4 research outputs found
La cohérence intermusculaire (IMC) révèle que les images émotionnelles affectives modulent les mécanismes de contrôle neuronal lors de l'initiation des mouvements de pointage des bras
No full textSeveral studies in psychology provided compelling evidence that emotions significantly impact motor control. Yet, these evidences mostly rely on behavioral investigations, whereas the underlying neurophysiological processes remain poorly understood. Using a classical paradigm in motor control, we tested the impact of affective pictures associated with positive, negative or neutral valence on the kinematics and patterns of muscle activations of arm pointing movements performed from a standing position. The hand reaction and movement times were measured and electromyography (EMG) was used to measure the activities from 10 arm, leg and trunk muscles that are involved in the postural maintenance and arm displacement in pointing movements. Intermuscular coherence (IMC) between pairs of muscles was computed to measure changes in patterns of muscle activations related to the emotional stimuli. The hand movement time increased when an emotional picture perceived as unpleasant was presented as compared to when the emotional picture was perceived as pleasant. When an unpleasant emotional picture was presented, beta (β, 15-35 Hz) and gamma (γ, 35-60 Hz) IMC decreased in the recorded pairs of postural muscles during the initiation of pointing movements.Moreover, a linear relationship between the magnitude of the intermuscular coherence in the pairs of posturo-focal muscles and the hand movement time was found in the unpleasant scenarios. These findings demonstrate that emotional stimuli can significantly affect the content of the motor command sent by the central nervous system to muscles when performing voluntary goal-directed movements
Alpha, Sensorimotor Rhythms and Beta Event-Related Desynchronisation during Kinesthetic Motor Imagery of experts and novices
No full textInternational audienceKinesthetic Motor Imagery (KMI), consists in imagining movements’ associated sensations such as muscular contractions. It is widely used by athletes as it can increase motor skills [1-4]. Whereas movement execution produces physiological outputs, used as feedback to correct one’s practice, KMI does not allow athletes to objectify their strategies. However, KMI is associated with an event-related desynchronisation (ERD) of sensorimotor rhythms (SMRs) [5] making BCIs adapted to provide real time feedback. Through a better guidance of athletes, sport performance and brain modulation ability may be optimised [6-8]. Many KMI-BCI protocols reward maximum SMR-ERD [9], considering growing expertise will be associated with a higher desynchronisation of neurons in the sensorimotor cortices [10]. However, the neural efficiency hypothesis [11, 12] suggests we might need to reward different neuromarkers. To contribute to the debate, we investigated neural correlates of expertise, in sport expertise and perceived KMI expertise. We hypothesised that experts’ SMR-ERDs would differ from novices’ and suggested groups would have different solicitations of Alpha, SMRs and Beta. Indeed, as a reflection of temporal stability, experts would have specific modulations in comparison to novices’ that would be more widespread across frequency bands. Thus, we planned an experimental design with "Expertise" (basketball-experts, novices; between groups) and "Frequency band" (Alpha, SMR, Beta; within groups) as factors. Self-reported KMI ability allowed us to observe potential differences between groups and if so, add it as a covariable. Our results show that experts reported higher perceived KMI abilities than novices. In addition, ANOVA revealed a main effect of the group and frequency band, as well as a tendency towards a main effect of the interaction group x frequency band. Group effect was only weakly mediated by perceived KMI ability, and seemed to be mainly driven by sport expertise
Alpha, Sensorimotor Rhythms and Beta Event-Related Desynchronisation during Kinesthetic Motor Imagery of experts and novices
No full textInternational audienceKinesthetic Motor Imagery (KMI), consists in imagining movements’ associated sensations such as muscular contractions. It is widely used by athletes as it can increase motor skills [1-4]. Whereas movement execution produces physiological outputs, used as feedback to correct one’s practice, KMI does not allow athletes to objectify their strategies. However, KMI is associated with an event-related desynchronisation (ERD) of sensorimotor rhythms (SMRs) [5] making BCIs adapted to provide real time feedback. Through a better guidance of athletes, sport performance and brain modulation ability may be optimised [6-8]. Many KMI-BCI protocols reward maximum SMR-ERD [9], considering growing expertise will be associated with a higher desynchronisation of neurons in the sensorimotor cortices [10]. However, the neural efficiency hypothesis [11, 12] suggests we might need to reward different neuromarkers. To contribute to the debate, we investigated neural correlates of expertise, in sport expertise and perceived KMI expertise. We hypothesised that experts’ SMR-ERDs would differ from novices’ and suggested groups would have different solicitations of Alpha, SMRs and Beta. Indeed, as a reflection of temporal stability, experts would have specific modulations in comparison to novices’ that would be more widespread across frequency bands. Thus, we planned an experimental design with "Expertise" (basketball-experts, novices; between groups) and "Frequency band" (Alpha, SMR, Beta; within groups) as factors. Self-reported KMI ability allowed us to observe potential differences between groups and if so, add it as a covariable. Our results show that experts reported higher perceived KMI abilities than novices. In addition, ANOVA revealed a main effect of the group and frequency band, as well as a tendency towards a main effect of the interaction group x frequency band. Group effect was only weakly mediated by perceived KMI ability, and seemed to be mainly driven by sport expertise
