Electrophysiological evidence of central interference in the control of visuospatial attention

Visuospatial attention can be deployed to different locations in space without movement of the eyes. A large body of human electrophysiological studies reveals enhanced sensory-perceptual responses to stimuli that appear at an attended location. However, it is not clear that the mechanisms that underlie visuospatial attention are under the control of attention mechanisms that limit central processing in multiple-task situations. We investigated this question by incorporating a visual task that required the deployment of visuospatial attention as the second task of psychological refractory period (PRP) dual-task paradigms. The N2pc component of the event-related potential was used as an electrophysiological index of the moment-by-moment deployment of visuospatial attention to monitor when and where observers were attending while they performed concurrent central processing known to cause the PRP effect. Electrophysiological evidence shows that central processing interfered with the N2pc, suggesting that visuospatial attention is under the control of capacity-limited central mechanisms.     

How are Strouhal number, drag, and efficiency adjusted in high level underwater monofin-swimming?

Strouhal number (St) corresponds to a wake parameter based on the tail kinematics of swimming animals according to St=A.f/U, where f is the stroke frequency, A is the fin-beat peak-to-peak amplitude, and U is the forward speed. St number is a trade-off between amplitude and frequency that generates a forward velocity. This parameter may therefore be affected by swimming technique, which can be evaluated through active drag (AD) and Froude efficiency (eta(F)). The aim of our study was therefore to (1) investigate the range of AD and eta(F) values for high level monofin-swimmers, (2) explore the range of St numbers, and (3) examine to what extent this latter non-dimensional parameter may affect AD and eta(F). To this end, experiments have been conducted on 12 international level monofin-swimmers. St number, eta(F) (calculated according to the elongated-body theory), and AD (computed with velocity perturbation method) were calculated at the same time for an underwater fin-swimming trial, at maximal speed. Lowest values of St numbers (St=0.34) corresponded to fin-swimmers with highest velocities (R=-.77, p<.05), highest efficiencies (R=-.86, p<.001), and lowest active drag (R=.91, p<.001). On the one hand, AD was increased with vertical motion of the fin (R=.84, p<.001), which increased cross-sectional area (R=.78, p<.05). On the other hand, efficiencies showed a tendency to peak at eta(F)=0.82 in a narrow range of St numbers close to 0.4. This St range corresponded to the upper limit of the 0.25-0.4 range usually claimed for maximum efficiency of marine and flying animals. Such results suggest that increasing efficiency and reducing drag improves performance per se (regardless how these parameters are related with St number).     

基于元胞自动机的濒危植物明党参种群数量动态研究

根据3年来积累的和峨参野外实验数据,利用元胞自动机模型在计算机上模拟了濒危植物明党参(Changium smyrnioides)的种群生长动态,并选取同科的峨参(Anthriscus sylvestris)作为对照种进行比较分析。模拟结果显示,两个物种在种群中的个体数量均随生殖率m和可利用生境比率h的增大而增加,当生殖率大于0.6732时明党参种群才可在模拟时间尺度上(100年)保持不衰退;峨参生殖率的变化则不会使种群衰退,当m>9.15时,种群密度就不再增加。明党参的最小生境需求值小于峨参。明党参在h大于0.7%时,种群密度不再增加,即明党参最多只能利用生境的0.4%,峨参则可占据生境中位置的81.9%。综合分析模拟参数和结论,我们认为:明党参偏向于K策略,峨参偏向于r策略。本文相关资料对于确定明党参相应的保护措施有重要参考价值。研究元胞自动机在生态学上的初步模拟可以为将来进行更加深入的研究奠定基础。     

Simultaneous completions of modal and amodal figures: Visual evoked potentials reveal asymmetrical interference effects

Modal and amodal completion processes are thought to affect the emergence and the potency of each other. To see whether one dominates over the other, we measured the Npd, that is, the negativity of visual-evoked potentials whose amplitude increases with perceptual difficulty. In the first experiment, the Npds to illusory (modal) squares and diamonds placed over amodal diamonds and squares, respectively, were found to be greater when targets were the amodal figures than when targets were the modal figures, thus suggesting that modal figures created more interference. A second experiment showed that greater Npds were specific to interference and not to the greater difficulty at focusing on amodal figures rather than on modal figures. A third experiment showed that the interference also occurs with real figures in replacement of modal ones. Overall, the results suggest a certain dominance of modal completion over amodal completion when both occur in the same display.     

Why do people behave immorally when drunk?

Alcohol intoxication is a major source of antisocial behavior in our society, strongly implicated in various forms of interpersonal aggression. Yet, moral philosophers have paid surprisingly little attention to the literature on alcohol and its effects. In part, this is because philosophers who have adopted a more empirically informed approach to moral psychology have gravitated toward moral sentimentalism, while the literature on alcohol intoxication fits very poorly with the sentimentalist account. Most contemporary research on the psychological effects of alcohol is focused upon variants of the “disinhibition” theory, which suggests that alcohol does not provoke any specific affect, it merely weakens executive control. This research, we argue, lends support to a deontic moral psychology, which identifies our ability to suppress behavioral impulses as a central feature of moral agency.     

On the role of intervening distractors in the attentional blink

The attentional blink (AB) refers to the decline in accurate report for a second target (T2) when presented within about 500 ms of a first target (T1) embedded in a rapid serial visual presentation stream of distractors. It is debated whether the distractors presented shortly after T1 cause the AB directly, as is proposed by distractor-based models, or can modulate its amplitude only indirectly by increasing T1 difficulty, as is proposed by capacity-based models. To investigate this issue, an intervening distractor was presented at lag 1 (T1 + 1), at lag 2 (T1 + 2), or at neither of these two lags (no distractor). T2 was presented at either lag 3 or 9. An AB was observed even in the absence of intervening distractors, indicating that distractors are not necessary to produce an AB. Nonetheless, the T1 + 2 distractor did modulate the AB directly, without influencing T1 performance. Neither theory can fully account for the results but can do so given some modifications.     

Achievement Goals in Educational Contexts: A Social Psychology Perspective

Research on achievement goals usually defines mastery goals as the desire to acquire knowledge, and performance goals as the desire to outperform (or not to underperform) others. Educational contexts are most of the time social contexts, involving various persons and groups, of various hierarchical positions, and various cultural and ideological contexts. Surprisingly, most research in the achievement goal field has been conducted at an individual level of analysis. In the present paper, we will review the social consequences and antecedents of goal endorsement. This research indicates that goals strongly affect the way one behaves with co‐learners. Moreover, it suggests that more than merely individual dispositions, goals reflect the social relation students have with other persons, institutions, and with the society to which they belong. We conclude this paper by setting an agenda for future achievement goal research.     

论医学人文教育视野中的美学教育

基于医学人文教育的视野,阐述了对医学生进行美学教育的重大意义.探讨了对医学生进行美学教育的若干重要原则,医学人文教育视野中的美学教育应引导医学生树立生命意识、反省意识、首创意识、认识论意义上的自由意识和本体论意义上的自由意识,从而实现医学生自由而全面的发展.     

公立医院补偿机制改革之政府补偿方式探讨

从公立医疗服务准公共产品特性和医疗服务的性质两个方面,强调了政府对公立医院补偿的必要性和合理性,并指出了政府补偿中存在财政补偿不足、缺乏补偿标准、监管不力等问题.同时,针对政府补偿现状提出了加大政府对公立医院的投入;设计科学合理的公立医院财政补偿制度;加强对公立医院财政投入资金的监管等政策建议.     

A normative perspective on the linguistic intergroup bias: How intragroup approval of ingroup members who use the linguistic intergroup bias perpetuates explicit intergroup bias

The present research examined from a normative perspective how intragroup normative processes regulate the consequences of the linguistic intergroup bias (LIB). Results of three studies supported our hypothesis that intragroup approval of an ingroup member who uses the LIB plays a key role in perpetuating pro-ingroup bias. In Study 1, ingroup members who used pro-ingroup (vs. pro-outgroup) LIB elicited more intragroup approval and this effect was mediated by the perception of the speaker as being biased in favor of the ingroup. In Studies 2 and 3, intragroup approval (vs. disapproval) of an ingroup member who used the LIB enhanced the expression of pro-ingroup bias. By providing the first demonstration of how the LIB relates to intragroup normative processes, our studies highlight a new path by which the LIB helps perpetuate intergroup bias.