Posture-movement responses to stance perturbations and upper limb fatigue during a repetitive pointing task

Localized muscle fatigue and postural perturbation have separately been shown to alter whole-body movement but little is known about how humans respond when subjected to both factors combined. Here we sought to quantify the kinematics of postural control and repetitive upper limb movement during standing surface perturbations and in the presence of fatigue. Subjects stood on a motion-based platform and repetitively reached between two shoulder-height targets until noticeably fatigued (rating of perceived exertion = 8/10). Every minute, subjects experienced a posterior and an anterior platform translation while reaching to the distal target. Outcomes were compared prior to and with fatigue (first vs. final minute data). When fatigued, regardless of the perturbation condition, subjects decreased their shoulder abduction and increased contralateral trunk flexion, a strategy that may relieve the load on the fatiguing upper limb musculature. During perturbations, kinematic adaptations emerged across the trunk and arm to preserve task performance. In contrast to our expectation, the kinematic response to the perturbations did not alter in the presence of fatigue. Kinematic adaptations in response to the perturbation predominantly occurred in the direction of the reach whereas fatigue adaptations occurred orthogonal to the reach. These findings suggest that during repetitive reaching, fatigue and postural perturbation compensations organize so as to minimize interaction with each other and preserve the global task characteristics of endpoint motion.     

OVERCOMING INTERNALISED PHOBIA AMONG BUDDHIST SEXUAL MINORITIES THROUGH MINDFULNESS

ABSTRACT

When heterosexuality dominates sexual culture, sexual minorities are marginalised, yielding minority stress and internalised phobia which devastate psychological well-being and raise suicide risks. A growing trend in using mindfulness-related interventions in health care shows positive signs, but there is a paucity of research on mindfulness for sexual minorities. This qualitative research, through interpretative phenomenological analysis, looks into how Buddhist sexual minorities (from various countries) interpret mindfulness from which their increased self-awareness, self-esteem and self-acceptance become prominent intrinsic resources, resulting in enhanced mental health and quality of life. Such an exploratory study extends the horizon of health care benefits for helping professionals and sexual minorities with alternative views in overcoming external and internalised phobia.     

Suffering by comparison: Twitter users’ reactions to the Victoria's Secret Fashion Show

Social comparison theory suggests that evaluating the self in comparison with others (e.g., peers, celebrities, models) can influence body image. Experimental studies that have tested effects of viewing idealized images in the media often show that women feel worse about themselves after seeing images that illustrate the beauty ideal. Twitter presents a naturally occurring opportunity to study viewers’ reactions. An analysis was conducted of 977 tweets sent immediately before and during the 2011 Victoria's Secret Fashion Show that reference the show. Although the majority were idiosyncratic remarks, many tweets contain evidence of upward social comparisons to the fashion models. There were tweets about body image, eating disorders, weight, desires for food or alcohol, and thoughts about self-harm. The results support social comparison theory, and suggest that vulnerable viewers could experience negative affect, or even engage in harmful behaviors, during or after viewing the show or others like it.     

Body dissatisfaction, maternal appraisal, and depressive symptoms in Hong Kong adolescents

Body dissatisfaction, its risk factors and association with depressed mood have been well investigated in the West. However, more studies are needed to examine further the relation between body dissatisfaction and depressive symptoms and the factors influencing body dissatisfaction in non-Western cultures. The present study examined in a sample of Hong Kong Chinese adolescents the relation between body dissatisfaction and depressive symptoms, and the relation of maternal appraisal of their adolescent's figure to the adolescent's body dissatisfaction and depressive symptoms. We obtained information from 379 boys and 254 girls about their body dissatisfaction and depressive symptoms. Their mothers provided information about their appraisal of their adolescent's body shape and size compared to ideal. Body dissatisfaction was related to depressive symptoms in girls (B = 2.58, p <.01), but not in boys (B = -0.08, p >.10). Negative maternal appraisal did not have direct effects on adolescents' depressive symptoms (B = 0.14, p =.75), but the association between negative maternal appraisal and body dissatisfaction was significantly stronger in adolescents whose ideal was smaller than they perceived themselves to be (B = 0.32, p <.01) than those whose ideal was larger than their own perception (B = 0.14, p < .01). Our findings suggest that maternal appraisal had indirect effects on mood, acting through adolescents' body dissatisfaction, and that body dissatisfaction may be a sex-specific risk factor for depression. This study points to the need for testing and adapting programs to reduce body dissatisfaction particularly in girls at risk for depression, and to raise mothers' awareness of the link between their negative appraisals and their adolescents' body dissatisfaction and depressive symptoms.     

A treadmill and motion coupled virtual reality system for gait training post-stroke.

A virtual reality (VR)-based locomotor training system has been developed for gait rehabilitation post-stroke. The system consists of a self-paced treadmill mounted onto a 6-degrees-of-freedom motion platform. Virtual environments (VEs) that are synchronized with the speed of the treadmill and the motions of the platform are rear-projected onto a screen in front of the walking subject. A feasibility study was conducted to test the capability of two stroke patients and one healthy control to be trained with the system. Three VE scenarios (corridor walking, street crossing, and park stroll) were woven into a gait-training program that provided three levels of complexity (walking speed, slopes, collision avoidances), progression criteria (number of successful trials) and knowledge of results. Results show that, with practice, patients can effectively increase their gait speed as demanded by the task and adapt their gait with respect to the change in physical terrain. However, successful completion of tasks requiring adaptation to increasing demands related to speed and physical terrains does not necessarily predict the patient's ability to anticipate and avoid collision with obstacles during walking. This feasibility study demonstrates that persons with stroke are able to adapt to this novel VR system and be immersed in the VEs for gait training.     

Self-Evaluation Bias of Social Comparisons in Ethical Decision Making: The Impact of Accountability

The purpose of this paper is to examine how accountability and judgment biases that occur in social comparisons may be related to ethical decision making. Using Jones' (1991 ) model as the theoretical framework to investigate this phenomenon, we found that self-enhancing individuals (i.e., those who thought they were more ethical in comparison to their peers) demonstrated higher responsiveness to increases in accountability than did self-effacing individuals (i.e., those who thought they were less ethical in comparison to their peers). We discuss these findings and outline the implications for future ethics research. Further, we provide practical guidance to those who administer ethics compliance programs on effective ways of facilitating ethical behavior in organizations.     

Attentional SNARC: there's something special about numbers (let us count the ways)

We report a study that examines whether the presentation of irrelevant, ordinal information at central fixation interacts with the allocation of attention beyond fixation. Previous research has demonstrated that number perception influences the allocation of spatial attention, such that the presentation of a spatially nonpredictive number at fixation results in attention being allocated to the left when the central number is low (e.g., 1), and attention being allocated to the right when the central number is high (e.g., 9). Here, we examine whether this attentional SNARC effect (spatial numerical association of response codes) generalizes to other ordinal sequences: letters, days, and months. Though we replicate the attentional SNARC we find that this effect is number-specific, unless participants are required to process the cue in an order-relevant fashion. This discovery of number-specificity has important implications both for the functional separation between SNARC and attention-SNARC effects, as well as lending support to recent theories regarding the specificity of a shared neural architecture between numbers and visuospatial attention.