Forskning
January 26, 2015
Effects of caffeine on maltodextrix mouth rinsing on P300, brain imaging and cognitive performance
K De Pauw et al, 2015, Effects of caffeine on maltodextrix mouth rinsing on P300, brain imaging and cognitive performance, Journal of Applied Physiology, published online ahead of print.
Abstract
Objectives: Caffeine (CAF) and maltodextrin (MALT) mouth rinses (MR) improve exercise performance. The current experiment aims at determining the effect of CAF and MALT MR on cognitive performance and brain activity. Methods: Ten healthy male subjects (age: 27±3yrs) completed 3 experimental trials. Each trial included 4 Stroop tasks: 2 familiarization tasks, 1 task before and 1 after MR. The reaction time (ms) and accuracy (%) of simple, congruent and incongruent stimuli were assessed. Electroencephalography was applied throughout the experiment to record brain activity. Amplitudes and latencies of P300 were determined during the Stroop tasks before and after MR. Subjects received MR with CAF (0.3gram/25mL), MALT (1.6gram/25mL) or placebo (PLAC) in a randomized, double-blind cross-over design. During MR, the brain imaging technique standardized low resolution brain electromagnetic tomography was applied. Results and discussion: Magnitude based inferences showed that CAF MR is likely trivial (63.5%) and likely beneficial (36.4%) compared to PLAC MR, and compared to 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 of the accuracy of the 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 cortex.
