The CIOMS view on the use of placebo in clinical trials

Based on worldwide consultations with experts in science and ethics the revised CIOMS 2002 International Ethical Guidelines for Biomedical Research Involving Human Subjects provide guidance on when the use of placebo as a comparator in clinical research is ethically acceptable. The article reviews the main points of the CIOMS Guidelines and commentaries including the use of placebo in situations where the best current method is available and the relation of placebo to established effective intervention. It discusses the use of placebo in externally sponsored research in low-resource countries and requirements for informed consent related to placebo studies. An earlier version of this paper was presented at an international conference, “Placebo: Its Action and Place in Health Research Today,” held in Warsaw, Poland on 12–13 April, 2003.     

Perceived stress,life events,dysfunctional attitudes,and depression in adolescent psychiatric inpatients

Hewitt, Flett, and Mosher (1992) examined the factor structure of the Perceived Stress Scale (PSS) and its relation to depression in adult psychiatric patients. This study sought to replicate and extend their findings, using a sample of 203 adolescent psychiatric inpatients. All patients admitted to the adolescent unit in a psychiatric hospital over a 3-year period were administered the PSS, as well as measures of depression, life events, dysfunctional attitudes, and intellectual abilities. Consistent with Hewittet al., two factors were found in the PSS, reflecting perceived distress and perceived coping ability. Regression analyses indicated that, for males, both factors account for independent variance in depression, whereas for females, only the distress factor is related to depression. In addition, for both male and female, dysfunctional attitudes account for significant variance in depression in addition to PSS, but negative life events do not. None of the variables were related to intellectual abilities. Implications for clinical assessment and intervention are discussed.     

Perceived social support,coping, and symptoms of distress in American and Spanish students

Abstract

The aim of this study was to test whether coping responses mediated the influence of perceived social support on symptoms of anxiety/depression, social withdrawal, and aggressive behavior in American (N=349) and Spanish students (N=437). Participants completed measures of perceived support, social stress, coping, and distress. Coping partially mediated relations between perceived support and distress, with coping mediation most evident in individuals facing high levels of social stress. Decreased use of disengagement coping by individuals with high perceived support appears to partially explain the protective value of perceived social support. Multiple group covariance structure analysis showed that models linking perceived support, coping, and distress were very similar across cultures, suggesting that the mechanisms underlying decreased risk for individuals with high perceived support may be relatively independent of cultural context, and that interventions designed to increase perceived support and decrease disengagement could be appropriate in both cultures.     

The attentional window configures to object and surface boundaries

Attention can select items based on location or features. Belopolsky and colleagues posited the attentional window hypothesis, which theorized that spatial and featural selection interact such that featural selection occurs within a “window” of spatial selection. Kerzel and colleagues recently found that the attentional window can take complex shapes, but cannot configure around non-contiguous locations. The current experiments investigated whether perceptual grouping cues, which produce perceptual objects or surfaces, enable the attentional window to configure around non-contiguous locations. Using the additional singleton paradigm, we reasoned that observers (1) would be slowed by a colour singleton distractor that appears within the observers’ attentional window and (2) would be unaffected by distractors that do not appear within the attentional window. In separate blocks of trials, a target appeared upon one of two objects. Observers were cued to the relevant surface, and we asked if responses were affected by distractors on the cued task-relevant surface, and on the uncued irrelevant surface. Colour singleton distractors slowed responses when they appeared on the cued surface, even when those locations were non-contiguous locations. Distractors on the irrelevant surface did not affect responses. The results support a highly adaptable attentional window that is configurable to the surfaces and boundaries established by intermediate-level vision.     

特殊教育教师工作要求与职业倦怠：心理控制源的中介作用

目的：考察心理控制源在特殊教育教师工作要求与职业倦怠间的中介作用.方法：整群抽取252名特殊教育教师接受量表测量.结果：（1）工作要求与职业倦怠存在显著的性别差异;（2）相关分析表明,工作要求、职业倦怠与心理控制源之间呈显著相关;（3）心理控制源在工作要求与职业倦怠间起着中介作用;独立的中介效应检验中,三种控制源（内控性、有势力的他人、机遇）在工作要求与职业倦怠间都起着部分中介作用;综合模型中,工作要求主要通过有势力的他人这一中介与职业倦怠产生联系,同时也与职业倦怠间存在直接效应.结论：心理控制源是工作要求预测职业倦怠的部分中介因素.     

为什么贫困会削弱决策能力？三种心理学解释

贫困削弱决策能力的心理学解释有三种基本视角: 注意力损耗论认为个体的注意力易集中于资源匮乏的领域而忽略其他, 意志力损耗论认为抵制外在诱惑会消耗其意志力, 认知控制损耗论认为贫困者的经济决策在难度上高于其他决策。这三种有限心理资源的损耗会削弱贫困者的认知表现而诱发非理性决策。后续研究应注意澄清三大机制之间的区别, 分析贫困损耗认知的结果是否具有可逆性, 同时就已有结果的跨文化适用性做出验证。     

Inter-limb coordination and control in boys with and without DCD in ball catching

The purpose of the study was to examine the nature of inter-limb coordination and control, exhibited by ten boys with (M = 10.5 years, SD = 1.0) and without Developmental Coordination Disorder (DCD), in a ball catching task across different ball speeds. In line with the predictions of coordinated structure theory boys who were typically developing preserved strong and effective temporal relations when catching balls in baseline and fast conditions. Boys with DCD exhibited temporal symmetry in baseline but not in fast attempts, where the decoupling was uniformed across the group, coinciding with failures on ≥ 50% of the attempts. In terms of stability, no differences in intra-individual variability were observed between the groups. The analysis of spatial and temporal adaptations showed that boys who were typically developing, in essence, covered the same “ground” by decreasing their movement time. The opposite was true for boys with DCD who contacted the ball closer to the body, while failing to adapt the velocity of their hands. Taken together, both groups exhibited strong and stable coordinative relations, in a steady-state but not in a fast condition, where all boys with DCD failed to preserve the desired symmetry. This decoupling also coincided with different and less effective spatio-temporal adaptations at the effector level. Thus, it appears that movement control, hence flexibility of their synergistic relations, represents a movement limiter for boys with DCD who exhibit specific balls skills issues, at inter-limb level of organization. It should be noted, however, that large intra-group variance observed across some variables warrants caution when interpreting the aggregate data.     

Adapting to an initial self-regulatory task cancels the ego depletion effect

The resource-based model of self-regulation provides a pessimistic view of self-regulation that people are destined to lose their self-control after having engaged in any act of self-regulation because these acts deplete the limited resource that people need for successful self-regulation. The cognitive control theory, however, offers an alternative explanation and suggests that the depletion effect reflects switch costs between different cognitive control processes recruited to deal with demanding tasks. This account implies that the depletion effect will not occur once people have had the opportunity to adapt to the self-regulatory task initially engaged in. Consistent with this idea, the present study showed that engaging in a demanding task led to performance deficits on a subsequent self-regulatory task (i.e. the depletion effect) only when the initial demanding task was relatively short but not when it was long enough for participants to adapt. Our results were unrelated to self-efficacy, mood, and motivation.     

Cognitive biases in aggressive drivers: Does illusion of control drive us off the road?

Anger has been shown to be a motivating factor in aggression and it is widely accepted that driving anger may lead to aggressive driving. However, the link between anger and aggressive driving is likely to be mediated by drivers’ pre-existing cognitive biases and the subsequent situational evaluations made. This study investigated the extent to which optimism bias, illusion of control beliefs and driver anger predict self-reported hostile driving behaviours. A total of 220 licensed drivers (106 men; 114 women) completed a self-report questionnaire measuring trait driving anger, optimism bias, illusion of control and driving behaviour. Structural Equation Modelling showed that trait driving anger and illusion of control beliefs account for 37% of the variance in hostile driving behaviour scores. Optimism biases were unrelated to hostile driving behaviours. Thus, driving anger propensities and feelings of control over the situation, but not a general tendency to underestimate the likelihood of adverse outcomes, predict aggressive driving.     

自上而下的注意控制定势在注意捕获中的作用

采用经典前线索范式的变式, 通过100%有效的提示考察了自上而下的注意控制定势在注意捕获中的作用。实验1要求被试在整个实验中只搜索一个固定颜色的目标, 但是通过在每个试次前对目标进行提示加强注意控制定势的强度。实验2通过在每个试次中变化要搜索的目标颜色使被试必须建立两个更强的注意控制定势。实验结果一致表明和目标颜色相匹配的线索捕获了注意, 而和目标颜色无关的线索被抑制; 实验2的捕获效应和抑制效应都显著大于实验1; 对无关冲突线索和无关中性线索的注意抑制效应没有差异, 抑制效应显著小于捕获效应。研究表明自上而下的注意控制定势通过把注意从和目标不匹配的特征位置转移发挥作用, 支持注意转移假说; 对匹配线索的捕获和对无关线索的抑制运用了同一加工系统, 抑制作为捕获的附加产品出现, 两者都可以作为注意捕获的指标。