Facial expression overrules lumbopelvic kinematics for clinical judgements regarding low back pain intensity

Through real-time behavioral observation systems, pain behaviors are commonly used by clinicians to estimate pain intensity in patients with low back pain. However, little is known about how clinicians rely on pain-related behaviors to make their judgment. According to the Information Integration Theory (IIT) framework, this study aimed at investigating how clinicians value and integrate information from lumbopelvic kinematics (LK), a protective pain behavior, and facial expression intensity (FEI), a communicative pain behavior, to estimate pain in patients with chronic low back pain (cLBP). Methods. Twenty-one experienced clinicians and twenty-one novice clinicians were asked to estimate back pain intensity from a virtual character performing a trunk flexion-extension task. Results. Results revealed that both populations relied on facial expression and that only half of the participants in each group integrated FEI and LK to estimate cLBP intensity. Among participants who integrated the two pain behaviors, averaging rule predominated among others. Results showed that experienced clinicians relied equally on FEI and LK to estimate pain, whereas novice clinicians mostly relied on FEI. Discussion. The use of additive rule of integration does not appear to be systematic when assessing others’ pain. When assessing pain intensity, communicative and protective pain behaviors may have different relevance

Emotional modulation of perception of others’ motor action

L’être humain est un être social amené à comprendre les comportements moteurs d’autrui. Selon la littérature, nous disposons de mécanismes cognitifs spécifiques, d’une part à la perception d’un corps humain (qu’il soit statique ou en mouvement), et d’autre part à la perception des expressions faciales émotionnelles. Ce travail de thèse vise à comprendre dans quelle mesure l'émotion véhiculée par le visage d'une personne, peut moduler notre perception de son action motrice. Les résultats de l’étude 1 ont montré que l’estimation de l’équilibre statique d’autrui pouvait être modulée par l’expression faciale émotionnelle (de sourire ou de crispation) exprimée par celui-ci. L’étude 2, a porté sur l’estimation de l’effort physique développé par une personne uniquement à partir de son expression faciale de douleur. Les résultats ont montré que les participants, dans ce type de tâche, utilisent deux mécanismes perceptifs automatiques. Le premier, mis en évidence par mesure fonctionnelle, facilite l’estimation de l’intensité de douleur à l’effort ressentie par autrui. Le second, démontré par la mesure d’un biais de mémorisation, entraîne une anticipation automatique de la suite de l’évolution de l’expression faciale de douleur à l’effort présentée. L’étude 3 a montré que l’estimation de l’effort physique développé par une personne atteinte de paraplégie réalisant un mouvement de transfert, est modulée par deux comportements de douleur (l’auto-protection et l’expression faciale de douleur). Toutefois, cette modulation diffère selon la familiarité des participants avec le monde médical et la paraplégie. En conclusion, ce travail de recherche propose que la modulation émotionnelle de la perception de l’action motrice d’autrui est en premier lieu sous-tendue par un processus automatique et implicite de contagion émotionnelle (bottom-up). Toutefois, cette dernière peut être inhibée par un processus explicite (top-down) qui dépendrait d’une part du type d’inférence à effectuer sur autrui (estimer l’équilibre postural ou l’effort physique développé), et d’autre part de la familiarité de l’observateur avec l’action motrice et les expressions faciales présentées.Understanding others’ motor behaviour is part and parcel of Humans’ social experience. According to scientific literature, we rely on specific mechanisms for perceiving human bodies (whether static or moving) on the one hand, and processing emotional facial expressions on the other hand. This thesis aims to understand to what extent the emotion conveyed by a person’s face can modulate one’s perception of her/his motor action. Results of study 1 showed that our estimation of an individual’s static equilibrium is modulated by the observed individual’s emotional facial expression (smiling or tensed). Study 2 focused on perceptual estimation of the physical effort developed by a person on the basis of his facial expression of pain alone. Results revealed that participants adopt two automatic perceptual mechanisms. The first, highlighted via functional measurement, facilitates estimating the intensity of effort pain felt by others. The second, evidenced by measuring memory bias, leads to an automatic anticipation of the subsequent changes in the intensity of pain-related facial expressions. Study 3 showed that the estimation of physical effort developed by a paraplegic individual performing a transfer movement is modulated by two pain behaviours (guarding and facial expression of pain). Interestingly, this modulation varies with participants’ familiarity with both the medical domain and paraplegia. The conclusion of this research suggests that the modulation of emotional perception related to others’ motor action is primarily subtended by an automatic (bottom-up) process and an implicit emotional contagion. However, the latter can be inhibited by an explicit (top-down) process which may depend on (1) the type of inference made on others (estimating postural balance or physical effort developed in others), and (2) the familiarity of the observer with motor action and facial expressions

Etude de l'ornementation des tissus mous de la sphère oro-labiale dans les tribus

RENNES1-BU Santé (352382103) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Modulation émotionnelle de la perception de l'action motrice d'autrui

L être humain est un être social amené à comprendre les comportements moteurs d autrui. Selon la littérature, nous disposons de mécanismes cognitifs spécifiques, d une part à la perception d un corps humain (qu il soit statique ou en mouvement), et d autre part à la perception des expressions faciales émotionnelles. Ce travail de thèse vise à comprendre dans quelle mesure l'émotion véhiculée par le visage d'une personne, peut moduler notre perception de son action motrice. Les résultats de l étude 1 ont montré que l estimation de l équilibre statique d autrui pouvait être modulée par l expression faciale émotionnelle (de sourire ou de crispation) exprimée par celui-ci. L étude 2, a porté sur l estimation de l effort physique développé par une personne uniquement à partir de son expression faciale de douleur. Les résultats ont montré que les participants, dans ce type de tâche, utilisent deux mécanismes perceptifs automatiques. Le premier, mis en évidence par mesure fonctionnelle, facilite l estimation de l intensité de douleur à l effort ressentie par autrui. Le second, démontré par la mesure d un biais de mémorisation, entraîne une anticipation automatique de la suite de l évolution de l expression faciale de douleur à l effort présentée. L étude 3 a montré que l estimation de l effort physique développé par une personne atteinte de paraplégie réalisant un mouvement de transfert, est modulée par deux comportements de douleur (l auto-protection et l expression faciale de douleur). Toutefois, cette modulation diffère selon la familiarité des participants avec le monde médical et la paraplégie. En conclusion, ce travail de recherche propose que la modulation émotionnelle de la perception de l action motrice d autrui est en premier lieu sous-tendue par un processus automatique et implicite de contagion émotionnelle (bottom-up). Toutefois, cette dernière peut être inhibée par un processus explicite (top-down) qui dépendrait d une part du type d inférence à effectuer sur autrui (estimer l équilibre postural ou l effort physique développé), et d autre part de la familiarité de l observateur avec l action motrice et les expressions faciales présentées.Understanding others motor behaviour is part and parcel of Humans social experience. According to scientific literature, we rely on specific mechanisms for perceiving human bodies (whether static or moving) on the one hand, and processing emotional facial expressions on the other hand. This thesis aims to understand to what extent the emotion conveyed by a person s face can modulate one s perception of her/his motor action. Results of study 1 showed that our estimation of an individual s static equilibrium is modulated by the observed individual s emotional facial expression (smiling or tensed). Study 2 focused on perceptual estimation of the physical effort developed by a person on the basis of his facial expression of pain alone. Results revealed that participants adopt two automatic perceptual mechanisms. The first, highlighted via functional measurement, facilitates estimating the intensity of effort pain felt by others. The second, evidenced by measuring memory bias, leads to an automatic anticipation of the subsequent changes in the intensity of pain-related facial expressions. Study 3 showed that the estimation of physical effort developed by a paraplegic individual performing a transfer movement is modulated by two pain behaviours (guarding and facial expression of pain). Interestingly, this modulation varies with participants familiarity with both the medical domain and paraplegia. The conclusion of this research suggests that the modulation of emotional perception related to others motor action is primarily subtended by an automatic (bottom-up) process and an implicit emotional contagion. However, the latter can be inhibited by an explicit (top-down) process which may depend on (1) the type of inference made on others (estimating postural balance or physical effort developed in others), and (2) the familiarity of the observer with motor action and facial expressions.PARIS11-SCD-Bib. électronique (914719901) / SudocSudocFranceF

Synthesis for the Kinematic Control of Identity in Sign Language

International audienceSign Language (SL) animations generated from motion capture (mocap) of real signers convey critical information about their identity. It has been suggested that this information is mostly carried by statistics of the movements kinematics. Manipulating these statistics in the generation of SL movements could allow controlling the identity of the signer, notably to preserve anonymity. This paper tests this hypothesis by presenting a novel synthesis algorithm that manipulates the identity-specific statistics of mocap recordings. The algorithm produced convincing new versions of French Sign Language discourses, which accurately modulated the identity prediction of a machine learning model. These results open up promising perspectives toward the automatic control of identity in the motion animation of virtual signers

Synthesis for the Kinematic Control of Identity in Sign Language

International audienceSign Language (SL) animations generated from motion capture (mocap) of real signers convey critical information about their identity. It has been suggested that this information is mostly carried by statistics of the movements kinematics. Manipulating these statistics in the generation of SL movements could allow controlling the identity of the signer, notably to preserve anonymity. This paper tests this hypothesis by presenting a novel synthesis algorithm that manipulates the identity-specific statistics of mocap recordings. The algorithm produced convincing new versions of French Sign Language discourses, which accurately modulated the identity prediction of a machine learning model. These results open up promising perspectives toward the automatic control of identity in the motion animation of virtual signers

Agency and social affordance shape visual perception

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Evaluating a Model of Pathological Affect based on Pedagogical Situations for a Virtual Patient

International audienceThe COPALZ model [3] is designed to simulate emotional disorders of a virtual agent representing a patient in a pedagogical scenario for training healthcare professionals. The identification of emotional and expressive pathologies may sometimes require an assessment over multiple interactions with trainees, as behaviors associated with emotional disorders are not systematically observed on patients' behavior in the early stages of the pathology. The aim of this article is to propose an evaluation method for this model, which, in the case of computational models of affects that generate nonverbal behaviors, requires a tailored approach. This task can be difficult as the correspondence between a pathology and observed behaviors is not systematic. Our method focuses on the pedagogical dimension and on the ability of the model to display pathological behaviors identified as relevant for training interactions. The results highlight the ability of the studied model to simulate multiple relevant pedagogical situations and adapt the virtual patient's behaviors to the evolution of the pathology and the patient's mood instability. This method gives interesting perspectives for the evaluation of virtual patients and computational models of affect. CCS Concepts • Human-centered computing → HCI design and evaluation methods

Quelles informations visuelles sont essentielles à la compréhension de la langue des signes ?

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