Synergies and Motor Equivalence in Voluntary Sway Tasks: The Effects of Visual and Mechanical Constraints

The authors used two analyses developed within the framework of the uncontrolled manifold hypothesis to quantify multimuscle synergies during voluntary body sway: analysis of intertrial variance and analysis of motor equivalence with respect to the center of pressure (COP) trajectory. Participants performed voluntary sway tasks in the anteroposterior direction at 0.33 and 0.66 Hz. Muscle groups were identified in the space of muscle activations and used as elemental variables in the synergy analyses. Changing mechanical and vision feedback–based constraints led to significant changes in indices of sway performance such as COP deviations in the uninstructed, mediolateral direction and indices of spontaneous postural sway. In contrast, there were no significant effects on synergy indices. These findings show that the neural control of performance and of its stability may involve different control variables and neurophysiological structures. There were strong correlations between the indices of motor equivalence and those computed using the intercycle variance analysis. This result is potentially important for studies of patients with movement disorders who may be unable to perform multiple trials (cycles) at any given task, making analysis of motor equivalence of single trials a viable alternative to explore changes in stability of actions.     

The Joint Multivariate Modeling of Multiple Mixed Response Sources: Relating Student Performances with Feedback Behavior

The present study concerns a Dutch computer-based assessment, which includes an assessment process about information literacy and a feedback process for students. The assessment is concerned with the measurement of skills in information literacy and the feedback process with item-based support to improve student learning. To analyze students’ feedback behavior (i.e. feedback use and attention time), test performance, and speed of working, a multivariate hierarchical latent variable model is proposed. The model can handle multivariate mixed responses from multiple sources related to different processes and comprehends multiple measurement components for responses and response times. A flexible within-subject latent variable structure is defined to explore multiple individual latent characteristics related to students’ test performance and feedback behavior. Main results of the computer-based assessment showed that feedback-information pages were less visited by well-performing students when they relate to easy items. Students’ attention paid to feedback was positively related to working speed but not to the propensity to use feedback.     

Symptoms,blood-pressure information and mood effects on symptom recall

Abstract

After completion of an illness symptom checklist (PILL) covering the previous three months, 97 nor-motensives were allocated to either experimental (false pressor feedback, n=42), or information control (accurate pressor feedback, n = 55), groups. The median reported symptom score divided high from low symptom subjects. All were given standard cuff blood pressure (BP) assessment and were normotensive. However, experimental subjects were misinformed that their BP was raised while information control subjects were told their BP was normal. Subsequently, subjects completed the state anxiety form of the State-Trait Personality Inventory, the PILL, and were asked about their belief of the ascribed BP label (normo/hypertensive) and then any perceived causal relationship between their BP and symptoms. Experimental subjects had significantly higher anxiety scores but no change in symptom recall after pressor feedback, whereas control subjects showed lower anxiety scores and decreases in symptom recall.

A post hoc treatment control (no pressor information) group (n = 20) excluded effects of BP labeling on post-BP scores, and a post hoc symptom control group (n = 55) ensured that symptom levels were representative of the normal population. The majority of subjects in both groups rejected any association between BP labels and symptoms. Data are discussed in the light of Leventhal's models of illness representation.     

不同列队呈现方式下反馈对目击证人辨认自信心的影响

采用辨认后反馈范式研究不同队列呈现方式下反馈对目击证人辨认自信心的影响。结果发现：（1）所有辨认者中,反馈组被试自信心显著高于控制组被试的自信心;反馈方式与辨认选择的交互作用显著,辨认选择与列队呈现方式的交互作用显著;（2）积极辨认者中,反馈组被试的自信心显著高于控制组被试的自信心;正确辨认被试的自信心显著高于错误辨认被试的自信心。结果表明：目击辨认中存在辨认后反馈效应;积极辨认者中辨认自信心可以作为辨认准确性的一个参考指标。     

The Reflected Best Self field experiment with adolescent leaders: exploring the psychological resources associated with feedback source and valence

This study provides a preliminary examination of the efficacy of the Reflected Best Self Exercise. We conducted a field quasi-experiment with 108 adolescent leaders assigned to a 2 × 2 design: (1) valence of feedback (i.e., strengths-only versus strengths and improvement-oriented) and (2) source of feedback (i.e., professional (e.g., teachers, coaches, bosses) only versus professional and personal (e.g., friends and family)). By ANOVA, support was found for the hypothesis that feedback from the combination of professional and personal sources is associated with more positive emotional, agentic, and relational resources than feedback from only professional sources. Little support was found for the hypothesis that strengths-based feedback generates more positive emotional, agentic, or relational resources. Limitations, implications for practice and directions for future research are discussed.     

The effects of feedback on the gender differences in the performance in a chronometric mental-rotation test

ABSTRACT

Gender differences favouring males are often found in mental-rotation tests and are usually smaller in chronometric than in psychometric test. The individual feedback in the chronometric test could be an explanation for the comparable performance of males and females. To test this hypothesis, 102 undergraduate students (60 females, 42 males) participated in a chronometric mental-rotation study with or without feedback. A subsample of 41 participants was asked to report their confidence about their performance in the test. In reaction time, males outperformed females and participants in the feedback condition reacted faster than participants without feedback. A significant interaction of gender and condition was found. Only females had an advantage in the feedback condition in reaction time while there was no difference for males. Males reported higher scores of confidence. Feedback seemed to help females especially to react faster. Confidence levels are discussed as reasons for differences between conditions and genders.     

Psychological needs,purpose in life,and problem video game playing among Chinese young adults

The negative impacts of excessive and problematic video game playing on both children and adults are attracting increasing concern. Based on self‐determination theory (SDT; Ryan & Deci, 2000), this study hypothesized that the three basic psychological needs of autonomy, competence, and relatedness are positively associated with purpose in life, which in turn acts as a protective factor against problem video game playing among Chinese young adult players. Through a questionnaire survey with a sample of 165 Chinese adults aged between 18 and 30 years (mean age = 22.7 years), we found that perceived autonomy, competence, relatedness, and purpose in life were all negatively correlated with problem game playing. The demographic and psychological factors explained 38% of the variances of problem game playing. Specifically, gender, perceived relatedness, and purpose in life emerged as the three most salient predictors of problem game playing among the Chinese young adults. The mediating role of purpose in life was evidenced and it was found that purpose in life mediated the influences of the psychological needs proposed by SDT on problem game playing. Moreover, young men were significantly more susceptible to problem game playing than their female counterparts. To conclude, psychological needs and purpose in life influenced Chinese young adults’ vulnerability to problem game playing directly or indirectly. Intervention programs that encourage social involvement and voluntary work, as well as counseling service that helps clients to search for life purpose, are suggested for intervening in problem game playing among Chinese young adults.     

Reliability and Specificity of Individual Differences In Reminiscence

In investigating Eysenck’s (1965) suggestion of the specificity of reminiscence, 50 high school boys were tested on 2 gross motorcoordination tasks—one involving tracking and the other balance. In the practice schedule, which was identical for both tasks, all Ss were given 20 50-sec. trials with a 10-sec. intertrial rest. A 5-min. interpolated rest was given after every fourth trial. The reliability of individual differences in reminiscence for both tasks was found to be extremely low. While Eysenck’s hypothesis was not necessarily weakened, doubt was cast upon the specificity of reminiscence in the usual context of the word.     

Challenge Point: A Framework for Conceptualizing the Effects of Various Practice Conditions in Motor Learning

The authors describe the effects of practice conditions in motor learning (e.g., contextual interference, knowledge of results) within the constraints of 2 experimental variables: skill level and task difficulty. They use a research framework to conceptualize the interaction of those variables on the basis of concepts from information theory and information processing. The fundamental idea is that motor tasks represent different challenges for performers of different abilities. The authors propose that learning is related to the information arising from performance, which should be optimized along functions relating the difficulty of the task to the skill level of the performer. Specific testable hypotheses arising from the framework are also described.     

Effects of Auditory Feedback on Movement Time in a Fitts Task

The purpose of the present experiment was to investigate the role of auditory feedback and its impact on movement time in a standard Fitts task. Feedback was given at the moment of target acquisition. A 2-way analysis of variance found significant differences between feedback groups at all three indexes of difficulty (F(2, 40) = 156.02, p < .001). Results from a mixed-model multivariate analysis of variance for kinematic factors show significant differences in peak velocity and the location of peak velocity when comparing feedback groups. In general, the addition of auditory feedback decreased the task ID by .5.