Impairment of spatial learning and hippocampal synaptic potentiation in c-kit mutant rats

The c-kit receptor tyrosine kinase encoded by the white-spotting (W) gene is highly expressed in rat hippocampal CA1–CA4 regions. We found an impaired spatial learning and memory in homozygous c-kit (Ws/Ws) mutant rats that have a 12-base deletion in the tyrosine kinase domain of the c-kit gene and a very low kinase activity. Electrophysiological studies in hippocampal slices revealed that the long-term potentiation (LTP) induced by the tetanic stimulation (100 Hz, 1 sec) in the mossy fiber (MF)–CA3 pathway, but not in the Schaffer collaterals/commissural–CA1 pathway, was significantly reduced in c-kit mutants compared with wild-type (+/+) rats. The paired-pulse facilitation (PPF) was measured before the tetanus and after the establishment of the LTP in each slice. The initial PPF in the MF–CA3 pathway positively correlated with the amplitude of the LTP in the wild-type rats but not in the c-kit mutant rats. Furthermore, they failed to show the normal characteristics observed in the MF–CA3 pathway of +/+ rats; that is, the negative correlation between the initial PPF and the changes in PPF measured after the LTP. These findings suggest an involvement of SCF/c-kit signaling in hippocampal synaptic potentiation and spatial learning and memory.     

The differential effects of thalamus and basal ganglia on facial emotion recognition

This study examined if subcortical stroke was associated with impaired facial emotion recognition. Furthermore, the lateralization of the impairment and the differential profiles of facial emotion recognition deficits with localized thalamic or basal ganglia damage were also studied. Thirty-eight patients with subcortical strokes and 19 matched normal controls volunteered to participate. The participants were individually presented with morphed photographs of facial emotion expressions over multiple trials. They were requested to classify each of these morphed photographs according to Ekman's six basic emotion categories. The findings indicated that the clinical participants had impaired facial emotion recognition, though no clear lateralization pattern of impairment was observed. The patients with localized thalamic damage performed significantly worse in recognizing sadness than the controls. Longitudinal studies on patients with subcortical brain damage should be conducted to examine how cognitive reorganization post-stroke would affect emotion recognition.     

早期佛教僧团管理的经济制度——利和同均

本文就饮食、衣物等日用资具,僧物与私人物之划分,说明早期佛教僧团经济之来源与实际分配之制度运作。指出早期佛教僧团管理的经济制度,是以利和同均之团体分配原则,辅以个人诫慎行持与戒法威德之助成,经济制度之完备,构筑了衣食无虞,互敬互利,和合无诤之僧团,令僧众能专心修行,趋向解脱大道。     

Using the open-source statistical language R to analyze the dichotomous Rasch model

R, an open-source statistical language and data analysis tool, is gaining popularity among psychologists currently teaching statistics. R is especially suitable for teaching advanced topics, such as fitting the dichotomous Rasch model-a topic that involves transforming complicated mathematical formulas into statistical computations. This article describes R’s use as a teaching tool and a data analysis software program in the analysis of the Rasch model in item response theory. It also explains the theory behind, as well as an educator’s goals for, fitting the Rasch model with joint maximum likelihood estimation. This article also summarizes the R syntax for parameter estimation and the calculation of fit statistics. The results produced by R is compared with the results obtained from MINI STEP and the output of a conditional logit model. The use of R is encouraged because it is free, supported by a network of peer researchers, and covers both basic and advanced topics in statistics frequently used by psychologists.     

Learning as a task or a virtue: U.S. And Chinese preschoolers explain learning

The purpose of this study was to examine cultural influences on conceptual orientations of learning in U.S. and Chinese preschoolers. A sample of 188 preschoolers 4-6 years of age provided free-narrative responses to 2 story beginnings about the learning behavior of 2 protagonists, 1 who worked hard and 1 who gave up. Results showed that despite some differences in the younger age groups, children from both cultures valued learning similarly at age 6. However, important cultural differences emerged in children's construals of the learning process. U.S. children showed a heightened awareness of the mind/task attributes of the learner, that is, ability, task attempting, and strategy use. By contrast, Chinese children perceived more the learner's dispositional qualities of diligence, persistence, and concentration. These trends increased as children's age increased. The U.S. findings are interpreted as reflecting the U.S. cultural emphasis on learning as a task, and the Chinese results, as reflecting the Chinese cultural focus on learning as a process of cultivating personal virtue.     

Stability and variability may respond differently to changes in walking speed

In gait research it has often been assumed that variability and stability are negatively correlated, where increases in variability are assumed to equate with increases in instability. The purpose of this paper is to illustrate that variability does not always equate with stability. To proof this point, a method was developed to directly assess stability and variability during the application of a visual perturbation at different walking speeds. Walking variability was measured by using the average standard deviation of the knee joint angle across the gait cycle. Walking stability was measured by the recovery time of the knee joint angle trajectory from the distortion induced by a visual perturbation that was delivered at the beginning of the stance phase. Five participants were required to walk at six different velocities on a treadmill (0.67, 0.80, 0.94, 1.07, 1.21, and 1.34 m/s). The coefficients of intraclass correlations for the experiment were 83% and 80% for the calculated stability and variability, respectively. The calculated stabilities were not sensitive to changes in walking speed (p>0.98). The calculated variability however decreased with increases in walking speed (p=0.004). No significant correlation between variability and stability was observed (r=-0.002). We suggest that gait stability is independent of variability during locomotion and should thus be measured independently.     

青少年的人格特征与互联网信息服务使用的关系

互联网上的信息服务为青少年的个性化学习提供了可能,如何使青少年健康地进行网上冲浪,使他们在冲浪的过程中增强自律意识,就需要我们深入地了解互联网信息服务在哪些方面能够满足青少年的需要。该研究通过对339名中学生进行问卷调查,对青少年的人格特征、社会支持与互联网信息服务之间的关系进行了探讨,结果表明:(1)开放性、客观社会支持和对社会支持的利用对互联网信息服务的使用偏好有直接而显著的影响。(2)宜人性和外向性通过社会支持的三个方面间接地对互联网信息服务的使用偏好产生影响。(3)客观社会支持会影响主观社会支持,主观社会支持对社会支持的利用水平也有影响。     

非英语专业大学生短文写作元认知发展的一般特点

对1043名大学生(有效被试1012人)进行英文写作元认知、自我效能、成就目标、价值、内控性的测量,旨在了解非英语专业大学生英文写作元认知各维度的一般性发展特点。结果发现:语言策略、作文标准、准备性和计划性上存在年级差异;对作为作者的自己的优点的了解、对作为作者的自己的缺点的了解、语言策略知识、元认知体验、计划性、准备性、调节性上存在性别差异;在英文写作自我效能、价值、成就目标、内控性高分组与低分组间元认知水平差异达到显著性,且高分组具有较高的英文写作元认知水平。