RICHIE: A Step-by-step Navigation Widget to Enhance Broad Hierarchy Exploration on Handheld Tactile Devices

International audienceExploring large hierarchies is still a challenging task, especially for handheld tactile devices, due to the lack of visualization space and finger's occlusion. In this paper, we propose the RICHIE (Radial In-Cremental HIerarchy Exploration) tool, a new radial widget that allows step-by-step navigation through large hierarchies. We designed it to fit handheld tactile requirements such as target reaching and space optimization. Depth exploration is made by shifting two levels of hierarchy at the same time, for reducing the screen occupation. This widget was implemented in order to adapt a Command and Control (C2) system to mobile tactile devices, as these systems require the on-screen presence of an important unit's hierarchy (the ORder of BATtle). Nevertheless, we are convinced that RICHIE could be used on several systems that require hierarchical data exploration, such as phylogenetic trees or file browsing

Contextual Interfaces for Operator-Simulator Interaction

International audienceWe present the results of a study on the role of context in the mental representation that operators have of their task realization. This work is part of the ANR TACTIC project, which aims at proposing a migration of a simulator's interface from PC (" click-simulation ") to tactile devices (" finger-simulation ")

Delayed postural control during self-generated perturbations in the frail older adults

International audiencePurpose: The aim of this study was to investigate the coordination between posture and movement in pathological aging (frailty) in comparison with normal aging, with the hypothesis that in pathological aging, postural control evolves towards a more reactive mode for which the perturbation induced by the movement is not anticipated and leads to delayed and late postural adjustments. Methods: Elderly subjects performed rapid focal arm-raising movements towards a target, from an upright standing position in two stimuli conditions: simple reaction time and choice reaction time (CRT). Hand and center of pressure (CoP) kinematics were compared between a control group and a frail group of the same age. Results: In frail individuals, the entire movement was impaired and slowed down. In addition, postural adjustments that classically precede and accompany the focal arm movement were delayed and reduced, especially in the CRT condition in which the motor prediction is more limited. Finally, a correlation between the time to CoP maximal velocity and the timed up-and-go score was observed. Conclusion: In these patients, it was concluded that the control of the CoP displacement evolved from a proactive mode in which the perturbation associated with the arm movement is anticipated toward a more reactive mode in which the perturbation is compensated by late and delayed adjustments

Using contextual factors to elicit placebo and nocebo effects: An online survey of healthcare providers' practice

Contextual factor use by healthcare professionals has been studied mainly among nurses and physiotherapists. Preliminary results show that healthcare professionals use contextual factors without specifically labelling them as such. The main objective of this study was to evaluate knowledge and explore voluntary contextual factor use among various healthcare professions. The results aim to facilitate hypothesis-generation, to better position further research to explain and characterise contextual factor use. We conducted a web-based questionnaire cross-sectional observational study on a non-probabilistic convenience sample. Face and content validity were tested through cognitive interviews. Data were analysed descriptively. The target population was the main healthcare profession, or final year students, defined by the French public health law. The countries of distribution of the questionnaire were the French-speaking European countries. Among our 1236 participants, use of contextual factors was widespread. Those relating to the therapeutic relationship (e.g., communication) and patient characteristics (e.g., past experiences) were reportedly the most used. Meanwhile, contextual factors related to the healthcare providers' characteristics and their own beliefs were reported as less used. Despite high variability, respondents suggested contextual effects contribute to approximately half of the overall effect in healthcare and were perceived as more effective on children and elderly adults. Conceptual variations that exist in the literature are also present in the way healthcare providers consider contextual effects. Interestingly, there seems to be common ground between how physiotherapists, nurses and physicians use different contextual factors. Finally, in the present study we also observed that while there are similarities across usage, there is lack of both an epistemological and ethical consensus among healthcare providers with respect to contextual factors

Postural adjustments and kinematic index finger features in frail older adults under different equilibrium constraints

Background: Anticipatory postural adjustments (APAs) are significantly affected by age and may represent restrictions on functional independence. Previous studies in young adults have already highlighted that changing postural stability (i.e., seated vs. upright posture) affects the motor planning and APAs. In frail older adults (FOAs), the effect of these different conditions of postural stability have not yet been established, and the present study aimed to disentangle this issue. Methods: Participants executed an arm-pointing task to reach a diode immediately after it turned on, under different conditions of stability (seated with and without foot support and in an upright posture). A kinematic profile of the index finger and postural electromyographic data were registered in their dominant-side leg muscles: Tibialis anterior, soleus, rectus femoris, and semitendinosus. Results: The main finding of this study was that the adopted posture and body stabilization in FOAs did not reflect differences in APAs or kinematic features. In addition, they did not present an optimal APA, since postural muscles are recruited simultaneously with the deltoid. Conclusion: Thus, FOAs seem to use a single non-optimal motor plan to assist with task performance and counterbalance perturbation forces in which they present similar APAs and do not modify their kinematics features under different equilibrium constraints

Enjeux et perspectives de l’accès direct en Masso-Kinésithérapie

International audienc

Functional assessment in older adults: Should we use timed up and go or gait speed test?

International audienceIn order to assess functional skills of older adults, both timed up and go (TUG) test and gait speed (GS) test are well validated concerning their predictive capacities. However, the question remains unclear which one of these tests represents better the whole physical performance of older adults. The aim of this study is to determine the more representative test, between TUG and GS, of the whole motor control quality. To study links between locomotion capacities and arm function, we measured, in a population of frail aged patients, the locomotion tests and the mean arm maximal velocity developed during a speed accuracy trade-off. This arm movement consisted in reaching the hand toward a target in a virtual game scene. We plotted the different couples of variables obtained on graphs, and calculate Pearson correlation coefficients between each couple. The Pearson correlation between GS and hand maximal velocity was significant (r = 0.495; p = 0.046). Interestingly, we found a non significant Pearson correlation between timed up and go score (TUG) and hand maximal velocity (r = -0.139; p = 0.243). Our results suggest that GS score is more representative of the whole motor ability of frail patients than the TUG. We propose that the relative complexity of the TUG motor sequence could be involved in this difference. For a few patients with motor automatisms deficiencies, this motor sequence complexity could leads to a dual task perturbation. In this way, we conclude that GS should be preferred over the TUG with older adults. (C) 2014 Elsevier Ireland Ltd. All rights reserved

EquiMog : équilibre et motricité en gériatrie

International audienc