The unilateral field advantage in repetition detection: Effects of perceptual grouping and task demands

This study examines interhemispheric interactions in detecting objects that are simultaneously repeated in an array of objects. Previous studies have shown that presenting two identical objects to a single hemifield speeds up repetition detection. This unilateral field advantage (UFA) is often attributed to the relatively low-level processing demands for detecting a perceptual repetition, and more specifically, to more efficient perceptual grouping processes within a hemisphere than between hemispheres. To directly examine the impact of perceptual grouping and task demands on interhemispheric interactions, we asked participants to judge whether four items, one presented in each visual quadrant, were all different, or whether any two were the same, along an instructed dimension. We found that in comparison with the UFA for identical objects, the UFA for repetition detection in accuracy was similar or greater when the matching objects were not perceptually identical and differed in color, size, or viewpoint. Thus, decreasing grouping strength and increasing computational complexity did not reduce the UFA. Results are interpreted in terms of the callosal degradation account of the UFA.     

Stress-enhanced grain growth in a nanostructured aluminium alloy during spark plasma sintering

In this study, we report on the influence of high pressure on the microstructure evolution of cryomilled nanostructured Al alloy powders during spark plasma sintering (SPS). Our experimental results suggest that the particular mechanism that governs grain growth during SPS depends on the magnitude of the applied pressure. In the case of material consolidated at a high pressure (e.g. 500 MPa), grain coarsening occurs via a combination of thermally activated grain boundary (GB) migration, stress-coupled GB migration and grain rotation-induced grain coalescence. In contrast, in the case of the material consolidated at a low pressure (50 MPa), grain growth occurs primarily via thermally activated GB migration.     

方法影响结果?方法变异的本质、影响及控制

方法变异是由研究方法导致的系统误差.方法变异既可能产生结构层面的影响,也可能产生题目层面的影响;既可能影响单个结构的测量,也可能影响用相同方法研究的多个结构之间的关系,还可能影响用相同方法研究的多个研究之间的关系,进而影响到相关领域的理论建构.在控制方法变异时,可采取过程控制法和统计控制法,最好先用过程控制法.     

The time course of attentional deployment in contextual cueing

The time course of attention is a major characteristic on which different types of attention diverge. In addition to explicit goals and salient stimuli, spatial attention is influenced by past experience. In contextual cueing, behaviorally relevant stimuli are more quickly found when they appear in a spatial context that has previously been encountered than when they appear in a new context. In this study, we investigated the time that it takes for contextual cueing to develop following the onset of search layout cues. In three experiments, participants searched for a T target in an array of Ls. Each array was consistently associated with a single target location. In a testing phase, we manipulated the stimulus onset asynchrony (SOA) between the repeated spatial layout and the search display. Contextual cueing was equivalent for a wide range of SOAs between 0 and 1,000 ms. The lack of an increase in contextual cueing with increasing cue durations suggests that as an implicit learning mechanism, contextual cueing cannot be effectively used until search begins.     

Can You Hear Me Now? The Impact of Voice in an Online Gaming Community

This paper reports the results of a controlled field experiment in which voice communication was introduced into an existing online community (online gaming guilds within the popular game “World of Warcraft”), comparing a mix of voice and text with text only. Quantitative results suggest increases in liking and trust due to the addition of voice, as well as insulation from unexpected negative impacts of text‐only play. The findings are discussed with respect to social capital, cyberbalkanization, and the general computer‐mediated communication literature, with special attention paid to social information processing theory.     

Proactive interference from items previously stored in visual working memory

This study investigates the fate of information that was previously stored in visual working memory but that is no longer needed. Previous research has found inconsistent results, with some showing effective release of irrelevant information and others showing proactive interference. Using change detection tasks of colors or shapes, we show that participants tend to falsely classify a changed item as "no change" if it matches one of the memory items on the preceding trial. The interference is spatially specific: Memory for the preceding trial interferes more if it matches the feature value and the location of a test item than if it does not. Interference results from retaining information in visual working memory, since it is absent when items on the preceding trials are passively viewed, or are attended but not memorized. We conclude that people cannot fully eliminate unwanted visual information from current working memory tasks.     

熠熠生辉的"皮亚杰新形式化理论"——评李其维策划《皮亚杰发生认识论精华译丛》

皮亚杰新形式化理论涉及的是如何把思维机制加以形式化--心理逻辑学--这一特殊问题.本译丛向读者表达了皮亚杰新理论的两大学术贡献:(1)从群-格概念转向"态射-范畴论";(2)从外延取向的外延逻辑转向注重意义蕴涵的内涵逻辑.     

汉语句子阅读理解中的语境效应

采用计算机快速系列视觉呈现技术,以反应时为指标,利用命名法,考察了汉语句子阅读中的语境效应。该研究表明：语境的作用机制是灵活的,它会随语境条件的变化而变化。在启动词与目标词语义联结弱的情况下,如果语境对目标词是一种低干扰,那么各模块之间彼此独立,一个模块不受另一个模块的影响;如果句法关系改变后的语境对目标词形成高干扰,各模块相互作用,不同语境对词汇通达有不同的作用。当启动词与目标词间有较强的语义联结时,语境效应主要来源于词与词之间的联结启动,这时的语境作用机制符合模块化理论;而当启动词与目标词间有较弱的语义联结时,随语境干扰强度的增加,目标词的词汇通达也随之增加,这时的语境作用机制则符合相互作用理论。     

睡眠剥夺影响风险决策的双系统模型探讨

睡眠剥夺是指由于环境或自身原因无法满足正常睡眠时间的情况。大量实证研究发现, 睡眠剥夺会导致个体在风险决策中更倾向于风险寻求, 同时也有研究表明睡眠剥夺会导致个体风险规避, 而目前尚无统一结论。睡眠剥夺从风险感知、风险容忍、风险决策策略三个方面影响了风险决策, 其心理机制可由认知和情绪双路径模型进行解释, 且脑神经生理学研究也提供了相关证据。未来的研究应该进一步关注：(1)现实工作生活中的睡眠不足对风险决策的影响; (2)睡眠剥夺影响风险决策的理论模型建构。