Biology subjects

Pageaux, B.

Publications and source records attributed to Pageaux, B..

14 recordsLinked to original sources

bioRxiv2026

Increased perceived effort during contralateral thermal heat pain is not explained by increased intracortical and corticospinal inhibition.

BackgroundPain influences motor function and has been proposed to reduce corticospinal and intracortical excitability. At the same time, performance can be maintained during pain, at the cost of increased perceived effort, a centrally generated signal reflecting resource engagement. Here, we tested whether contralateral thermal heat pain-related changes in corticospinal and intracortical excitability contribute to increased effort perception. MethodsIn this preregistered transcranial magnetic stimulation (TMS) study, twenty-one healthy participants received single and paired pulse TMS at rest and during submaximal isometric right wrist flexions performed at 20% maximal peak force. Trials were conducted under a control condition or during contralateral thermal stimulation (painful or non-painful warm) applied to the left forearm. After each contraction, participants rated the intensity of their perceived effort. Corticospinal and intracortical excitability of the right wrist flexor was assessed at rest and during submaximal contractions. ResultsContralateral heat pain significantly increased perceived effort compared with the control and warm conditions. Contralateral heat pain did not reduce corticospinal or intracortical excitability. Conversely, contralateral heat pain increased corticospinal excitability, reflected primarily in decreased cortical silent period duration. Perceived effort was associated with the subjective experience of pain rather than with TMS-derived variables. ConclusionsThese findings suggest that increased effort during contralateral heat pain cannot be attributed to inhibition of the primary motor cortex or the corticospinal pathway. The higher perceived effort in the presence of contralateral heat pain likely reflects the cognitive cost of pain rather than alterations in the transmission of the motor command.

neuroscience↗

bioRxiv2026

Facing pain is effortful: key role of the supplementary motor area and anterior midcingulate cortex

Pain captures attention and interferes with executive and motor processes. In the presence of pain, increasing effort may represent a compensatory mechanism to counteract pain-related disruption and maintain task performance. In this preregistered fMRI study, we investigated neural mechanisms underlying preserved task performance during pain and increased perceived effort. Forty right-handed participants performed a visuomotor force-matching task consisting of isometric handgrip contractions at a low and high force levels under individually calibrated painful or non-painful thermal stimulation. Thermal stimulation was applied to the left forearm, and participants rated the intensity of perceived effort after each isometric contraction. Maintaining task performance under pain was associated with increased perceived effort and recruited brain regions involved in pain modulation and cognitive control. Region-of-interest analysis showed perceived effort was consistently linked to decreased anterior midcingulate cortex activity, whereas supplementary motor area contributions varied depending on its role in motor execution or pain processing. Across experimental condition, motor, pain-modulatory and cognitive-control regions were associated with effort perception. Independently of condition, effort perception was modulated by ventromedial prefrontal cortex and ventral striatum. These findings indicate that effort perception is a complex phenomenon reflecting brain activity within areas involved in motor, executive and valuation processes. Significance StatementThis study advances our understanding of the neural mechanisms underlying task performance under pain and increased effort perception. Brain activity was measured during a visuomotor force-matching task performed in the presence or absence of pain. By contrasting task-related activity between painful and non-painful conditions, we identified regions associated with cognitive control and pain modulation involved in preserving task performance under pain. By correlating activity in regions of interest with ratings of perceived effort, we demonstrated the involvement of the supplementary motor area and midcingulate cortex in effort perception. These findings suggest that additional neural resources are recruited to maintain performance during pain and that the supplementary motor area and midcingulate cortex contribute to heightening the effort experienced.

neuroscience↗

bioRxiv2026

Mental fatigue impairs cycling endurance performance and perception of effort, but not muscle activation

Mental fatigue is induced by prolonged engagement in cognitively demanding tasks and impairs endurance performance. The neuropsychophysiological mechanisms underlying this decreased performance remain unclear, with suggestion that mental fatigue may disrupt motor command and consequently muscle activation. We aimed to test this hypothesis in a repeated cross-over design study in which 18 participants completed two experimental sessions involving a time-to-task failure cycling test at 80% of peak power output. Each cycling task was preceded by 1h of a prolonged Stroop task (Stroop condition) or a neutral control task (Control condition). Mental fatigue was assessed using a visual analog scale anchored with "not fatigued at all" and "extremely fatigued. Perception of effort and surface electromyography from ten lower-limb muscles of the right leg were recorded at regular intervals during cycling. Mental fatigue was higher in the Stroop compared to the Control condition (p = .002). Endurance cycling time was shorter in the Stroop than in the Control condition (887 {+/-} 284 s vs. 999 {+/-} 379 s, respectively; -111 {+/-} 160 s, p = .009). No significant differences in electromyography parameters were observed between Stroop and Control conditions, for any muscle (p > .05). Perception of effort was higher in the Stroop condition from the onset of the cycling task (p = .006), and the rate of increase in perception of effort was significantly higher in the Stroop than Control condition (p = .031). Our findings do not support the hypothesis that mental fatigue alters motor control or increases central motor command, as no changes in muscle activation were detected. Conversely, our results reinforce the notion that prolonged cognitive engagement impairs endurance performance primarily through an increased perception of effort. Future research should consider combining surface electromyography with more sensitive neurophysiological techniques to investigate potential subtle changes in motor drive during dynamic, whole-body tasks under mental fatigue.

physiology↗

bioRxiv2026

Maintaining performance under pain is effortful: experimental and computational evidence

Pain creates a competing demand on attention, though its impact on performance remains debated. Motivational intensity theory predicts that resource reallocation can preserve output until motivational or capacity limits are reached. Forty adults took part in two preregistered experiments. They completed parallel cognitive (choice reaction, n=20) and motor (isometric hand grip, n=20) tasks at three difficulty levels while receiving warm, low, or high pain heat stimulation on the opposite forearm. Across both domains, participants maintained performance despite painful stimulation. This preservation, however, relied on increased effort mobilization: perceived effort rose with pain intensity, while pain perception decreased during motor and cognitive task execution. Trial wise computational modelling revealed that perceived effort was better predicted by subjective pain experience than by stimulus temperature, supporting a compensatory regulatory mechanism. Thus, maintained performance under pain reflects active resource allocation via effort, generalizable across cognitive and motor domains, but achieved at the cost of increased perceived effort.

neuroscience↗

bioRxiv2026

The central motor command, but not the muscle afferent feedback, is necessary to perceive effort

Two theoretical models are proposed on the signal processed by the brain to generate the perception of effort (PE): the corollary discharge model and the afferent feedback model. To test the validity of these models, we used electromyostimulation to manipulate the magnitude of the central motor command during voluntary (high motor command), evoked (no motor command) and combined (low motor command) contractions at similar torque outputs. As electromyostimulation evokes sensory volleys to the central nervous system, it was used to evoke muscle contractions and to stimulate afferent feedback. We hypothesized that PE would reflect the magnitude of the central motor command and that evoked muscle contractions in the absence of central motor command would not elicit any PE. Twenty participants (n=10 experienced and n=10 novice with electromyostimulation) volunteered in this study. Participants reported their PE after isometric (10% and 20% MVC) and dynamic (5% and 20% MVC) voluntary, evoked, and combined contractions. For the same torque, participants reported no PE during evoked contractions, but all reported PE during voluntary contractions. Experienced but not novice participants reported lower PE during the combined than during voluntary contractions. This study questions the validity of the afferent feedback model and highlights the key role of motor command-related signals in PE generation. However, results from the novice participants during the combined contractions suggest that other factors such as inhibitory control may affect PE. Future studies should investigate the relationship between the central motor command and PE during physical tasks at various levels of complexity.

neuroscience↗

bioRxiv2025

Aerobic Exercise Intensity: A Dose-Response Effect on Motor Adaptation and Learning

Acute aerobic exercise (AEX) can enhance motor learning. While AEX intensity likely plays a key role, there is mixed evidence for AEX-enhanced motor skill acquisition and learning across a spectrum of exercise intensities. This may stem, in part, from inconsistent AEX parameters (i.e., intensity, structure, and duration) employed within and across studies. Additionally, evidence suggests that AEX can enhance a specific form of motor learning, namely motor adaptation. Moderate- and high-intensity AEX can increase motor adaptation, but evidence remains limited and inconsistent. Hence, the impact of AEX intensity on motor adaptation remains unclear. Here, we investigated the influence of AEX intensity on motor adaptation, while controlling for AEX structure and duration. Eighty young adults were assigned to four cycling AEX/Rest groups (n=20/group): 20 min of light (LIIT), moderate (MIIT), or high (HIIT) intensity interval training, or Rest (control). AEX consisted of four 3-min cycling intervals (LIIT, 35% heart rate reserve [HRR]; MIIT, 55%HRR; HIIT, 80%HRR) and 2-min active recovery (25%HRR). Participants practiced a visuomotor rotation task immediately after AEX/Rest (adaptation) and at a no-AEX 24 h retention test (motor learning). We found that: (1) all AEX intensities enhanced motor learning compared to Rest, and (2) HIIT enhanced motor adaptation and learning to the greatest extent, followed by MIIT then LIIT. This is the first study to demonstrate a dose-response effect of AEX intensity on motor adaptation and learning. Our results highlight the importance of considering intensity when prescribing AEX in sports and clinical contexts to promote motor learning.

neuroscience↗

bioRxiv2025

Effects of experimentally induced fatigue on motor learning: A scoping review

The literature on the effect of fatigue on motor learning is limited and marked by inconsistent findings. This scoping review aimed to explore the available knowledge on the effects of fatigue induced by physical and cognitive exertion on motor learning, and to compile and understand how it is studied. A comprehensive search strategy using relevant index terms and keywords was conducted across MEDLINE, EMBASE, SPORTDiscus, Web of Science, PsycINFO, CINAHL, ERIC, and Dissertations & Theses Global. Twenty-five studies met the inclusion criteria. The findings revealed considerable inconsistencies in how fatigue and motor learning were defined and measured. None of the studies examined the effect of fatigue induced by combined physical and cognitive exertion, and only 7 studies investigated fatigue induced by cognitive exertion. Acuity tasks were the most frequently used to assess motor learning, employed in 14 studies. Notably, all participants were between 16.5 and 31 years of age, and reporting of key demographic and physiological characteristics such as sex, gender, physical activity level, and body mass index was inconsistent or absent. This review highlights the need for comprehensive definitions of both fatigue and motor learning to improve consistency and reproducibility across studies. Given the limited research on the effects of fatigue induced by cognitive and combined physical and cognitive exertion, future studies should prioritize using these experimental manipulations. Also, future studies should diversify the motor learning tasks used in research to allow both direct and conceptual replication. Additionally, broader age ranges and comprehensive participant profiling should be prioritized.

neuroscience↗

bioRxiv2025

Physical exercise and motor learning: A scoping review

Physical exercise can enhance motor learning by inducing neurophysiological changes that facilitate this process. This preregistered scoping review aimed to map current knowledge on the effects of physical exercise on motor learning. Experimental studies and review articles examining any form of physical exercise in healthy or clinical populations were included, with outcomes assessing motor skill acquisition and/or retention. A systematic search across eight databases (e.g., MEDLINE, EMBASE, PsychINFO) identified 66 sources, including 62 experimental studies and 4 reviews. Two researchers independently reviewed articles and extracted data using a pretested data extraction table; disagreements at the study selection or data extraction stages were resolved through discussion with a third researcher. Most studies involved healthy populations (83%), with clinical populations underrepresented (17%). Aerobic exercise was most commonly investigated, particularly lower-limb cycling (73%), while resistance exercise was rarely examined (0.6%). Exercise intensity was predominantly high, although 6% of studies reported intensity not reflecting the prescribed method. Motor learning outcomes varied: 55% assessed both skill acquisition and retention, while 45% relied on retention tests alone at short-term or delayed time points, or both. Infrequent use of long-term retention tests limits understanding of lasting effects. Overall, this review highlights gaps in the literature, including the underrepresentation of clinical populations, inconsistent reporting of exercise intensity, scarce research on resistance exercise, and limited assessment of long-term retention, which may affect interpretation of exercises impact on motor learning. HighlightsO_LIClinical populations were underrepresented in the exercise and motor learning field. C_LIO_LIHigh-intensity lower-limb cycling was the most common exercise studied. C_LIO_LIResistance exercise was underrepresented in the field. C_LIO_LIAccurate prescription of exercise intensity is essential to ensure reliable results. C_LIO_LIFuture research should more frequently use longer-term retention tests. C_LI

neuroscience↗

bioRxiv2025

Eccentric cycling enhances primary motor cortex excitability

Acute aerobic exercise (AAE) can modulate primary motor cortex (M1) excitability. To date, studies evaluating its effects have focused almost exclusively on concentric cycling. Critically, we found that eccentric AAE enhances motor learning more than concentric AAE, possibly explained by enhanced frontal-parietal brain activation during eccentric cycling. Yet, M1 excitability mechanisms underlying this eccentric AAE-enhanced motor learning remain unknown. Thus, this study aimed to evaluate the effect of eccentric cycling AAE on M1 excitability using transcranial magnetic stimulation (TMS). Thirty adults performed three 20 min-conditions: i) eccentric cycling AAE, ii) concentric cycling AAE, and iii) rest. Cycling AAE was carried out at a workload corresponding to 70% of peak heart rate (%HRpeak) measured during concentric incremental cycling exercise. TMS assessments were conducted before (Pre), immediately (Post0) and 20 minutes after (Post20) AAE/rest to evaluate changes in corticospinal excitability (CSE) and short-interval intracortical inhibition (SICI). Overall, we found CSE increased and intracortical inhibition (SICI) was reduced at Post20 to a comparable extent following eccentric and concentric cycling AAE compared to rest. Also, %HRpeak, muscle pain and perceived effort were lower during eccentric cycling AAE compared to concentric cycling AAE. Our results showed that eccentric cycling impacted M1 excitability change to a comparable degree as concentric cycling, while requiring less cardiovascular response, eliciting less muscle pain and lower perceived effort. Taken together, our results suggest that eccentric cycling AAE may be a valuable intervention to modulate M1 excitability for populations with limited cardiovascular capacity and may have potential implications in clinical and sports-related contexts.

neuroscience↗

bioRxiv2025

Eccentric cycling improves motor learning more than concentric cycling

An acute bout of aerobic exercise (AAE) performed before practicing a motor task can enhance skill acquisition and motor learning. To date, research on the effects of AAE on motor learning has focused exclusively on concentric cycling, leaving the impact of eccentric cycling unexplored. Unlike concentric cycling, eccentric cycling involves muscle lengthening while resisting the reverse movement of the pedals and is characterized by greater force production with lower cardiovascular and metabolic cost. Regarding neuroplasticity changes, eccentric contractions induced a prolonged decrease in intracortical inhibition compared to concentric contractions. Eccentric cycling AAE also increases activation in cognitive-related regions. Given the involvement of these regions and motor cortex excitability in motor learning, we hypothesized that eccentric cycling AAE would enhance motor learning to a greater extent than concentric AAE. A total of 60 young healthy individuals were allocated to one of three groups that performed 20 min of: i) eccentric cycling; ii) concentric cycling; or iii) seated rest. Both cycling AAE conditions were performed at a power equivalent to 70% peak heart rate (i.e., moderate intensity). A continuous tracking task was used to assess motor skill acquisition (immediately after the intervention) and motor learning (48 h retention test). For both acquisition and retention, the eccentric group outperformed both the concentric and rest groups, while the concentric group also showed a better performance compared to the rest group at retention. Thus, we demonstrated that eccentric cycling AAE enhances motor learning to a greater extent than concentric cycling AAE, while also confirming previous work that showed enhanced motor learning following concentric cycling AAE compared to rest. Our findings suggest that eccentric cycling AAE may have important implications for exercise protocols prescribed in sports-related and clinical contexts. HighlightsO_LIEccentric cycling enhanced motor learning to a greater extent than concentric cycling C_LIO_LIEccentric and concentric cycling enhanced motor learning more than rest C_LIO_LIEnhanced skill acquisition occurred after eccentric cycling, along with lower heart rate response and perceived effort. C_LIO_LIEccentric cycling may have important implications in sports-related and clinical contexts C_LI

neuroscience↗

bioRxiv2025

Motor cortical circuits are uniquely impacted by different exercise intensities

Acute aerobic exercise (AEX) can enhance motor learning and promote neuroplasticity. However, the effect of AEX intensity on primary motor cortex (M1) excitability has not been systematically examined. Hence, the dose-response relationship between AEX intensity and M1 excitability modulation remains unclear. This study investigated the impact of AEX intensity on distinct M1 circuits using transcranial magnetic stimulation (TMS). Thirty right-handed adults underwent four experimental sessions: rest (control), light (LIIT), moderate (MIIT), and high-intensity interval training (HIIT) AEX. AEX intensity was prescribed with the heart rate reserve (HRR) method, and the interval cycling sessions consisted of alternating between 3 min at the target intensity (LIIT: 35% HRR; MIIT: 55% HRR; HIIT: 80% HRR) and 2 min of active recovery (25% HRR) for 20 min total. We performed TMS measures before (Pre), immediately post (Post0), and 20 min post (Post20) AEX/rest to assess modulation of corticospinal excitability and GABAergic inhibition as measured by short interval-intracortical inhibition (SICI). This study found that: (1) HIIT and MIIT increased corticospinal excitability, with HIIT eliciting a sustained increase; and (2) all AEX intensities (LIIT, MIIT and HIIT) decreased SICI, with the greatest sustained reduction following MIIT. Also, there was a greater reduction in GABAergic inhibition when measured with anterior-posterior than posterior-anterior TMS current following MIIT. Collectively, our results demonstrate the impact of HIIT and MIIT to enhance corticospinal excitability and reduce GABAergic inhibition in M1. This study provides evidence for a dose-response effect of AEX intensity on the modulation of distinct motor cortical circuits. KEY POINTS SUMMARYO_LIAcute aerobic exercise (AEX) is known to modulate primary motor cortex (M1) excitability, but the effect of AEX intensity is unclear. C_LIO_LIThis study examined the impact of light-, moderate-, and high-intensity interval training (LIIT, MIIT, HIIT) AEX and rest (non-AEX, control) on distinct M1 cortical circuits using transcranial magnetic stimulation (TMS). C_LIO_LIHIIT induced a sustained increase in M1 output excitability, MIIT induced a transient increase, and LIIT showed no effect. C_LIO_LIAll exercise intensities (LIIT, MIIT and HIIT) decreased GABAergic inhibition, as measured by short-interval intracortical inhibition (SICI), with MIIT showing a sustained decrease. C_LIO_LISICI measured with an anterior-to-posterior TMS current demonstrated greater GABAergic disinhibition compared to posterior-to-anterior TMS current following MIIT. C_LIO_LIThis study demonstrates a nuanced dose-response impact of AEX intensity on distinct M1 cortical circuits. C_LI

neuroscience↗

bioRxiv2022

Eccentric cycling involves greater mental demand and cortical activation of the frontoparietal network

Eccentric, compared to concentric exercise, is proposed to involve different neuro-motor processing strategies and a higher level of mental demand. This study compared eccentric and concentric cycling at matched perceived effort and torque for the mental demand and related-cortical activation patterns. Nineteen men (30 {+/-} 6 yrs) performed four different 5-min cycling conditions at 30 RPM on a semi-recumbent isokinetic cycle ergometer: 1) concentric at a moderate perceived effort (23 on the CR100(R) scale) without torque feedback; 2) concentric and 3) eccentric at the same average torque produced in the first condition; and 4) eccentric at the same moderate perceived effort than the first concentric condition. The conditions 2-4 were randomised. After each condition, mental demand was monitored using the NASA Task Load Index scale. Changes in oxy-(O2Hb) and deoxy-(HHb) haemoglobin during exercise were meas-ured over both prefrontal cortices and the right parietal lobe from a 15-probe layout using a continuous-wave NIRS system. Mental demand was significantly higher during eccentric compared to concentric cycling (+52%, p = .012) and when the exercise intensity was fixed by the torque rather than the perceived effort (+70%, p .001). For both torque- or perceived effort-matched exercises, O2Hb increased significantly (p < .001) in the left and right prefrontal cortices, and right parietal lobe, and HHb decreased in the left, and right, prefrontal cortices during eccentric compared to concentric cycling. This study supports that acute eccentric cycling, compared to concentric cycling, involves a higher mental demand and frontoparietal network activation.

physiology↗

bioRxiv2021

Pharmacological blockade of muscle afferents and perception of effort: a systematic review with meta-analysis

BackgroundThe perception of effort (PE) provides information on task difficulty and influences physical exercise regulation and human behavior. This perception differs from other-exercise related perceptions such as pain. There is no consensus on the role of group III-IV muscle afferents as a signal processed by the brain to generate PE. ObjectiveThe aim of this meta-analysis was to investigate the effect of pharmacologically blocking muscle afferents on the PE. MethodsSix databases were searched to identify studies measuring the ratings of perceived effort (RPE) during physical exercise, with and without pharmacological blockade of muscle afferents. Articles were coded based on the operational measurement used to distinguish studies in which PE was assessed specifically (effort dissociated) or as a composite experience including other exercise-related perceptions (effort not dissociated). Articles that did not provide enough information for coding were assigned to the unclear group. ResultsThe effort dissociated group (n=6) demonstrated a slight RPE increase with reduced muscle afferents feedback (standard mean change raw (SMCR), 0.39; 95%CI, 0.13 to 0.64). The group effort not dissociated (n=2) did not reveal conclusive results (SMCR, -0.29; 95%CI, -2.39 to 1.8). The group unclear (n=8) revealed a slight RPE decrease with reduced muscle afferents feedback (SMCR, -0.27; 95%CI, -0.50 to -0.04). ConclusionsThe heterogeneity in results between groups reveals that the inclusion of perceptions other than effort in its rating influences the RPE scores reported by the participants. The absence of decreased RPE in the effort dissociated group suggests that muscle afferents feedback is not a sensory signal of PE. Key pointsO_LITo date, there is no consensus on the neurophysiological signal processed by the brain to generate the perception of effort. C_LIO_LIFollowing a systematic search in six databases, this meta-analysis suggests that reducing afferent feedback from the working muscles via epidural anesthesia does not reduce perception of effort. C_LIO_LIThis systematic review suggests that afferent feedback from the working muscles is not the neurophysiological signal processed by the brain to generate the perception of effort. C_LI

neuroscience↗

bioRxiv2021

Perception of effort during an isometric contraction is influenced by prior muscle lengthening or shortening

PurposeFollowing a shortening or lengthening muscle contraction, the torque produced in the isometric steady state is distinctly lower (residual torque depression; rTD) or higher (residual torque enhancement; rTE), respectively, compared to a purely isometric contraction at the same final muscle length and level of activation. This is referred to as the history dependence of force. When matching a given torque level, there is greater muscle activation (electromyography; EMG) following shortening and less activation following lengthening. Owing to these differences in neuromuscular activation, it is unclear whether perception of effort is altered by the history dependence of force. MethodsExperiment 1 tested whether perception of effort differed between the rTD and rTE state when torque was matched. Experiment 2 tested whether perception of effort differed between the rTD and rTE state when EMG was matched. Finally, experiment 3 tested whether EMG differed between the rTD and rTE state when perception of effort was matched. ResultsWhen torque was matched, both EMG and perception of effort were higher in the rTD compared to rTE state. When EMG was matched, torque was lower in the rTD compared to rTE state while perception of effort did not differ between the two states. When perception of effort was matched, torque was lower in the rTD compared to rTE state and EMG did not differ between the two states. ConclusionThe combined results from these experiments indicate that the history dependence of force alters ones perception of effort, dependent on the level of motor command.

neuroscience↗