Viewing Pain and Happy Faces Elicited Similar Changes in Postural Body Sway

Abstract

Affective facial expressions are potent social cues that can induce relevant physiological changes, as well as behavioral dispositions in the observer. Previous studies have revealed that angry faces induced significant reductions in body sway as compared with neutral and happy faces, reflecting an avoidance behavioral tendency as freezing. The expression of pain is usually considered an unpleasant stimulus, but also a relevant cue for delivering effective care and social support. Nevertheless, there are few data about behavioral dispositions elicited by the observation of pain expressions in others. The aim of the present research was to evaluate approach–avoidance tendencies by using video recordings of postural body sway when participants were standing and observing facial expressions of pain, happy and neutral. We hypothesized that although pain faces would be rated as more unpleasant than the other faces, they would provoke significant changes in postural body sway as compared to neutral facial expressions. Forty healthy female volunteers (mean age 25) participated in the study. Amplitude of forward movements and backward movements in the anterior-posterior and medial-lateral axes were obtained. Statistical analyses revealed that pain faces were the most unpleasant stimuli, and that both happy and pain faces were more arousing than neutral ones. Happy and pain faces also elicited greater amplitude of body sway in the anterior-posterior axes as compared with neutral faces. In addition, significant positive correlations were found between body sway elicited by pain faces and pleasantness and empathic ratings, suggesting that changes in postural body sway elicited by pain faces might be associated with approach and cooperative behavioral responses.

Altered Functional Performance in Patients with Fibromyalgia

“… Kinematic parameters extracted from video recordings: gait velocity (cm/sec), gait duration (sec), cadence (steps/min), stride, and step lengths (cm), percentage of time in the stance/swing phase, and body sway variability in the anterior-posterior and medial-lateral planes (cm). Open-source software for computer vision analysis of human movement (CvMob; Peña et al, 2013 ; Gea et al, 2014 ; Quixadá et al, 2016 ) was used to extract those variables. This software has a high degree of accuracy for calculating body position and movement in the X and Y coordinates recorded by conventional cameras (Peña et al, 2013 ).…”

Como mulheres avaliam expressões faciais de alegria e dor?

“…164 de medidas de alterações posturais verificou que tanto as expressões de alegria quanto as de dor provocaram maior oscilação corporal de aproximação em comparação a faces neutras. Os autores consideraram que os efeitos da expressão de dor são diferentes daqueles induzidos por outros estímulos desagradáveis e que se assemelham ao da alegria no que concerne a tendência comportamental de aproximação e de evocação de maior empatia (Gea et al, 2014). Estudos de neuroimagem demonstraram que a empatia a dor ativa as regiões classicamente relacionadas com as redes neurais da empatia, tal como observado no estudo de metanálise de Jauniaux, Khatibi, Rainville e Jackson (2019).…”

An Observational Study Comparing Fibromyalgia and Chronic Low Back Pain in Somatosensory Sensitivity, Motor Function and Balance

“…Motion on the frontal and sagittal planes was captured with a digital video camera at 210 frames per second. For analyses of motion parameters, a free, open-source software for computer vision analysis of human movement was used (CvMob, 2011) [39]. This software has a high degree of accuracy for calculating body position and movement in the X and Y axes recorded by conventional cameras [40].…”