基于QQ空间的社交网站使用对青少年抑郁的影响:上行社会比较和自尊的序列中介作用

为探讨社交网站(QQ空间)使用对青少年抑郁的影响及其作用机制,在社会比较和抑郁易感性模型的视角下,采用社交网站使用强度问卷、上行社会比较问卷、自尊量表和抑郁量表,对964名中学生进行调查。结果表明:(1)在控制了性别、年龄以及社交网站使用年限后,社交网站使用对抑郁和社交网站中的上行社会比较都有显著的正向预测作用;(2)社交网站使用能通过社交网站中的上行社会比较和自尊的中介作用对抑郁产生影响,且该中介作用包含了两条路径——上行社会比较的单独中介作用以及上行社会比较-自尊的链式中介作用。本研究揭示了社交网站使用与抑郁的关系及其作用机制,深化了社交网站使用对个体影响的研究。     

超声心动图与心血管造影X线引导下先心病介入封堵治疗的比较

目前先天性心脏病介入治疗已成为介入心脏病学的新热点,而先心病介入治疗离不开影像学引导,目前临床上常用的影像学引导方式主要有超声心动图和心血管造影两种,本文针对两者优缺点,从治疗方式、疗效、费用等方面进行比较,为临床治疗思路提供借鉴。     

Losing sight of oneself in the above-average effect: When egocentrism, focalism, and group diffuseness collide

Four experiments examined the relative influence of three causal processes in the above-average effect (AAE) and related comparative biases: (a) egocentrism, (b) focalism, and (c) referent group diffuseness. By manipulating the inclusion or exclusion of the self from the referent group (Experiments 1-3) or target group (Experiment 4), the relative contributions of each influence were assessed. In direct comparisons, single peers were systematically judged more favorably relative to groups including the self, suggesting that egocentrism plays a lesser role than focalism or group diffuseness. Thus, in response to the question such as “How friendly is Nancy compared to the rest of us?” the answer tends to be “More friendly.”     

简单结构刺激非规则特征突显条件下的样例效应

用变化了的Allen和Brooks的实验范式,采用2(学习轮次:5轮、10轮)×2(项目类型:旧项目、新项目)×2(项目匹配性质:正向匹配、反向匹配)混合实验设计,研究对4个特征刺激分类时非规则特征突显条件下的样例效应。结果发现,无论是错误率还是反应时都取得了明显的样例效应,但是学习时间的影响不明显。     

Social-comparative feedback affects motor skill learning

This study examined motivational effects of feedback on motor learning. Specifically, we investigated the influence of social-comparative feedback on the learning of a balance task (stabilometer). In addition to veridical feedback (error scores reflecting deviation from the target horizontal platform position) about their own performance after each trial, two groups received false normative information about the “average” score of others on that trial. Average performance scores indicated that the participant's performance was either above (better group) or below (worse group) the average, respectively. A control group received veridical feedback about trial performance without normative feedback. Learning as a function of social-comparative feedback was determined in a retention test without feedback, performed on a third day following two days of practice. Normative feedback affected the learning of the balance task: The better group demonstrated more effective balance performance than both the worse and control groups on the retention test. Furthermore, high-frequency/low-amplitude balance adjustments, indicative of more automatic control of movement, were greater in the better than in the worse group. The control group exhibited more limited learning and less automaticity than both the better and the worse groups. The findings indicate that positive normative feedback had a facilitatory effect on motor learning.     

The role of numerosity in processing nonsymbolic proportions

The difficulty in processing fractions seems to be related to the interference between the whole-number value of the numerator and the denominator and the real value of the fraction. Here we assess whether the reported problems with symbolic fractions extend to the nonsymbolic domain, by presenting fractions as arrays of black and white dots representing the two operands. Participants were asked to compare a target array with a reference array in two separate tasks using the same stimuli: a numerosity task comparing just the number of white dots in the two arrays; and a proportion task comparing the proportion of black and white dots. The proportion task yielded lower accuracy and slower response, confirming that even with nonsymbolic stimuli accessing proportional information is relatively difficult. However, using a congruity manipulation in which the greater numerosity of white dots could co-occur with a lower proportion of them, and vice versa, it was found that both task-irrelevant dimensions would interfere with the task-relevant dimension suggesting that both numerosity and proportion information was automatically accessed. The results indicate that the magnitude of fractions can be automatically and holistically processed in the nonsymbolic domain.     

A Dissociation between Symbolic Number Knowledge and Analogue Magnitude Information

Semantic understanding of numbers and related concepts can be dissociated from rote knowledge of arithmetic facts. However, distinctions among different kinds of semantic representations related to numbers have not been fully explored. Working with numbers and arithmetic requires representing semantic information that is both analogue (e.g., the approximate magnitude of a number) and symbolic (e.g., what / means). In this article, the authors describe a patient (MC) who exhibits a dissociation between tasks that require symbolic number knowledge (e.g., knowledge of arithmetic symbols including numbers, knowledge of concepts related to numbers such as rounding) and tasks that require an analogue magnitude representation (e.g., comparing size or frequency). MC is impaired on a variety of tasks that require symbolic number knowledge, but her ability to represent and process analogue magnitude information is intact. Her deficit in symbolic number knowledge extends to a variety of concepts related to numbers (e.g., decimal points, Roman numerals, what a quartet is) but not to any other semantic categories that we have tested. These findings suggest that symbolic number knowledge is a functionally independent component of the number processing system, that it is category specific, and that it is anatomically and functionally distinct from magnitude representations.     

Erkenntnistheorie der Zahldefinition und philosophische Grundlegung der Arithmetik unter Bezugnahme auf einen Vergleich von Gottlob Freges Logizismus und platonischer Philosophie (Syrian, Theon von Smyrna u.a.)

The epistomology of the definition of number and the philosophical foundation of arithmetic based on a comparison between Gottlob Frege's logicism and Platonic philosophy (Syrianus, Theo Smyrnaeus, and others). The intention of this article is to provide arithmetic with a logically and methodologically valid definition of number for construing a consistent philosophical foundation of arithmetic. The – surely astonishing – main thesis is that instead of the modern and contemporary attempts, especially in Gottlob Frege's Foundations of Arithmetic, such a definition is found in the arithmetic in Euclid's Elements. To draw this conclusion a profound reflection on the role of epistemology for the foundation of mathematics, especially for the method of definition of number, is indispensable; a reflection not to be found in the contemporary debate (the predominate ‘pragmaticformalism’ in current mathematics just shirks from trying to solve the epistemological problems raised by the debate between logicism, intuitionism, and formalism). Frege's definition of number, ‘The number of the concept F is the extension of the concept ‘numerically equal to the concept F”, which is still substantial for contemporary mathematics, does not fulfil the requirements of logical and methodological correctness because the definiens in a double way (in the concepts ‘extension of a concept’ and ‘numerically equal’) implicitly presupposes the definiendum, i.e. number itself. Number itself, on the contrary, is defined adequately by Euclid as ‘multitude composed of units’, a definition which is even, though never mentioned, an implicit presupposition of the modern concept ofset. But Frege rejects this definition and construes his own - for epistemological reasons: Frege's definition exactly fits the needs of modern epistemology, namely that for to know something like the number of a concept one must become conscious of a multitude of acts of producing units of ‘given’ representations under the condition of a 1:1 relationship to obtain between the acts of counting and the counted ‘objects’. According to this view, which has existed at least since the Renaissance stoicism and is maintained not only by Frege but also by Descartes, Kant, Husserl, Dummett, and others, there is no such thing as a number of pure units itself because the intellect or pure reason, by itself empty, must become conscious of different units of representation in order to know a multitude, a condition not fulfilled by Euclid's conception. As this is Frege's main reason to reject Euclid's definition of number (others are discussed in detail), the paper shows that the epistemological reflection in Neoplatonic mathematical philosophy, which agrees with Euclid's definition of number, provides a consistent basement for it. Therefore it is not progress in the history of science which hasled to the a poretic contemporary state of affairs but an arbitrary change of epistemology in early modern times, which is of great influence even today. This revised version was published online in August 2006 with corrections to the Cover Date.     

Choice and multiple reinforcers

Pigeons chose between equivalent two-component mixed and multiple terminal-link schedules of reinforcement in the concurrent-chains procedure. The pigeons preferred the multiple schedule over the mixed when the components of the compound schedules were differentiated in terms of density of reinforcement, but the pigeons were indifferent when the components were differentiated in terms of number of reinforcers per cycle. Taken together, these results indicate that a local variable, the interval to the first reinforcer, but not a molar variable, the number of reinforcers, was sufficient to differentiate the components and thereby evoke preference.