Reliability and plasticity of response inhibition and interference control

This study investigated the internal reliability, temporal stability and plasticity of commonly used measures of inhibition-related functions. Stop-signal, go/no-go, antisaccade, Simon, Eriksen flanker, Stroop and Continuous Performance tasks were administered twice to 23 healthy participants over a period of approximately 11 weeks in order to assess test–retest correlations, internal consistency (Cronbach’s alpha), and systematic between as well as within session performance changes. Most of the inhibition-related measures showed good test–retest reliabilities and internal consistencies, with the exception of the stop-signal reaction time measure, which showed poor reliability. Generally no systematic performance changes were observed across the two assessments with the exception of four variables of the Eriksen flanker, Simon and Stroop task which showed reduced variability of reaction time and an improvement in the response time for incongruent trials at second assessment. Predominantly stable performance within one test session was shown for most measures. Overall, these results are informative for studies with designs requiring temporally stable parameters e.g. genetic or longitudinal treatment studies.     

Two facets of cognitive control in analogical mapping: The role of semantic interference resolution andgoal-driven structure selection

The study used scene analogies to investigate two component processes of analogical thinking: resolution of semantic interference, which emerges when the proper mapping between analogically matching objects is incoherent with their categorical features (e.g., stereotypical functions), and goal-driven selection of the key relational structure, by directing attention to the most promising objects which constitute that structure among many other candidate objects. We manipulated interference by placing in corresponding scenes the objects from one category in different relational roles. Selection was loaded by including additional, relationally irrelevant objects in a scene. We also manipulated relational complexity and the presence of salient objects (people) in relations. Increased load on both interference resolution and selection decreased the accuracy of analogical mapping, but these factors did not interact. Moreover, the factors yielded opposite patterns of interaction with relational complexity. Finally, salience eased selection, but tended to negatively influence interference resolution. In summary, inference resolution and selection seem to constitute two relatively independent facets of cognitive control involved in analogical thinking. Selection may act before mapping occurs, while interference influences analogy making only if an interfering object takes part in mapping.     

眼跳的双相调节理论的行为证据

为了研究眼跳的双相调节理论是否适用于人类的视觉系统,本研究测量了人类被试对分别呈现在三种眼跳时间段（基线、眼跳抑制和眼跳增强）内的光栅的朝向辨别准确率。研究发现：相对于光栅呈现在基线时间段内,被试对呈现在抑制（或增强）时间段内的光栅的朝向辨别准确率显著地更低（或更高）（实验1）;另外,只有使用低或中等空间频率光栅作为测试刺激时,才有这种双相调节作用（实验2）。这些结果表明：人类的视觉系统在眼跳过程中存在双相调节机制,并且这种双相调节机制具有刺激选择性。     

基于成本最小化信息的社会性意图识别：来自脑电和行为的证据

与已有研究着重考察如何识别客体导向性意图(动作以物理对象为目标, 而不涉及其他人)不同, 本研究对人们如何识别社会性意图(动作以指向社会主体为目标以影响对方的交互行为)进行了探讨。基于两交互主体在整体层面应遵循效用最大化的分析, 提出当A协助B达成目标状态所需要的成本小于B单独实现该目标状态所需要的成本时(简称为成本最小化信息), 其可被识别为具有社会性意图。通过在B面前设置栅栏的方法操纵成本最小化信息, 以指示不同意图类型的脑电μ抑制程度、对不同变化的敏感性(辨别力)为指标, 对该假设进行了检验。结果显示, 相比客体导向性意图的控制条件(即A将目标物苹果放置在石头前), 当A将目标物苹果放置在被栅栏挡住的B前, 其动作可减少B单独获取该苹果的动作成本, 即符合成本最小化条件时, μ的抑制程度更高(实验1), 且对结构改变(某两个动画中充当相同角色的智能体互换)的辨别力更强, 但对角色交换(某个动画中两个智能体的角色交换)的辨别力更弱(实验3a); 而当栅栏不存在时, 虽然A的运动路径与实验1相同, 但A将苹果放置在B前的成本大于B自身获取苹果的成本, 即不符合成本最小化条件, 条件间μ抑制的差异消失(实验2), 且对不同动作模式中变化的辨别相当(实验3b)。鉴于已有研究表明社会性意图所诱发的μ抑制强于客体导向性意图, 且人们对存在社会性意图的两个智能体间的结构改变更容易辨别, 而对角色交换不敏感, 故上述结果揭示, 两个个体的行为是否满足成本最小化影响人们对动作意图的识别, 支持成本最小化信息是社会性意图识别线索的观点。     

Trait anxiety and impaired control of reflective attention in working memory

The present study investigated whether the control of reflective attention in working memory (WM) is impaired in high trait anxiety individuals. We focused on the consequences of refreshing—a simple reflective process of thinking briefly about a just-activated representation in mind—on the subsequent processing of verbal stimuli. Participants performed a selective refreshing task, in which they initially refreshed or read one word from a three-word set, and then refreshed a non-selected item from the initial phrase or read aloud a new word. High trait anxiety individuals exhibited greater latencies when refreshing a word after experiencing the refreshing of a word from the same list of semantic associates. The same pattern was observed for reading a new word after prior refreshing. These findings suggest that high trait anxiety individuals have difficulty resolving interference from active distractors when directing reflective attention towards contents in WM or processing a visually presented word.     

An examination of the roles of trauma exposure and posttraumatic stress disorder on emotion regulation strategies of Operation Iraqi Freedom,Operation Enduring Freedom,and Operation New Dawn veterans

Theories of posttraumatic stress disorder (PTSD) implicate emotional processes, including difficulties utilizing adaptive emotion regulation strategies, as critical to the etiology and maintenance of PTSD. Operation Iraqi Freedom, Operation Enduring Freedom, and Operation New Dawn (OIF/OEF/OND) veterans report high levels of combat exposure and PTSD. We aimed to extend findings suggesting that emotion regulation difficulties are a function of PTSD, rather than combat trauma exposure or common comorbidities, to OIF/OEF/OND veterans, in order to inform models of PTSD risk and recovery that can be applied to returning veterans. We tested differences in emotion regulation, measured with the Difficulties in Emotion Regulation Scale and Emotion Regulation Questionnaire, among trauma-exposed veterans with (n = 24) or without PTSD (n = 22) and healthy civilian comparison participants (n = 27) using multivariate analyses of covariance, adjusting for major depressive disorder, anxiety disorders, and demographic variables (age, sex, and ethnicity). Veterans with PTSD reported more use of expressive suppression and more difficulties with emotion regulation than veterans without PTSD and healthy comparison participants. Groups did not differ on cognitive reappraisal. Findings suggest the key role of PTSD above and beyond trauma exposure, depression, and anxiety in specific aspects of emotion dysregulation among OIF/OEF/OND veterans. Interventions that help veterans expand and diversify their emotion regulation skills may serve as helpful adjunctive treatments for PTSD among OIF/OEF/OND veterans.     

Thought suppression and its effects on thought frequency, appraisal and mood state in individuals with obsessive-compulsive disorder

Leading models of obsessive-compulsive disorder (OCD) implicate thought suppression as a key factor in the escalation and persistence of the disorder. This experiment examined the effects of suppression on the frequency of obsessional thoughts in 50 individuals with a primary diagnosis of OCD, and also investigated the effects of participants' appraisals regarding their failures in thought control on distress about intrusive thoughts and on mood. Participants' most upsetting obsessional thought was primed and they then monitored its occurrence over two 4-min intervals. In the first interval, half of the participants were instructed to suppress their obsessional thought and half were instructed not to suppress any thoughts. In the second interval, all participants were given the 'Do Not Suppress' instructions. Participants rated their suppression effort and discomfort over thought occurrences after each interval and recorded their appraisals of thought recurrences during the first interval. Mood state was then reassessed. No ironic effect of suppression on frequency was noted. However, negative appraisals of thought recurrences were associated with more discomfort over thought occurrences and more negative mood at Time 2. These findings suggest that interpretations regarding failures in thought control may be of central importance in understanding obsessional problems.     

Dissociation and memory suppression: A comparison of high and low dissociative individuals’ performance on the Think–No Think task

The present study examined whether high and low dissociative individuals differ in their ability to keep target stimuli out of their awareness (suppression) and how this relates to their memory of those targets during a later cued recall task. The prediction was that high dissociators display a general inability to focus attention and that their distractibility undermines successful suppression, thereby enhancing memory for suppressed items. College students with high (n = 35) and low (n = 33) scores on the Dissociative Experiences Scale participated in a Dutch version of Anderson and Green’s (2001) Think–No Think (TNT) task. Overall, a significant suppression effect emerged. However, no differences between high and low dissociators were observed. Thus, the present results do not confirm that dissociation is linked to heightened distractibility.