Phase Correction Following a Perturbation in Sensorimotor Synchronization Depends on Sensory Information

In models of sensorimotor synchronization, it is generally assumed that phase correction occurs in response to information about sensorimotor asynchrony or relative phase. Without such feedback, a phase perturbation in the motor activity should not be followed by phase correction. Alternatively, internally generated temporal expectations could provide a basis for phase correction in the absence of feedback. To test those hypotheses, the author conducted an experiment in which participants (N = 8) tapped their finger in synchrony with isochronous auditory sequences containing a single shifted event onset, after which there could be a gap of up to 3 missing events. Participants were instructed to not react to the shifted event and to continue tapping regularly during any gap. The shifted event caused an involuntary phase shift of the following tap. The shift was corrected if the sequence continued, but during a gap, the shift persisted without correction. Those results confirm that sensory feedback is necessary for phase correction to occur.     

More than just body weight: The role of body image in psychological and physical functioning

The current study examined BMI and body image dissatisfaction as predictors of physical and mental health-related quality of life (HRQL) and psychosocial functioning in a sample of 414 undergraduate students (mean age = 21.5, SD = 4.9; mean BMI = 23.6, SD = 5.2). In men and women, higher BMI was correlated with body image dissatisfaction and physical HRQL, but not with any measures of psychosocial functioning, whereas higher body image dissatisfaction was associated with poorer physical HRQL and psychosocial functioning. Furthermore, body image dissatisfaction was observed to mediate the relationship between BMI and physical HRQL in men and women. Interestingly, in this model, higher BMI predicted increased self-esteem. These findings suggest that body image dissatisfaction may be an important target for health interventions.     

肥胖男性血浆脂联素水平及影响因素

检测正常男性血浆脂联素水平,探讨其与各检测指标之间的相关性。选取正常男性96例,按体重指数（BMI）将上述两组分为2个亚组：肥胖（BMI≥25kg／m^2）组40例及体重正常（BMI〈25kg／m^2）组56例,测定空腹血浆脂联素浓度。肥胖组的血浆脂联素水平[（7．48±3．4）μg／m1]明显低于体重正常组[（10．57±4．73）μg／m1],差异有显著的统计学意义（P〈0．01）。相关分析显示血浆脂联素与体重指数（BMI）、腰围（WC）、血压（BP）、总胆固醇（TC）、血清胰岛素（FINs）、胰岛素抵抗指数（HOMA-IR）之间存在负相关,与高密度脂蛋白胆固醇（HDL-C）正相关。BMI、WC、HOMA-IR为影响血浆脂联素水平的独立因素。男性肥胖者血浆脂联素水平较体重正常者明显降低,血浆脂联素水平可能与肥胖及其相关疾病相关。     

Self-compassion moderates the relationship between body mass index and both eating disorder pathology and body image flexibility

The current study examined whether self-compassion, the tendency to treat oneself kindly during distress and disappointments, would attenuate the positive relationship between body mass index (BMI) and eating disorder pathology, and the negative relationship between BMI and body image flexibility. One-hundred and fifty-three female undergraduate students completed measures of self-compassion, self-esteem, eating disorder pathology, and body image flexibility, which refers to one's acceptance of negative body image experiences. Controlling for self-esteem, hierarchical regressions revealed that self-compassion moderated the relationships between BMI and the criteria. Specifically, the positive relationship between BMI and eating disorder pathology and the negative relationship between BMI and body image flexibility were weaker the higher women's levels of self-compassion. Among young women, self-compassion may help to protect against the greater eating disturbances that coincide with a higher BMI, and may facilitate the positive body image experiences that tend to be lower the higher one's BMI.     

Vertical adaptation of the center of mass in human running on uneven ground

In running we are frequently confronted with different kinds of disturbances. Some require quick reactions and adaptations while others, like moderate changes in ground level, can be compensated passively. Monitoring the kinematics of the runner’s center of mass (CoM) in such situations can reveal what global locomotion control strategies humans use and can help to distinguish between active and passive compensation methods.In this study single and permanent upward steps of 10 cm as well as drops of the same height were used as mechanical disturbances and the adaptations in the vertical oscillation of the runners CoM were analyzed. We found that runners visually perceiving uneven ground ahead substantially adapted their CoM in preparation by lifting it about 50% of step height or lowering it by about 40% of drop height, respectively. After contact on the changed ground level different adaptations depending on the situation occur. For persisting changes the adaptation to the elevated ground is completed after the first step on the new level. For single steps part of the adaptation takes place while returning to the ground. The consistent adaptations for the different situations support the idea that controlling the CoM by adapting leg parameters is a general control principle in running.     

A self-determination theory approach to adults’ healthy body weight motivation: A longitudinal study focussing on food choices and recreational physical activity

This study focuses on body weight motivation based on self-determination theory. The impact of body weight motivation on longitudinal changes in food choices, recreational physical activity and body mass index was explored. A sample of adults (N = 2917, 47% men), randomly selected from the telephone book, completed a questionnaire in two consecutive years (2012, 2013), self-reporting food choices, recreational physical activity and body weight motivation. Types of body weight motivation at T1 (autonomous regulation, introjected regulation, and external regulation) were tested with regard to their predictive potential for changes in food choices, recreational physical activity and body mass index (BMI). Autonomous motivation predicted improvements in food choices and long-term adherence to vigorous recreational physical activity in both genders. Introjected motivation predicted long-term adherence to vigorous recreational physical activity only in women. External motivation predicted negative changes in food choices; however, the type of body weight motivation had no impact on BMI in overweight adults in the long term. Autonomous goal-setting regarding body weight seems to be substantial for healthy food choices and adherence to recreational physical activity.     

The impact of weight, sex, and race/ethnicity on body dissatisfaction among urban children

The purpose of the current study was to examine the relative contributions of weight status, race/ethnicity, sex, and age on body dissatisfaction in a large group of diverse children. Participants were 4th–6th graders (N = 1212) in ten inner-city schools who participated in an obesity prevention study previously published. Children completed the body dissatisfaction subscale of the Eating Disorder Inventory-2 (EDI-2), and weight status was assessed by measured weights and heights. Multiple regression analyses were conducted. Relative weight status was the strongest predictor of body dissatisfaction, followed by race/ethnicity, and sex. Body dissatisfaction was greatest in obese, Asian, and female children. Overall, results indicated that children's body dissatisfaction varies based on relative weight status, as well as race/ethnicity and sex among urban children. Results highlight the strong need for additional research so that more definitive conclusions may be drawn regarding the development of body image among diverse groups of children.     

Reexamining the Calculus of Voting

This study applies social cognitive theory to the study of voter turnout, examining the effects of self‐efficacy on citizens' decisions of whether or not to vote. Consistent with recent arguments in cognitive psychology ( Fenton‐O'Creevy, Nicholson, Soane, & Willman, 2003, 2005 ), I argue that excessive perceptions of self‐efficacy lead some citizens to overestimate their vote's impact in close elections and to vote as a consequence of these perceptions. This illusion of control is further engendered by the features of skill‐based activities such as choice, personal involvement, stimulus familiarity, and exertion of effort ( Langer, 1975 ) that are inherent in the act of voting. Employing both cross‐sectional and panel data, I find that individuals with high levels of self‐efficacy are more likely to be moved to vote by perceptions that an election will be close than are citizens with low levels of self‐efficacy.     

群体性事件形成的心理机制分析

我国正处在社会转型时期,由各利益主体之间的磨擦而引发的群体性事件日益增多,诱发群体性事件的原因也复杂多样。如果从人类行为发生的内在机理看,它们主要遵循刺激——反应机制。导致群体性事件的发生既有直接诱因,也包括弱势群体的大量存在等社会诱因,而各种认识的偏差则是群体性事件的主观心理性因素。我们只有通过改变条件或作用方式,正确调整社会心理,使群体性事件丧失其发生的前提,才能达到预警预防群体性事件的目的。     

Movement segmentation and visual perturbation increase developmental differences in motor control and learning

We examined the developmental differences in motor control and learning of a two‐segment movement. One hundred and five participants (53 female) were divided into three age groups (7–8 years, 9–10 years and 19–27 years). They performed a two‐segment movement task in four conditions (full vision, fully disturbed vision, disturbed vision in the first movement segment and disturbed vision in the second movement segment). The results for movement accuracy and overall movement time show that children, especially younger children, are more susceptible to visual perturbations than adults. The adults’ movement time in one of the movement segments could be increased by disturbing the vision of the other movement segment. The children's movement time for the second movement segment increased when their vision of the first movement segment was disturbed. Disturbing the vision of the first movement segment decreased the percentage of central control of the second movement in younger children, but not in the other two age groups. The children's normalized jerk was more easily increased by visual perturbations. The children showed greater improvement after practice in the conditions of partial vision disturbance. As the participants’ age increased, practice tended to improve their feedforward motor control rather than their feedback motor control. These results suggest that children's central movement control improves with age and practice. We discuss the theoretical implications and practical significance of the differential effects of visual perturbation and movement segmentation upon motor control and learning from a developmental viewpoint.