孤独症谱系障碍者视觉定向与视觉搜索的特点及神经机制

定向网络是注意网络的重要组成部分, 主要包括视觉定向与视觉搜索两大任务。对于这两大注意任务, 正常个体在神经机制上存在较大的重叠, 然而, 孤独症个体却表现出截然相反的行为证据。研究者从非社会信息的注意视角发现, 一般而言, 在视觉定向上, 孤独症个体注意转移不存在缺陷, 而注意脱离存在困难, 但该结论仍有争议; 在视觉搜索上, 孤独症个体存在视觉搜索优势, 但该优势发生的阶段及原因仍需进一步探究。未来研究应进一步考察孤独症个体在视觉定向任务中左右视野的不对称性、视觉搜索优势的内在机制及两大注意任务之间的相互关系。     

Attention capacity and task difficulty in visual search

When a visual search task is very difficult (as when a small feature difference defines the target), even detection of a unique element may be substantially slowed by increases in display set size. This has been attributed to the influence of attentional capacity limits. We examined the influence of attentional capacity limits on three kinds of search task: difficult feature search (with a subtle featural difference), difficult conjunction search, and spatial-configuration search. In all 3 tasks, each trial contained sixteen items, divided into two eight-item sets. The two sets were presented either successively or simultaneously. Comparison of accuracy in successive versus simultaneous presentations revealed that attentional capacity limitations are present only in the case of spatial-configuration search. While the other two types of task were inefficient (as reflected in steep search slopes), no capacity limitations were evident. We conclude that the difficulty of a visual search task affects search efficiency but does not necessarily introduce attentional capacity limits.     

The brain's hemispheres and controlled search of the lexicon: evidence from fixated words and pseudowords

Difference between the brain's hemispheres in efficiency of intentional search of the mental lexicon with phonological, orthographic, and semantic strategies was investigated. Letter strings for lexical decision were presented at fixation, with a lateralized distractor to the LVF or RVF. Word results revealed that both hemispheres were capable of using each of the three strategies, but the right hemisphere had better baseline processing of orthography and was better at processing semantics. Pseudoword results supported the right hemisphere advantage for orthography and showed a left hemisphere advantage for phonology and assessment of possible semantic relationships. Taken together, the data support the idea that the right hemisphere uses orthography to make efficient decisions about novelty of an item, while the left engages in grapheme-to-phoneme conversion to test hypotheses about unfamiliar items. The convergence of data with previous research reveals that the procedure, as well as analyses of pseudowords, inform laterality research.     

Toddlers benefit from labeling on an executive function search task

Although labeling improves executive function (EF) performance in children older than 3 years, the results from studies with younger children have been equivocal. In the current study, we assessed performance in a computerized multistep multilocation search task with older 2-year-olds. The correct search location was either (a) not marked by a familiar picture or given a distinct label, (b) marked by a familiar picture but not given a distinct label, (c) marked by a familiar picture and labeled by the experimenter, or (d) marked by a familiar picture and labeled by the participant. The results revealed that accuracy improved across conditions such that children made the fewest errors when they generated the label for the hiding location. These findings support the hierarchical competing systems model, which postulates that improved performance can be explained by more powerful representations that guide search behavior.     

职业乐观对组织承诺、求职行为的影响:有调节的中介模型

职业乐观是影响个体职业适应的重要因素之一。尽管以往文献大多认为职业乐观是有利的,然而职业乐观的个体也会出现求职行为,导致对现有工作的专注程度降低的负面影响。为了探讨职业乐观的双刃剑效应及其边界条件,通过2个时间点问卷调查法对581名企业员工进行调查,结果发现:(1)职业乐观对求职行为和组织承诺均有正向影响;(2)易变职业生涯定向在职业乐观对求职行为影响中起中介作用,工作归属感在职业乐观对组织承诺影响中起中介作用;(3)心理授权在职业乐观对易变职业生涯定向的影响中起负向调节作用,在职业乐观对工作归属感的影响中起正向调节作用。     

童年期心理虐待与忽视对高中生自杀意念的影响：述情障碍的中介作用和寻求意义感的调节作用

为了探讨童年期心理虐待与忽视与自杀意念之间的关系及其作用机制,本研究采用心理虐待与忽视量表、多伦多述情障碍量表、青少年自杀意念量表及生命意义感量表中的寻求意义感分量表对1074名高中生进行调查。结果表明：（1）童年期心理虐待与忽视对自杀意念有正向预测作用,并且能够通过述情障碍的中介作用影响高中生自杀意念;（2）寻求意义感调节了这一中介过程的直接路径和后半段路径,对后半段路径的调节作用存在性别差异。     

Observed Variability and Values Matter: Toward a Better Understanding of Information Search and Decisions from Experience

The search for different options before making a consequential choice is a central aspect of many important decisions, such as mate selection or purchasing a house. Despite its importance, surprisingly little is known about how search and choice are affected by the observed and objective properties of the decision problem. Here, we analyze the effects of two key properties in a binary choice task: the options' observed and objective values, and the variability of payoffs. First, in a large public data set of a binary choice task, we investigate how the observed value and variability relate to decision‐makers' efforts and preferences during search. Furthermore, we test how these properties influence the chance of correctly identifying the objectively maximizing option, and how they affect choice. Second, we designed a novel experiment to systematically analyze the role of the objective difference between the options. We find that a larger objective difference between options increases the chance for correctly identifying the maximizing option, but it does not affect behavior during search and choice. Copyright © 2013 John Wiley & Sons, Ltd.     

小学生在交通情境中的视觉搜索：发展的观点

为探讨小学生在交通情境中的视觉搜索发展特点,研究以一、二、四和六年级小学生,以及成人为被试,采用“找不同”任务和过马路决策眼动任务进行实验。结果发现,一、二年级小学生“找不同”的效率低于成人;一年级小学生冒险及错失过马路比例均较高;小学生的眼跳特征与成人相似,但对兴趣区的关注低于成人;女生错失过马路比例高于男生,视觉搜索水平及搜索策略的性别差异不显著。研究表明,小学生的视觉搜索能力随年龄逐渐提高,但搜索的有效性低于成人,性别分化不明显。     

生命意义的缺失与追寻

生命意义(Meaning in life)指人们对自己生命中的目的、目标的认识和追求,主要包括意义存在(Presence of Meaning)和意义追求(Search for Meaning)两个维度。生命意义缺失(Absence of Meaning)指个体缺乏生活的目标、对自身存在价值和意义感的感知。意义缺失的体验一方面会带来焦虑、抑郁等消极影响,另一方面将激发起个体强烈的重构意义的动机,引导人们进行意义追求。未来研究应增加对生命意义的获取和提升、意义缺失的原因、含义与结构、意义追求的动机和效果的研究。     

Attentional biases to threat in social anxiety disorder: time to focus our attention elsewhere?

Background: Cognitive models propose that attentional biases to threat contribute to the maintenance of social anxiety disorder (SAD). However, the specific characteristics of such biases are still object to debate.

Objectives: The current study aimed to disentangle effects of trait and state social anxiety on attention allocation towards social stimuli.

Methods: Participants with SAD (n?=?67) and healthy controls (n?=?62) completed three visual search tasks while their eye movements were recorded. Half of the participants in each group were randomly assigned to a state anxiety induction.

Results: Contrary to our predictions, neither trait nor state social anxiety was associated with a facilitated attention to or a delayed disengagement from threat. However, participants with SAD did show reduced fixation durations for threatening stimuli, indicating an avoidance of threat. Induction of state anxiety led to an increased distractibility by threat.

Conclusions: We suggest that attention allocation in SAD is characterized by an avoidant rather than a vigilant attentional bias. Accordingly, our results contradict previous results that associate SAD with facilitated attention to threat and existing approaches to modify attentional biases, that aim to decrease attention towards threatening stimuli.