Response preparation with anticues in children and adults

We examined the ability of children (mean age: 10.4 years) and adults (mean age: 20.7 years) to prepare finger keypress responses in an anticue paradigm by presenting left and right spatial cues, which specified right and left hand finger responses, respectively. Four time intervals separated cue onset from target onset: 200 ms, 600 ms, 1000 ms, and 2000 ms. Results showed that, overall, children responded slower and less accurately than did adults; nevertheless they were equally effective in using anticue information to reduce reaction time with preparation intervals of 600 ms and longer. This outcome is discussed in terms of a slow, voluntary, top-down executive process that redirects motor preparation from the ipsi- to the contralateral hand. The absence of an age effect suggests an early maturation of the underlying neural mechanisms.     

应用Uni Web Viewer探讨经关键孔脑室穿刺的方法

应用Uni Web Viewer软件,通过基线平行于Frankfurt平面的颅脑CT30例,探讨经关键孔脑室穿刺的方法。模拟从关键孔下脑皮质,与前后分别呈55°、50°、45°行侧脑室穿刺。结果以x±s表示,统计采用多个样本方差齐性检验,单因素多样本均数F检验,P〈0．05为显著统计学差异。与前后呈50°,头尾呈20°,深度5cm,为经关键孔脑室穿刺的优选方案。     

双向偏见引发冲突情境下自我归类对民族社会化觉察的影响——来自景颇族、傣族和汉族初中生的证据

采用情境实验法和故事补全任务,考察双向偏见引发冲突情境下的自我归类对景颇族、傣族与汉族初中生的民族社会化觉察的影响。结果表明,作为冲突事件的当事者,景颇族学生和傣族学生觉察到的促进和睦、文化社会化及促使不信任等民族社会化信息存在差异;景颇族、傣族和汉族学生的自我归类存在差异;自我归类对促进和睦、文化社会化与报告权威等信息的觉察的影响亦存在民族差异。在双向偏见冲突情境下,三族学生的自我归类与民族社会化觉察有一定关系:无论是做当事者/内群体归类、旁观者/外群体归类,还是做调解者/群际归类,被试对促进和睦的觉察均最多。偏见准备主要与当事者归类有关,而进行调解者归类的被试更容易觉察到"报告权威"。     

Modality-specific preparatory influences on the flexibility of cognitive control in task switching

In the current study, we addressed modality-specificity of the flexibility of cognitive control. We compared performance in single-task and mixed-tasks blocks between blocked auditory and visual stimuli assessing alternation costs (single vs. mixed). Mixed blocks comprised task switches only. The tasks consisted of numerical parity, magnitude, and distance judgments about numbers between one and nine without five. A cue indicated the relevant task. The cue–stimulus interval was varied (short vs. long interval) to examine preparation effects. The results indicated higher response times (RTs) and error rates (ERs) in mixed- vs. single-tasks blocks. The alternation costs in ERs were larger for auditory compared to visual stimulus presentation. Moreover, the reduction of RT alternation costs based on increased preparation time was more pronounced for the auditory modality compared to the visual modality. These results suggest a modality-specific influence on processes involved in maintaining and updating task sets in working memory.     

从JNC高血压指南的演变史看盐与高血压的关系

高血压是当今世界上最大的流行病,是脑卒中、心脏病及肾脏病最主要的危险因素。通过回顾比较不同时期的JNC高血压指南,了解对盐与高血压关系认识的发展过程,体会限盐对高血压防治的重要性及发展前景。     

Decreased load on general motor preparation and visual-working memory while preparing familiar as compared to unfamiliar movement sequences

Learning movement sequences is thought to develop from an initial controlled attentive phase to a more automatic inattentive phase. Furthermore, execution of sequences becomes faster with practice, which may result from changes at a general motor processing level rather than at an effector specific motor processing level. In the current study, we examined whether these changes are already present during preparation. Fixed series of six keypresses, either familiar or unfamiliar, had to be prepared and executed/withheld after a go/nogo signal. Reaction time results confirmed that familiar sequences were executed faster than unfamiliar sequences. Results derived from the electroencephalogram showed a decreased demand on general motor preparation and visual-working memory before familiar sequences as compared to unfamiliar sequences. We propose that with familiar sequences the presetting segments of responses is less demanding than with unfamiliar sequences, as familiar sequences can be regarded as less complex than unfamiliar sequences. Finally, the decreasing demand on visual-working memory before familiar sequences suggests that sequence learning indeed develops from an attentive to an automatic phase.     

Trauma awareness and preparedness: Their influence on posttraumatic stress disorder development related to armed conflict experience

This study examined influences of trauma awareness and preparedness on the development of posttraumatic stress disorder (PTSD) in civilian and military personnel with exposure to the civil war. Participants were 302 people with exposure to civil war in the Democratic Republic of Congo (civilians = 68%; females = 47%; age range = 16 to 76 years old, SD = 13.58 years). Participants completed the Posttraumatic Checklist Scale, General Self-Efficacy Scale, and Traumatic Events List. The data were analysed to predict PTSD development from trauma awareness and preparedness, taking exposure to multiple traumas into account as a risk factor. Findings suggest that trauma awareness and preparedness play an important role among military personnel in moderating the risk of developing PTSD, more so than among the civilian population. Mental health professionals working with civil war survivors should seek to explore trauma awareness and preparedness as resources for minimising risk for PTSD in armed conflict situations.     

Private blog reflections connecting course content with field experiences: preservice teachers grapple with teacher identity

A challenge experienced within teacher preparation programs is the ability to help preservice teachers connect educational theory with teaching practice. Guided by Dewey's phases of reflective thinking and Schön’s reflection on action as an ethic for inquiry, we embedded a systematic reflection of written responses, recorded in a private weblog over the course of a 15-week intermediate reading methods course. Inductive thematic analysis of responses revealed the following themes: visceral thought, vulnerability, interpretation of course content, and identity formation toward becoming a classroom teacher. Our findings exemplify how systematic reflection in a private digital space contributed to the development of preservice teachers’ professional identities.     

Queuing or sharing? A critical evaluation of the single-bottleneck notion

The model of a single central bottleneck for human information processing is critically examined. Most evidence cited in support of the model has been observed within the overlapping tasks paradigm. It is shown here that most findings obtained within that paradigm and that were used to support the model are also consistent with a simple resource model. The most prominent findings are the millisecond-for-millisecond slope at the left of the RT2-SOA curve, the high RT1-RT2 correlation, the additivity of the effects on RT2 of SOA and of the difficulty of selecting R2, and the washout of the effect of S2 discriminability on RT2 in a dual-task condition. In addition, the asymmetry of the effects of the dual-task requirement on RT1 and RT2 can be accounted for by the resource model provided that it assumes uneven allocation of resources, which is quite reasonable in view of the task asymmetry inherent in the demand characteristics of the paradigm. The same is true for two other findings that appear to support the single-bottleneck model-that in the dual-task condition, the demand of the first task affects equally RT1 and RT2 and that its effect on RT1 is the same as the corresponding effect in the single-task condition. Furthermore, the single-bottleneck model is hard to reconcile with a negative slope at the left of the RT1-SOA curve or a positive slope at the left of the IRI-SOA curve, unless augmented by ancillary assumptions that are yet to be substantiated. Representative data were fit by each of the models using its optimal set of parameters. Both models achieved quite good degrees of fit. It is further argued that since the overlapping tasks paradigm is heavily biased in favor of a speedy reaction to the stimulus that appears first, it is nonoptimal for testing the central bottleneck model. Finally, the bottleneck model is examined in terms of other scientific criteria.     

Representative co-design: Utilising a source of experiential knowledge for athlete development and performance preparation

Contemporary models for athlete development and performance preparation in sport have advocated a role re-conceptualisation for coaches grounded as learning environment designers. Within this re-conceptualisation, expert practitioners are encouraged to draw upon their experiential knowledge to design representative and meaningful learning activities that place the performer-environment interaction at its core. However, we propose that, currently, a critical source of experiential knowledge is often overlooked within the process of learning design – that of performers. Specifically, practitioner-performer interactions could enrich the design of learning environments by promoting the utilisation of soliciting affordances and encouraging the psychological engagement of performers. This paper introduces the concept of representative co-design – a notion which builds on existing research by framing how the insights and experiences of performers can be negotiated within the design of practice tasks that seek to faithfully simulate interacting constraints of competition to enrich learning environments. We frame the notion of representative co-design, and contend its importance within more contemporary athlete development and performance preparation models, at two levels: (i) that of enriching physical education curricula to develop thought provoking, ‘intelligent’ child/adolescent learners, and (ii) that of enriching contemporary athlete preparation models in high-performance sport to enhance learning and engagement, and to develop ‘next generation’ coaches within current athletes. To bring this conceptualisation to life, we present two exemplars demonstrating the notion of representative co-design, while concurrently highlighting areas for future research.