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Jacquet, T.

Publications and source records attributed to Jacquet, T..

3 recordsLinked to original sources

Motor learning under mental fatigue: the compensatory role of rest periods

Mental fatigue is known to impair cognitive and motor performance, but its impact on motor learning remains unclear. This study examined how mental fatigue affects skill acquisition in a sequential finger-tapping task. Twenty-eight participants were assigned to either a mental fatigue group, which completed a thirty-minute Stroop task, or a control group, which watched a documentary of equivalent duration. Both groups then trained on the finger-tapping task across multiple practice blocks with brief rest periods. Overall motor skill improved similarly in both groups. However, mental fatigue altered the pattern of acquisition: participants in the fatigue group showed decreased performance during practice blocks, which was compensated by larger gains during inter-block rest periods. A strong negative correlation was observed between online decrements and offline improvements, indicating that greater declines during practice were associated with larger gains during rest. This study highlights the critical role of rest periods in maintaining learning under cognitively demanding conditions and provides insight into how internal states, such as mental fatigue, can selectively influence the expression of performance without compromising overall learning.

neuroscience↗

Multimodal Dynamics of Mental Fatigue and Their Selective Modulation by Acute Exercise: Effects on Memory and Creativity

Mental fatigue (MF) arises from sustained cognitive load and produces a multisystem signature spanning subjective experience, task performance, cortical oscillations, and oculomotor dynamics. It may alter higher-order cognitive functions essential to everyday life, underscoring the need for preventive strategies. Although moderate aerobic exercise (EXO) facilitates recovery from MF, its influence on the onset and expression of MF when performed beforehand remains unexplored. This study provided a multimodal characterization of MF, assessed its impact on associative memory and divergent creativity, and examined whether prior EXO modulated these outcomes. Twenty-nine participants completed either 15 min of EXO or rest before a 35-min MF-inducing Time Load Dual Back task. Subjective fatigue and effort, performance, EEG activity, and eye-blink rate were continuously recorded; associative memory and divergent creativity were assessed pre-intervention and post-MF. Both groups showed progressive increases in MF and effort from 7 min onward, stable performance, and a rise in parieto-central alpha power at 18 min. The EXO group exhibited higher frontal-medial theta power and stable blink rates, whereas blink rate in REST increased at 21 min. EXO did not prevent subjective MF nor influence behavioral stability but modulated neurophysiological markers potentially related to compensatory control and dopaminergic regulation. Associative memory remained preserved in both groups, whereas creative flexibility increased in REST but not EXO, suggesting MF-related disinhibition in the former and preserved inhibitory control in the latter. These findings refine temporal and multimodal profile of MF and highlight the need to optimize exercise parameters and task demands to enhance preventive efficacy and guide interventions.

neuroscience↗

Exploring dynamic brain oscillations in motor imagery and low-frequency sound

While both motor imagery (MI) and low-frequency sound listening have independently demonstrated the ability to modulate brain activity, there remains an unexplored frontier regarding the potential synergistic effects that may arise from their combined application. Any further modulation derived from this combination may be relevant for motor learning and/or rehabilitation. We conducted an experiment probing the electrophysiological activity of brain during these processes. By means of EEG, we recorded alpha and beta band power amplitude, which serve as markers of brain activity. Twenty volunteers were instructed to i) explicitly imagine finger flexion/extension movements in a kinaesthetic modality, ii) listen to low-frequency sounds, iii) imagine finger flexion while listening to low-frequency sounds, and iv) stay at rest. We observed a bimodal distribution, suggesting the presence of variability in brain activity across participants during both MI and low-frequency sound listening. One group of participants (12 individuals) displayed increased alpha power within contralateral sensorimotor and ipsilateral medial parieto-occipital regions during MI. Another group (8 individuals) exhibited a decrease in alpha and beta band power within sensorimotor areas. Interestingly, low-frequency sound listening elicited a similar pattern of brain activity within both groups. Surprisingly, the combination of MI and sound listening did not result in additional changes in alpha and beta power amplitudes compared to these processes in isolation, regardless of group. Altogether, these findings shed significant insight into the brain activity and its variability generated during MI and low-frequency sound listening. Nevertheless, it appears that the simultaneous engagement of MI and low-frequency sound listening could not further modulate alpha power amplitude, possibly due to concurrent cortical activations. This prompts us to inquire whether administering these interventions sequentially could uncover any additional modulation.

neuroscience↗