Executive function outcomes of children with traumatic brain injury sustained before three years

Traumatic brain injury (TBI) is a common cause of disability in childhood. While the outcomes of TBI sustained in school years has been heavily researched, very little is known about the impact of TBI in infants and young children. The aim of this study was to investigate the impact of TBI on executive function (EF) in children who sustained a TBI before 3 years of age. A group of 55 children, 19 with a mild TBI, 16 children with a moderate-severe TBI, and 20 uninjured comparison children participated. The EF of children aged 3 to 6 years were compared using child-based measures of attentional control and information processing. Parents completed questionnaires rating their child's EF. Severity groups differed on the child-based EF measure of attentional control with children with TBI performing below the control group. There were no significant group differences for information processing or parent-rated EF. It appears that children who sustain a TBI before the age of 3 years display impairments in some areas of attentional control 3–4 years postinjury. The findings fit with the existing EF literature for older children.     

General analytical solution for stress intensity factor of a hypocycloid hole with many cusps in an infinite plate

In this article, the problem for the determination of the displacement functions and the stress intensity factors (SIFs) around a boundary of a hypocycloid hole with cusps in an infinite elastic plate subject to normal and shear stresses are presented. A hole with cusps (hypocycloid) is mapped onto a unit circle and the modified complex potential is used for solving the relevant boundary value problems. An analytical solution for the SIF of a hypocycloid hole is obtained. For a special case, our results agree with others.     

心理负荷的评估:基于神经人因学的视角

心理负荷的评估正经历着从传统工效学向神经人因学的变革.EEG、ERPs、fMRI、fNIRS和TCD等神经科学研究技术为这场变革提供了有力的工具.研究发现:在单任务情境下,随着操作者心理负荷的增加,脑电α波活动减弱,θ波活动增强,并且前额皮层血流、左侧额下回血液氧合血红蛋白浓度变化均增加,大脑动脉血流速度也增快;在双任务情境下,随着操作者主任务心理负荷的增加,次任务的N1、新异P3和P3b等ERPs成分波幅降低.依据这些研究成果,学者们利用人工神经网络、支持向量机等模式分类算法实现了对心理负荷的实时在线评估.但是,各种研究技术在敏感性、诊断力、主任务干扰、实施需求、可接受性和信度等方面各有优势与不足.在未来研究中,要注意促进相关技术的融合、提高其可接受性,并充分利用模式识别算法提高其诊断力和敏感性.     

A Controlled Pilot-Outcome Study of Sensory Integration (SI) in the Treatment of Complex Adaptation to Traumatic Stress

This study tested whether sensory integration (SI) treatment combined with psychotherapy would improve symptom outcome over psychotherapy alone in the treatment of complex posttraumatic stress, as measured by the Disorders of Extreme Stress Not Otherwise Specified (DESNOS) clinical construct in a group of 10 adult patients with histories of childhood abuse. DESNOS symptoms were assessed at three time periods (T1, baseline; T2, after experimental group SI treatment; and T3, after wait-list control group SI treatment) using the Structured Interview for Disorders of Extreme Stress (SIDES). The Sensory Learning Program? (SLP), developed by the Sensory Learning Institute of Boulder, Colorado, was used as the SI treatment modality. Results indicated significant differential improvement for the group treated with SLP in SIDES Total Score (T1/T2 and T2/T3), Self Perception (T1/T2 and T2/T3), Affect Regulation (T2/T3), and Alterations in Meaning (T1/T2).     

Us versus them: Understanding the process of race perception with event-related brain potentials

Race is powerful social signal, imbued with a great deal of meaning and capable of affecting a wide range of behaviours and judgements. This review focuses on the use of event-related brain potentials (ERPs) to better understand the process and implications of race perception. Research to date repeatedly demonstrates the speed and automaticity with which racial category membership is encoded. The quick and relatively obligatory encoding of racial ingroup and outgroup distinctions in turn affects a variety of subsequent racially biased behaviours. Such findings not only speak to the close link between social categorization and behaviour, but also have been used to understand how the effects of race perception can be moderated.     

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.     

Error adaptation in mental arithmetic

Until now, error and conflict adaptation have been studied extensively using simple laboratory tasks. A common finding is that responses slow down after errors. According to the conflict monitoring theory, performance should also improve after an error. However, this is usually not observed. In this study, we investigated whether the characteristics of the experimental paradigms normally used could explain this absence. More precisely, these paradigms have in common that behavioural adaptation has little room to be expressed. We therefore studied error and conflict adaptation effects in a task that encounters the richness of everyday life's behavioural adaptation—namely, mental arithmetic, where multiple solution strategies are available. In accordance with our hypothesis, we observed that posterror accuracy increases after errors in mental arithmetic. No support for conflict adaptation in mental arithmetic was found. Implications for current theories of conflict and error monitoring are discussed.     

The influence of dimensional overlap on location-related priming in the Simon task

Choice reaction times are shorter when stimulus and response locations are compatible than when they are incompatible as in the Simon effect. Recent studies revealed that Simon effects are strongly attenuated when there is temporal overlap with a different high-priority task, accompanied by a decrease of early location-related response priming as reflected in the lateralized readiness potential (LRP). The latter result was obtained in a study excluding overlap of stimulus location with any other dimension in the tasks. Independent evidence suggests that location-related priming might be present in conditions with dimensional overlap. Here we tested this prediction in a dual-task experiment supplemented with recording LRPs. The secondary task was either a standard Simon task where irrelevant stimulus location overlapped with dimensions of the primary task or a Stroop-like Simon task including additional overlap of irrelevant and relevant stimulus attributes. At high temporal overlap, there was no Simon effect nor was there stimulus-related response priming in either condition. Therefore stimulus-triggered response priming seems to be abolished in conditions of limited capacity even if the likelihood of an S–R compatibility effect is maximized.     

Attention and action: The role of response mappings in auditory attention switching

Switching auditory attention incurs a performance decrement (i.e. auditory attention-switch costs). Using an auditory attention-switching paradigm, we aimed to generalise these across different response mappings. In all three experiments, two number words, spoken by a female and male speaker, were presented dichotically via headphones. A visual cue indicated the gender of the to-be-attended speaker in each trial. The task was a magnitude judgement of the relevant number word (i.e. smaller vs. larger than 5). We additionally varied the interval between cue onset and auditory stimulus onset (cue-stimulus interval) to explore cue-based preparatory effects. In Experiment 1, attention switching was more costly with direct-verbal responses (e.g. ‘smaller’) than in the shadowing task (e.g. ‘three’). In Experiment 2, performance was largely similar for direct-verbal responses and abstract-verbal responses (e.g. ‘left’). In Experiment 3, performance was generally worse with abstract-verbal responses than with abstract-manual responses (e.g. left key press) and auditory attention-switch costs were similar for both response mappings. Overall, auditory switch costs occurred more or less invariably across response mappings in categorical (magnitude) judgements suggesting a minor role of the response mapping in auditory attention switching. Furthermore, verbal identity-based judgements (i.e. shadowing) generally seem to benefit from ideomotor compatibility.