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International audience; Virtual and Augmented Reality Environments have long been seen as having strong potential for educational applications. However, research showing actual evidences of their benefits is sparse. Indeed , some recent studies point to unnoticeable benefits, or even a detrimental effect due to an increase of cognitive demand for the students when using these environments. In this work, we question if a clear benefit of AR and VR can be robustly measured for a specific education-related task: learning a 3D object. We ran a controlled study in which we compared three interaction techniques. Two techniques are VR-and AR-based; they offer a High Fidelity (HF) virtual reproduction of observing and manipulating physical objects. The third technique is based on a multi-touch tablet and was used as a baseline. We selected a task of 3D object learning as one potentially benefitting from the HF reproduction of object manipulation. The experiment results indicate that VR and AR HF techniques can have a substantial benefit for education as the object was recognized more than 27% faster when learnt using the HF techniques than when using the tablet.

BACKGROUND There is now ample evidence that motor imagery contributes to enhance motor learning and promote motor recovery in patients with motor disorders. Whether motor imagery practice is likely to facilitate mobility in patients suffering from knee osteoarthritis, at 6-months after total knee arthroplasty, remains unknown. AIM This trial was designed to evaluate the therapeutic effectiveness of implementing motor imagery into the classical course of physical therapy at 6-months after total knee arthroplasty. DESIGN Randomized controlled trial. POPULATION Twenty-four patients with unilateral total knee arthroplasty were assigned to a motor imagery or control group in a test-retest procedure, following a rehabilitation program as outpatients. METHODS During both the pre- and post-test, a set of strength and functional mobility measures were assessed: quadriceps strength, peak knee flexion during the swing phase, performance at the timed up and go test, stair climbing test, and 6-minute walk test, and finally Oxford knee score. In addition to a common physical therapy program, the motor imagery group practiced additional motor imagery exercises, while participants of the control group were subjected to a period of neutral activities for an equivalent amount of time. RESULTS Data provided evidence that motor imagery enhanced the quadriceps muscle strength of the operated knee (F (1, 22)=10.36, P=0.003), improved the peak knee flexion during the swing phase (F (1, 22)=31.52, P

International audience; Previous studies provided evidence of a relationship between mental rotation (MR) and motor processes in children and adults. However, there is no direct evidence that MR ability is a reliable predictor of success for motor performance. After completion of a MR test, the motor performance of 7- to 8-year-old and 11- to 12-year-old children was measured along a steeple chase and an equivalent straight distance sprint. The chase involved several motor actions requiring, among different competencies, spatial abilities such as performing a forward roll, jumping, crawling, turning, and changing directions. Data revealed that the time taken to complete the chase was influenced by speed and sex, but also by the individual MR ability. Based on these findings, we assume that MR and motor performance may share similar subprocesses.

It is commonly believed that during mental rotation of body parts, participants tend to imagine their own body part moving toward the stimulus, thus using an egocentric strategy. Several studies have also shown that the mental rotation of hands is affected by the actual hand position, especially if the hand is kept in an awkward position. However, this hand posture effect, as well as the use of an egocentric strategy during mental rotation of body parts, is not systematic. Several experiments have demonstrated that manipulating the stimulus features or the paradigm could induce a shift to visual and allocentric strategies. Here, we studied the effects of hand posture and biomechanical constraints on one-hand mental rotation (laterality judgment task), two-hand mental rotation (same-different judgment task), and mental rotation of one or two alphanumeric symbols (control tasks). Effects of posture and biomechanical constraints were observed solely for the laterality judgment task. Response times in the same-different hand mental rotation items were influenced by the angular disparity between the stimuli. We interpreted our result as evidence of the use of different strategies for each task. Future research should focus on disentangling the exact subprocesses in which an egocentric strategy is used, in order to propose better tests for participants with motor impairments.

Background Reduced physiological arousal in response to breath-holding affects internal clock processes, leading swimmers to underestimate the time spent under apnea. We investigated whether reduced physiological arousal during static apnea was likely to affect the temporal organization of motor imagery (MI). Methods Fourteen inter-regional to national breath-holding athletes mentally and physically performed two 15 m swimming tasks of identical durations. They performed the two sequences in a counterbalanced order, the first while breathing normally using a scuba, the second under apnea. We assessed MI duration immediately after completion of the corresponding task. Athletes performed MI with and without holding breath. Results MI durations (26.1 s ± 8.22) were significantly shorter than actual durations (29.7 s ± 7.6) without holding breath. Apnea increased MI durations by 10% (± 5%). Heart rate decrease in response to breath-holding correlated with MI durations increase (p

Dans les protocoles experimentaux portant sur l’imagerie motrice, la question de l’evaluation effective du travail mental effectue par les participants demeure une question recurrente pour le chercheur. De meme, le praticien doit pouvoir disposer de methodes lui permettant d’evaluer la qualite de l’imagerie motrice, qu’il soit entraineur et l’utilise a l’amelioration de la performance ou clinicien et en prescrive la pratique pour favoriser le recouvrement des fonctions motrices. Si les evaluations subjectives, faites par les participants, et la passation de questionnaires restent des outils frequemment utilises, on dispose aussi d’indicateurs physiologiques centraux et peripheriques. La neuroimagerie identifie les correlats structuraux et fonctionnels de l’imagerie motrice, mais cette methodologie n’est pas ambulatoire et reste reservee aux protocoles de laboratoire. Les indicateurs peripheriques apportent des signes objectifs du travail mental dont il faut traiter les donnees pour pouvoir les exploiter afin d’evaluer la qualite de l’imagerie. L’objectif de cet article est de presenter les caracteristiques et limites de ces familles methodologiques.

International audience; Temporal congruence between motor imagery and motor performance was evaluated in 30 elementary school children (7 and 8-year-olds) and 61 middle school children (11 and 12-year-olds), using the " Harre's Chase " obstacle-course [Harre, D. (1976). Trainingslehre. Berlin: Sportverlag]. It is made of successive elementary actions including running, rolling forward, changing direction, jumping and crawling. The children were requested to perform the obstacle-course both actually and mentally. Results showed that motor imagery duration was closer to that of actual execution in the middle school children group, as compared to elementary school children. We also found a gender difference, boys being more able than girls to reach the temporal congruency between imagined and physical times. Developmental factors, as well as gender differences in socio-cognitive traits, are discussed as the main factors explaining the development of the isochrony between actual and imagined movements.

International audience; Background: Mental rotation (MR) is improved through practice and high MR ability is correlated to success in anatomy learning. Purposes: We investigated the effects of improving the MR ability on the Vandenberg and Kuse MR test performance and the consequences on learning functional human anatomy. Methods: Forty-eight students were assigned into three groups: MR group (16 students attending functional anatomy course and MR training), anatomy group (16 students attending the same functional anatomy course), and the control group (n = 16). Instead of MR training, the latter 2 groups were engaged in physical activities for an equivalent time, and the control group did not attend anatomy course. Results: MR group performed better than the two others in the MR test and better than the anatomy group in the anatomy test. Conclusions: The MR training sessions were found to improve MR test performance and were further transferred to anatomy learning.