Blind justice: Fairness to groups and the do-no-harm principle

People are reluctant to harm some people in order to help others, even when the harm is less than the forgone help (the harm resulting from not acting). The present studies use hypothetical scenarios to argue that these judgments go against what the subjects themselves would take to be the best overall outcome. When the outcomes in question are income gains and losses for two groups of farmers, subjects judge the harm they would not impose through their action to be smaller than the harm they would impose through inaction. Some subjects refuse to reduce cure rates for one group of AIDS patients in order to increase cure rates more for another group, even when group membership was unknowable to anyone, so that, from each patient's point of view, the change would increase the probability of cure. Likewise, they resisted a vaccine that reduced overall mortality in one group but increased deaths from side effects in another group, even when, again, group membership was unknowable. Some people apply a do-no-harm principle to groups without apparent understanding of how such a principle might be justified in terms of its consequences. The capacity for such judgments makes them vulnerable to learning principles that have no justification at all.     

When is the Wilcoxon–Mann–Whitney procedure a test of location? Implications for effect-size measures

The Wilcoxon–Mann–Whitney procedure is invariant under monotone transformations but its use as a test of location or shift is said not to be so. It tests location only under the shift model, the assumption of parallel cumulative distribution functions (cdfs). We show that infinitely many monotone transformations of the measured variable produce parallel cdfs, so long as the original cdfs intersect nowhere or everywhere. Thus there are infinitely many effect sizes measured as shifts of medians, invalidating the notion that there is one true shift parameter and thereby rendering any single estimate dubious. Measuring effect size using the probability of superiority alleviates this difficulty.     

Evidence for altered configural body processing in women at risk of disorders characterized by body image disturbance

Two studies were conducted to assess appearance-related visual processing mechanisms in populations at risk of disorders characterized by body image disturbance. Using inverted stimuli, Experiment 1 assessed visual processing mechanisms associated with body, face, and house viewing in adolescents. Experiment 2 applied the same protocol to assess appearance-related configural processing in high- and low-risk adolescent women, and women recovering from disorders characterized by body image disturbance. Experiment 1 found evidence for typical configural face and body processing, although adolescent women reported higher levels of body image concern (BIC) and self-objectified to a greater extent than adolescent men. In Experiment 2, typical body inversion effects were seen in the low-risk group, whilst there was some evidence to suggest a disruption to the configural processing of body stimuli in high-risk adolescents and in women recovering from body image disorders. Women in recovery were also quicker to respond to all stimuli, whilst high-risk adolescents took longer to respond to bodies than to other stimuli. Configural face processing was intact in all groups, and effects did not directly relate to BIC or self-objectification. These findings have implications for future research looking to inform early interventions and treatment, suggesting that there could be a tendency to visually process individual body parts at the expense of the whole-body form in women at risk of developing body image disorders, as well as those in recovery.     

Misunderstandings and omissions in textbook accounts of effect sizes

There have been frequent attempts in psychology to reduce the reliance on null hypothesis significance testing (NHST) as the criterion for establishing the importance of results. Many authorities now recommend the reporting of effect sizes (ESs) as a supplement or alternative to NHST. However, there is extensive specialist literature highlighting problems associated with the use and interpretation of ESs. A review of the coverage of ESs in over 100 textbooks on statistical analysis in behavioural science revealed widespread neglect of ESs and the relevant critical issues that have widespread coverage in the more specialist literature. For example, many textbooks claim that ESs should be interpreted as a simple measure of the practical real-world importance of a result despite the fact that ESs are profoundly influenced by features of design and analysis strategy. We seek to highlight areas of misunderstanding about ESs found in the pedagogical literature in the light of the more specialist literature and make recommendations to researchers for the appropriate use and interpretation of ESs. This is critical as statistics textbooks have a crucial role in the education of researchers.     

视觉工作记忆回溯线索效应的产生机制：认知阶段分离

以往研究关于视觉工作记忆回溯线索效应的产生机制主要存在5种假设, 目前依然存在争议。本研究通过改进前人研究实验范式, 采用包含内源性回溯线索的颜色回忆报告范式, 进一步对这5种假设进行检验。在实验1中, 我们调控了线索与探测阵列之间的时间间隔, 发现不同时间间隔不影响无线索条件的行为表现, 而在正常线索条件中被试的记忆精度以及能记住的项目数量均优于无线索条件; 在实验2中, 我们对回溯线索伴随的干扰刺激类型进行控制, 结果显示, 在不同条件下记忆精度不存在差别, 但当回溯线索伴随干扰刺激呈现时, 被试能记住的项目数量会被降低, 降低程度受干扰刺激的类型调制; 在实验3中, 我们对伴随回溯线索的干扰刺激的呈现时间进行控制, 发现虽然回溯线索效应仍然存在, 但干扰刺激的呈现时间不会影响效应程度。研究结果表明, 回溯线索的出现使得被试能够在决策加工前完成内部注意资源的再分配, 从而避免了同时进行这两种认知加工与记忆表征维持本身竞争认知资源。本研究为认知阶段分离假设提供了支持证据, 对解决回溯线索效应产生机制的争议以及理解内部注意与视觉工作记忆的关系有重要意义。     

群体认同对群际敏感效应及其行为表现的影响

通过实验研究了群际互动中个体对不同来源身份的消极群体评价的情绪反应及群体认同的调节作用, 并从情绪-行为反应的连续性视角探索群际敏感效应的行为表现及内在机制。结果发现:(1)相比内群体的消极群体评价, 外群体的消极群体评价更能引起消极情绪反应; (2)群体认同对群际敏感效应起调节作用, 高群体认同者对来自外群体消极评价的情绪反应更加负面, 而低群体认同者这种趋势并不明显; (3)高群体认同者在经历外群体的消极群体评价后会表现出更多的内群体积极行为, 且消极情绪反应对此起中介作用。研究扩展了群际敏感效应的适用范围, 并为探讨其内部机制和后续影响提供了新的研究思路。     

语言熟练度对Stroop效应的影响——不平衡双语者的任务态fMRI研究

目的:探讨语言熟练度对Stroop效应的影响及其背后的脑机制。材料与方法:17位被试参与本研究。被试母语为汉语,第二语言为英语。在被试完成中英文的stroop色字的任务过程中对被试进行fMRI扫描。结果:在色字相一致的条件下,中文任务与英文任务相比,双侧背侧枕叶及右侧背外侧前额叶有更强的激活; 反向比较,双侧腹侧枕叶有更强的激活。在色字不一致的条件下,中文任务与英文任务相比,双侧背外侧前额叶、右侧枕下回有更强的激活; 反向比较,并无显著激活的脑区。此外,中文Stroop效应引起左侧额下回显著的激活。英文Stroop效应中,左侧额下回无显著激活。结论:结合前人研究,我们得出,语言熟练度影响了对注意控制有重要作用的背外侧前额叶以及与反应抑制有关的左侧额下回在Stroop任务中的参与程度,进而影响了Stroop任务的表现     

Cognitive complexity of social images revealed by Jewish Israeli adolescents relating to drawings of Jews and Arabs

The present study examined age‐related differences among Israeli youth regarding the complexity of their mental images of Jews and Arabs, two groups that are adversaries in the Middle East conflict. The participants, 494 Jewish children and adolescents ranging from 8–16 years old each, drew two human figures, one Jewish and one Arab, and then attributed a forename and a profession to each drawn image. Four complexity variables were scored as follows: image complexity (number of items included in the figure), embellishments (number of items added to the drawing and in the space around the figure), image name, and image profession. Overall, participants depicted members of their in‐group as more complex. However, early adolescence was found to be a critical age at which differences emerged. The findings suggest that introducing complexity to social representations in early adolescence may facilitate prevention of negative associations related to outgroups and enhance intervention to reduce stereotypes, prejudice, and racism.     

The relationship between endowment and ownership effects in memory across cultures

An object one owns is typically more highly valued than an equivalent object owned by another person. This endowment effect has been attributed to the aversion of loss of one’s possessions (through selling), or the added value of an item due to self-association (through owning). To date, investigation of these mechanisms has been hampered by the between-subjects methodology traditionally employed to measure endowment. Over two experiments, we report a novel within-subjects method for measuring an endowment bias. In these studies, Western participants showed enhanced valuation of owned items, whereas East-Asian participants did not. This endowment bias also correlated with the ownership effect in memory (a measure of self-referential processing) in Western, but not East-Asian participants. Our results suggest that the endowment effect is partly predicated on the same factors that influence the ownership effect and that this commonality is likely linked to conceptions of ownership specifically, and self-concept more generally.     

Aging drivers and post delineated express lanes: Threading the needle at 70 miles per hour

Post-delineated express lanes represent a combination of driving complexities that are particularly difficult for older drivers to navigate. The narrow geometry and high speeds that are common to this treatment reflect a critical test for drivers whose depth perception, contrast sensitivity, and visual processing speed are reduced. The present study was designed to empirically examine the effects of age and color of express lane delineators on driver behavior. Three groups of participants (aged 18–39, 40–64, and 65 + years old) were required to complete a series of simulated driving scenarios consisting of combinations of single and dual lane configurations, with speed and lane position measured at the beginning and midpoint of each express lane. All drivers were pre-screened on various visual functioning abilities. Drivers in the 65 and older group show significant age-related declines in depth perception, contrast sensitivity, and phoria which were subsequently correlated with a wide range of driving measures including deceleration rate, brake time, jerk, speed, and lane position. Age related perceptual declines were statistically correlated with slower driving speed and wider lane deviations, including a statistically significant increase in the number of excursions beyond the typical 12-foot lane width. Based on these findings, the behavior of senior drivers was identified as a distinct design condition that should govern the design of high-speed, narrow geometric conditions. This age group requires wider lane widths, particularly at the beginning of single-lane post delimited sections, wider buffer areas around the post markers, and dual lane configurations wherever possible.