Author(s): BOUNY, P., PLACE, U., ARSAC, L.M., DESCHODT-ARSAC, V., Institution: UNIVERSITY OF BORDEAUX, Country: FRANCE, Abstract-ID: 2427

INTRODUCTION:
Sensorimotor rhythm (SMR)-based neurofeedback (NFb) is increasingly investigated as a non-pharmacological strategy to enhance cognitive performance [1]. Given the high cognitive demands of sports environments requiring rapid decision-making, inhibition and sustained attention, SMR-NFb represents a promising tool to optimize athletes’ cognitive functioning. A single SMR-NFb session has been shown to improve selective attention under interference and reorganizes brain-heart coordination reflected in cardiac multifractality [2]. Whether repeated short-term SMR training induces performance-enhancing adaptations beyond acute effects remains unclear. This study examined whether a two-week home-based SMR-NFb program enhances working memory and inhibition, and whether these improvements are accompanied by task-specific changes in nonlinear heart rate variability (HRV).
METHODS:
Twenty-two healthy sport students were randomly assigned to an SMR-NFb group (NFb) or a passive control group (Ctrl). The NFb group completed 8–10 home sessions over two weeks using a portable EEG headband (C3–C4) and a gamified application designed to increase SMR power. Before and after the intervention, participants performed a Stroop task and a 2-back task. Accuracy and response times were extracted. RR intervals were recorded during both tasks using a Polar H10 chest strap (Polar®, Finland). HRV was analyzed using conventional indices (HR, RMSSD, LF, HF, LF/HF) and nonlinear metrics including refined composite multiscale entropy and multifractal detrended fluctuation analysis [3]. Group × Time effects were tested with mixed models; associations were explored using regression analyses.
RESULTS:
A significant Group × Time interaction was observed for 2-back accuracy, with improvement in the NFb group only (p<0.05), while both groups showed reduced response times (main time effect, p<0.001). Stroop accuracy increased selectively after SMR-NFb, particularly for incongruent trials (p<0.05). Classical HRV indices showed no condition-specific effects. In contrast, nonlinear dynamics revealed task-dependent adaptations. During the 2-back task, HRV entropy exhibited stability in the NFb group, whereas a significant increase was observed in the Ctrl group (p<0.05). During the Stroop task, multifractality increased selectively in NFb (p<0.01) with no change in Ctrl. In the NFb group, cognitive gains were associated with increases in SMR relative power during the training sessions.
CONCLUSION:
A two-week tele-neurofeedback program enhances working memory and inhibition beyond acute effects and induces specific reorganizations of nonlinear cardiac dynamics. These findings support SMR-NFb as a promising tool to optimize cognitive performance in sports contexts involving high cognitive demands. In line with previous evidence, entropy and multifractality appear sensitive markers of task-specific cognitive-autonomic modulation over time.

References
[1] Vernon et al., 2003
[2] Bouny et al., 2022
[3] Bouny et al., 2021