The roles of dispositional optimism and pessimism in hiv disease progression

Relationships between dispositional optimism and pessimism and the course of HIV infection, determined by changes in viral load and CD4 counts, were studied in a longitudinal cohort of 412 patients on antiretroviral therapy (ART). Multiple regression analyses controlling for baseline levels of disease status, ethnicity, and depressive symptoms demonstrated that higher pessimism at baseline was associated with higher viral load at follow-up (average of 18 months later). Optimism at baseline had a curvilinear relationship with CD4 counts at follow-up. Moderate levels of optimism at baseline predicted the highest CD4 counts at follow-up. Although optimism and pessimism were associated with specific health behaviors (e.g., ART adherence, cigarette use, drug use, dietary practices), none of these behaviors mediated the optimism/pessimism effects. The biologic and behavioral mediators of associations of personality variables with the course of treated HIV infection deserve continued investigation.     

Perceptual load does not modulate auditory distractor processing

In vision, it is well established that the perceptual load of a relevant task determines the extent to which irrelevant distractors are processed. Much less research has addressed the effects of perceptual load within hearing. Here, we provide an extensive test using two different perceptual load manipulations, measuring distractor processing through response competition and awareness report. Across four experiments, we consistently failed to find support for the role of perceptual load in auditory selective attention. We therefore propose that the auditory system – although able to selectively focus processing on a relevant stream of sounds – is likely to have surplus capacity to process auditory information from other streams, regardless of the perceptual load in the attended stream. This accords well with the notion of the auditory modality acting as an ‘early-warning’ system as detection of changes in the auditory scene is crucial even when the perceptual demands of the relevant task are high.     

Truth table task: Working memory load,latencies, and perceived relevance

The aim of the present study is to uncover the relation between cognitive ability and the answer patterns yielded by the truth table task. According to the Classical Mental Models Theory, people with high working memory capacity answer according to two-valued or “logical” answer patterns. The Suppositional Theory and the Revised Mental Models Theory predict that the answer patterns given by the most intelligent ones are three-valued or “defective”. Correlations are examined, and in three experiments it is tested with a dual task paradigm whether a differential working memory load alters participants' answer patterns. A positive correlation is observed between cognitive ability and three-valued answer patterns, but no effect of the working memory load manipulation is revealed. With an inspection of the classification times we shed light on the processes underlying truth table judgements. We conclude that the Revised Mental Models Theory provides the best account for our results.     

How Cognitive Load Influences Speakers' Choice of Referring Expressions

We report on two experiments investigating the effect of an increased cognitive load for speakers on the choice of referring expressions. Speakers produced story continuations to addressees, in which they referred to characters that were either salient or non‐salient in the discourse. In Experiment 1, referents that were salient for the speaker were non‐salient for the addressee, and vice versa. In Experiment 2, all discourse information was shared between speaker and addressee. Cognitive load was manipulated by the presence or absence of a secondary task for the speaker. The results show that speakers under load are more likely to produce pronouns, at least when referring to less salient referents. We take this finding as evidence that speakers under load have more difficulties taking discourse salience into account, resulting in the use of expressions that are more economical for themselves.     

Challenging perceptual tasks require more attention: The influence of task difficulty on the N1 effect of temporal orienting

Both filter and resource models of attention suggest an influence of task difficulty on the size of early attention effects. As for temporal orienting, the idea that early effects are modulated by task difficulty has not been tested directly, so far. To fill this empirical gap, the present study used an auditory temporal-orienting task, in which two differently pitched pure tones served as targets. To manipulate perceptual difficulty, the pitch difference between the targets was either small or large. Temporal orienting enhanced the N1 component of the auditory event-related potential. This early, sensory effect tended to be larger in the more difficult condition, particularly over the frontal scalp. Notably, increasing task difficulty affected predominantly the processing of attended stimuli. Hence, temporal orienting may operate by increasing processing resources or gain settings for the attended time point – rather than by withdrawing resources from the unattended time point.     

贫困损害儿童执行功能的作用机制

贫困儿童往往表现出较差的执行功能,贫困的长期危害甚至持续到成人期。为揭示贫困与儿童执行功能弱化之间的作用机制,已有研究分别从行为、生理和脑层面开展了探索。本文沿着行为-生理-脑的内在联系与思路,系统地梳理了有关单一风险、累积风险、剥夺性风险、适应负荷以及前额叶结构和功能等内在机制的最新研究。最后提出未来研究可以关注贫困对儿童执行功能某些成分的塑造、聚焦剥夺性风险因素的作用机制、开展适应负荷生理机制和相关脑区激活的认知神经机制等方面的研究,以构建行为-生理-脑的整合框架,进一步拓展未来研究领域。     

Assessing lifetime stressor exposure in sport performers: Associations with trait stress appraisals,health, well-being,and performance

Research has found that greater lifetime stressor exposure increases the risk for mental and physical health problems. Despite this, few studies have examined how stressors occurring over the entire lifespan affect sport performers’ health, well-being, and performance, partly due to the difficulty of assessing lifetime stressor exposure. To address this issue, we developed a sport-specific stress assessment module (Sport SAM) for the Stress and Adversity Inventory (STRAIN) and then analyzed the instrument’s usability, acceptability, validity, and test-retest reliability. Furthermore, we examined whether trait-like tendencies to appraise stressful situations as a challenge or threat mediated the association between lifetime stressor exposure and health, well-being, and performance. Participants were 395 sport performers (M_age = 22.50 years, SD = 5.33) who completed an online survey. Results revealed that the Sport SAM demonstrated good usability and acceptability, good concurrent validity in relation to the Adult STRAIN (rs = 0.23 to 0.29), and very good test-retest reliability (r_icc = 0.87 to 0.89). Furthermore, the Sport SAM was significantly associated with symptoms of depression (β = 0.21 to 0.24, ps ≤ .001) and anxiety (β = 0.13 to 0.19, ps ≤ .012), and general physical (β = 0.24 to 0.27, ps = ≤ 0.001) and mental (β = 0.23 to 0.32, p ≤ .001) health complaints. Finally, we found that associations between total lifetime non-sport and sport-specific stressor severity and health were mediated by trait stress appraisals. Consequently, these findings may help practitioners better identify sport performers who are at risk of developing stress-related health problems.     

工作记忆中央执行成分对估算表现的影响

工作记忆中央执行成分在计算加工的诸多过程中发挥重要影响。以82名大学生为被试,采用双任务实验范式考察工作记忆中央执行成分对估算表现的影响。结果发现：1）估算过程需要中央执行成分的参与,增加中央执行成分负荷会导致估算准确率下降;2）无论是否增加中央执行负荷,问题大小效应在估算中均不明显;3）乘法个位数大小顺序会影响估算值的准确性,在有中央执行负荷时数字顺序效应明显。     

On the automaticity of pure perceptual sequence learning

We investigated the automaticity of implicit sequence learning by varying perceptual load in a pure perceptual sequence learning paradigm. Participants responded to the randomly changing identity of a target, while the irrelevant target location was structured. In Experiment 1, the target was presented under low or high perceptual load during training, whereas testing occurred without load. Unexpectedly, no sequence learning was observed. In Experiment 2, perceptual load was introduced during the test phase to determine whether load is required to express perceptual knowledge. Learning itself was unaffected by visuospatial demands, but more learning was expressed under high load test conditions. In Experiment 3, we demonstrated that perceptual load is not required for the acquisition of perceptual sequence knowledge. These findings suggest that perceptual load does not mediate the perceptual sequence learning process itself, supporting the automaticity of implicit learning, but is mandatory for the expression of pure perceptual sequence knowledge.     

不同认知成分在图形推理测验项目难度预测中的作用

理解项目难度变异的来源是实现计算机自动化项目生成的第一步。通过文献综述, 总结出影响图形推理测验项目难度的四个方面的因素, 再通过操控构图元素熟悉性、属性的抽象性、知觉组织的和谐性以及规则类型与数目这些因素, 编制8套图形推理测验, 共包含112个与高级瑞文推理类似的项目。采用铆测验等值设计, 在每套测验中嵌入10个高级瑞文推理测验项目为铆题, 通过网络施测于6323名被试。使用BILOG MG估算项目参数, 并使用IRTEQ进行测验等值, 将后七套测验上所有项目的项目参数都转换到第一套测验的单位系统上。以项目难度为因变量, 项目题干特征变量为预测变量进行回归分析, 结果发现这四个因素均对项目难度有显著预测作用。优势分析的结果显示记忆负荷(即规则类型与数目的组合)是项目难度的最重要的预测变量, 其他依次为属性的抽象性、知觉组织的和谐性和构图元素熟悉性。