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71.
Abstract

This study assesses the relationship between friendship networks and academic performance among third graders from one school in Santiago, Chile. Longitudinal social network analysis (RSiena) was used to test whether friendship selection is driven by academic performance and if befriended peers tend to influence each other on their academic performance, including gender as a covariate. Results show a positive relationship between academic performance and number of friendship nominations received, and a higher probability of same-gender friendships. Students with higher academic achievement are more likely to be nominated as friends, especially by peers with lower academic achievement. These results suggest that elementary students value high performance as a desirable characteristic in their friends.  相似文献   
72.
Abstract

We present a computational model of the processes involved in retrieving stored semantic and name information from objects, using a simple interactive activation and competition architecture. We simulate evidence showing a cross-over in normal reaction times to make semantic classification and identification responses to objects from categories with either structurally similar or structurally dissimilar exemplars, and that identification times to objects from these two different classes correlate differentially with measures of the structural similarity of objects within the category and the frequency of the object's name. Structural similarity exerts a negative effect on object decision as well as naming, though this effect is larger on naming. Also, on naming, structural similarity interacts with the effects of name frequency, captured in the model by varying the weight on connections from semantic to name units; frequency effects are larger with structurally dissimilar items. In addition, (1) the range of potential errors for objects from these two classes, when responses are elicited before activation reached a stable state, differ–a wider range of errors occur to objects from categories with structurally similar exemplars; and (2) simulated lesions to different locations within the model produce selective impairments to identification but not to semantic classification responses to objects from categories with structurally similar exemplars. We discuss the results in relation to data on visual object processing in both normality and pathology.  相似文献   
73.
The goal of this study was to develop a measure of creativity that builds on the strengths of youth with autism spectrum disorders (ASD). The assessment of creativity focused on the visual-spatial abilities of these youth using 3D modeling software. One of the objectives of the research was to develop a measure of creativity in an authentic learning environment that built on the interests and creative talents of youth with ASD. Traditional creativity tests may underestimate the creativity of youth with ASD because of the tests’ constrained nature, such as having a time limit, being limited to paper and pencil, testing in an over- or understimulating environment, and overlooking visual-spatial ability. A random selection of 27 student 3D design projects (out of approximately 100 projects) was assessed using dimensions of fluency, flexibility, originality, and elaboration. The validity of this assessment was examined by comparing the creativity scores of the 27 projects to the creativity scores given by a team of Google experts (3D designers and software engineers). Results indicated that the scores were significantly correlated for three of the four dimensions of the creativity assessment. There was high inter-rater reliability among coders (M = .82) using intra-class correlation (ICC). Results suggest that this assessment process could be used as a visual-spatial creativity measure for youth with ASD, as well as a creativity measure used by employers to determine real-world creative potential in their employees, particularly those with neurodiversity.  相似文献   
74.
Model-based calculations indicate that reflex delay and reflex gain are both important for spinal stability. Experimental results demonstrate that chronic low back pain is associated with delayed muscle reflex responses of trunk muscles. The aim of the present study was to analyze the influence of such time-delayed reflexes on the stability using a simple biomechanical model. Additionally, we compared the model-based predictions with experimental data from chronic low back pain patients and healthy controls using surface-electromyography. Linear stability methods were applied to the musculoskeletal model, which was extended with a time-delayed reflex model. Lateral external perturbations were simulated around equilibrium to investigate the effects of reflex delay and gain on the stability of the human lumbar spine. The model simulations predicted that increased reflex delays require a reduction of the reflex gain to avoid spinal instability. The experimental data support this dependence for the investigated abdominal muscles in chronic low back pain patients and healthy control subjects. Reflex time-delay and gain dependence showed that a delayed reflex latency could have relevant influence on spinal stability, if subjects do not adapt their reflex amplitudes. Based on the model and the experimental results, the relationship between muscle reflex response latency and the maximum of the reflex amplitude should be considered for evaluation of (patho) physiological data. We recommend that training procedures should focus on speeding up the delayed reflex response as well as on increasing the amplitude of these reflexes.  相似文献   
75.
Organizations are frequently turning to social Internet applications in an effort to form bonds with consumers. However, little research has addressed the impact of social Internet consumption on the individual. Two studies of regular social Internet consumers (i.e., users of Facebook and socially connected online games) examined the effects of prompted usage reduction or cessation upon participants. In both studies, participants benefitted on average during the reduction/cessation period, reporting increased life satisfaction and decreased procrastination. The Facebooker versus gamer factor had remarkably few effects (i.e., results generalized across these two groups). Implications are discussed for both consumers and organizations involved in social Internet activities. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
76.
77.
This study explores oscillatory brain activity by means of event-related synchronization and desynchronization (%ERS/ERD) of EEG activity during the use of phonological and orthographic-morphological spelling strategies in L2 (English) and L1 (German) in native German speaking children. EEG was recorded while 33 children worked on a task requiring either phonological or orthographic-morphological spelling strategies. L2 processing elicited more theta %ERS than L1 processing (particularly at bilateral frontal and right posterior parietal sites) which might suggest a stronger involvement of semantic encoding and retrieval of the less familiar L2. The highest level of theta %ERS was revealed for the orthographic-morphological strategy in L2 which might indicate a more intense way of lexical retrieval compared to the phonological strategy in L2 and the orthographic-morphological strategy in L1. Analyses moreover revealed that phonological processing (both in L1 and L2) was associated with comparatively strong left-hemispheric %ERD in the upper alpha frequency band.  相似文献   
78.
This study examines a model relating components of organizational commitment to positive and negative affect through the partial mediation of problem solving coping. The results of a study conducted among a sample of 647 employees from various organizations show that affective commitment relates positively to positive affect and negatively to negative affect, with the relation to positive affect being partially mediated by problem solving coping. Normative commitment was positively related to negative affect. Finally, continuance commitment based on few alternatives was negatively related to positive affect and positively related to negative affect, with the relation to positive affect being partially mediated by a weaker problem solving coping. Continuance commitment based on perceived sacrifice had no effects.  相似文献   
79.
This study examined whether the effect of social group norms on 7‐ and 10‐year‐old children's aggression can be moderated or extinguished by contrary school norms. Children (n=384) participated in a simulation in which they were assigned membership in a social group for a drawing competition against an outgroup. Participants learnt that their group had a norm of inclusion, exclusion, or exclusion‐plus‐relational aggression, toward non‐group members, and that the school either had a norm of inclusion, or no such norm. Findings indicated that group norms influenced the participants' direct and indirect aggressive intentions, but that the school norm moderated the group norm effect, with the school's norm effect tending to be greater for indirect vs. direct aggression, males vs. females, and younger vs. older participants. Discussion focused on how school norms can be developed, endorsed, and presented so that they have their most lasting effect on children. Aggr. Behav. 36:195–204, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
80.
Responses to target stimuli can be encoded together with distracting objects accompanying these targets into a single stimulus-response episode or a single event file. Repeating any object of such an episode can trigger the response encoded in this episode. Hence, repeating a distractor may retrieve the response given to the target that was accompanied by this distractor. In the present experiments, we analyzed whether the binding of target responses to the distractor can be generalized even to the location of a distractor. In two experiments, we used a location-based prime-probe task and found that repeating the location of a distractor triggered the response to the target that had previously been accompanied by a distractor in the repeated location, even if the identity of the distractor changed from the prime to the probe.  相似文献   
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