Couleurs et dyschromatopsies au cabinet dentaire

REIMS-BU Santé (514542104) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Feedback on the Use of Matb-Ii Task for Modeling of Cognitive Control Levels Through Psycho-Physiological Biosignals

Modeling individuals’ cognitive control levels in operational situations is a major challenge for safety in aeronautical industry. Standardized experimental tasks - as the Multi-Attribute Task Battery II (MATB-II) - are dedicated to such a challenge that can be faced using psycho-physiological biosignals. These biosignals are known to be sensitive to cognitive workload, performance, and expertise that are intricate features of MATB-II subtasks. Thus, it remained necessary to investigate whether these features could be set to ensure controlled experimental conditions. Two groups (15 experts in time-pressured decision making and 13 novices) completed 3 MATB-II sub-tasks (tracking, monitoring, and resource management tasks). Biosignals accounting for autonomic nervous system activity were measured continuously, as objective markers of cognition. Confrontation between performance data and (objective and subjective) cognitive markers reported contrasting perspectives regarding the exploitation of MATB-II as a pertinent tool to insure controlled experimental conditions in the context of cognitive control characterization

Changes in elbow joint’s musculo-articular mechanical properties do not alter reaching-related action-perception coupling

International audiencePurpose: Perception of action capabilities can be altered by changes in sensorimotor processes, as showed in previous works in populations dealing with regular and pathological sensorimotor deficits. Misestimating changes in performance ability could lead to risky behavior, injury, and/or reduced performance. However, the relationship between sensorimotor processes, the action-perception coupling, and the related anatomical structures is still a matter of debate. We investigated whether changes in the muscle-tendon system's mechanical properties experimentally induced by eccentric contractions could alter the action-perception coupling (APC) in a reaching-to-grasp task, in which the participants estimated the maximal distance they predicted that they would able to reach a glass.Methods: Based on their repartition, volunteers performed a conditioning session the first day: a series of isokinetic elbow extension in passive condition (control group, n = 11) or when performing elbow flexors eccentric contractions (eccentric group, n = 11). Performance estimates and actual performances in a reaching-to-grasp task were completed before, and immediately, 24 hours and 48 hours after the conditioning session. Alterations of musculo-articular mechanical properties were assessed through global joint stiffness (joint passive torque through load/unload cycles) and local stiffness (muscle elastography).Results: The results showed that the APC related to reaching-to-grasp performance was not impacted by post-exercise changes in mechanical properties of the musculo-articular system.Conclusion: These findings emphasize the central dimension of sensorimotor processing instead of peripheral structures to investigate the APC for an altered sensorimotor environment

Effects of total sleep deprivation on the perception of action capabilities

Changes in a subject's state have been shown to modulate the perceptual update of his or her action capabilities. In parallel, sleep deprivation impairs in cognitive functions. It involves common neural structures that support the perception of successfully achieving a motor task. Thus, the study investigated the effect of 24 h of sleep deprivation on the perception of action capabilities. Twenty-four healthy participants were randomly separated into two groups (control group vs. 24 h sleep deprivation group). Participants in the control group slept at home according to their habitual sleep-wake schedule. The 24-h sleep deprivation group stayed awake in the laboratory. Participants estimated the limit of their maximal height of stepping-over a bar before and after the sleep intervention. These estimations were compared to each participant's actual maximal stepping-over height. Physical performance (measured by maximal voluntary quadriceps contraction and repetitive vertical jumping tests) and perceptual inhibition tests (measured by choice reaction time tasks) were also performed for three sessions at three time points t (0), t (+12h), and t (+24h) with t (0) = 8:00 a.m. for all participants. Participants in the 24-h sleep deprivation group showed impairments in perceived over-stepping performance and impaired cognitive functioning (higher reaction time), while no changes were observed in actual performance in the over-stepping, voluntary quadriceps contraction, or jumping tasks. The cognitive processing of inputs that specify the estimated consequences of motor action is discussed as the main explanation for the inability to successfully update the perception of action capabilities after sleep deprivation

Impaired perception of reaching capabilities involves an atypical sensorimotor activity over the contralateral premotor area

International audienc

I can't reach it! Focus on theta sensorimotor rhythm toward a better understanding of impaired action-perception coupling

International audienceIt is known that anxiety (ANX) impairs action–perception coupling. This study tests whether this impairment could be associated with an alteration of the sensorimotor function. To this aim, the cortical activities underlying the sensorimotor function were recorded in twelve volunteers in a reach-to-grasp paradigm, in which the level of ANX and the position of a glass were manipulated. The experimental manipulation of the ANX-related somatosensory state was expected to prompt participants to underestimate their reaching-to-grasp capabilities while the sensorimotor-related oscillatory brain activities around the 6-Hz (θ) frequency over motor-related and parietal regions were expected to be modulated. We also investigated the oscillatory brain dynamics around the 11.5-Hz (fast-α) frequency as a neural hallmark of ANX manipulation induced by the breath-restriction. Results indeed showed that participants underestimated their reaching-to-grasp maximal performance. Concomittantly, θ-EEG synchronization over the motor cortex contralateral to the dominant hand was higher during glass presentation under breath-restriction condition (+20.1%; p < 0.05), and when the glass was perceived as non-reachable (+20.0%; p < 0.05). Fast-α-EEG desynchronization was reduced under breath-restriction (−37.7%; p < 0.05). The results confirm that ANX-related impairment of action–perception coupling co-modulates with theta-sensorimotor rhythm. This finding is discussed as an altered “readiness state” in the reaching-related cortical network, while individuals are anxious

Highly sensitive index of cardiac autonomic control based on time-varying respiration derived from ECG

International audienc

Sleep

Emotional reactivity to negative stimuli has been investigated in insomnia, but little is known about emotional reactivity to positive stimuli and its neural representation. We used 3 Tesla functional magnetic resonance imaging (fMRI) to determine neural reactivity during the presentation of standardized short, 10- to 40-seconds, humorous films in patients with insomnia (n = 20, 18 females, aged 27.7 +/- 8.6 years) and age-matched individuals without insomnia (n = 20, 19 females, aged 26.7 +/- 7.0 years) and assessed humor ratings through a visual analog scale. Seed-based functional connectivity was analyzed for the left and right amygdalas (lAMYG and rAMYG, respectively) networks: group-level mixed-effects analysis (FLAME; FMRIB Software Library [FSL]) was used to compare amygdala connectivity maps between groups. fMRI seed-based analysis of the amygdala revealed stronger neural reactivity in patients with insomnia than in controls in several brain network clusters within the reward brain network, without humor rating differences between groups (p = 0.6). For lAMYG connectivity, cluster maxima were in the left caudate (Z = 3.88), left putamen (Z = 3.79), and left anterior cingulate gyrus (Z = 4.11), whereas for rAMYG connectivity, cluster maxima were in the left caudate (Z = 4.05), right insula (Z = 3.83), and left anterior cingulate gyrus (Z = 4.29). Cluster maxima of the rAMYG network were correlated with hyperarousal scores in patients with insomnia only. The presentation of humorous films leads to increased brain activity in the neural reward network for patients with insomnia compared with controls, related to hyperarousal features in patients with insomnia, in the absence of humor rating group differences. These novel findings may benefit insomnia treatment interventions. The Sleepless Brain: Neuroimaging Support for a Differential Diagnosis of Insomnia (SOMNET). ClinicalTrials.gov identifier: NCT02821234; https://clinicaltrials.gov/ct2/show/NCT02821234.Bordeaux Region Aquitaine Initiative for Neuroscienc

Hum Factors

Objective: The study goal was to test whether induced stress during driving could be measured at the event level through electrodermal activity responses. Background: Stress measured in simulation scenarios could thus far show an overall change in the stress state, but not be well attributed to acute stressful events. Driving simulator scenarios that induce stress measurable at the event level in realistic situations are thus warranted. As such, acute stress reactions can be measured in the context of changing situational factors such as fatigue, substance abuse, or medical conditions. Method: Twelve healthy female participants drove the same route numerous times in a driving simulator, each time with different random traffic events occurring throughout. During one of the scenarios, unknown to the participants, 10 programmed neutral traffic events occurred, whereas in another scenario, at the same location, 10 stressful events occurred. Results: Electrodermal response results showed both effects of scenario type and of events. The amplitude of the electrodermal response was significantly correlated with subjective stress experience. Conclusion: We conclude that our developed ecological driving simulation scenarios can be used to induce and measure stress at the event level. Application: The developed simulator scenarios enable us to measure stress reactions in driving situations at the time when the event actually happens. With these scenarios, we can measure how situational factors, such as fatigue or substance abuse, can change immediate stress reactions when driving. We can further measure more specifically how induced driving stress can affect physical and mental functioning afterward.Bordeaux Region Aquitaine Initiative for NeurosciencePhénotypage humain et réalité virtuell