受含CAF（0.3 g/25 ml）、MALT（1.6 g/25 ml）或安慰剂（PLAC）的MR。在MR期间，应用了大脑成像技术标准化低分辨率脑电磁断层扫描。基于量级的推断表明，与PLAC MR相比，CAF MR可能作用微小（63.5%）且可能有益（36.4%），与MALT MR相比，可能对不一致刺激的反应时间有益（61.6%）。此外，仅在CAF MR期间眶额皮质和背外侧前额叶皮质被激活，这可能解释了对反应时间的可能有益影响。MALT MR仅在眶额皮质内增加大脑活动。然而，这种大脑激活并未改变反应时间。此外，在不同条件下未观察到刺激反应准确性的显著差异。总之，由于随后眶额皮质和背外侧前额叶皮质均被激活，只有CAF MR对反应时间产生了可能有益的影响。
