认知诊断CAT中项目曝光控制方法的比较

项目曝光率关系到题库建设和测验安全,是计算机化自适应测验(Computerized Adaptive Testing, CAT)需要考虑的重要问题。在认知诊断 CAT 情形下,首先基于传统 CAT 中 a-分层方法的思想提出按项目信息量对题库分层的分层多阶段(Stratified Multistage, SM)选题方法;然后将 SM 方法与项目合格(Item Eligibility, IE)方法相结合得到SMIE方法。在此基础上,开展模拟研究比较SM、IE、SMIE、最大修正优先指标(Maximum Modified Priority Index, MMPI)方法、限制阈值(Restrictive Threshold, RT)方法和限制进度(Restrictive Progressive, RPG)方法的选题表现。总体上,它们的测量精度从高到低依次为IE、SM、SMIE、RT、RPG和MMPI方法;项目曝光分布均匀性的优劣次序为MMPI、RPG、SMIE、RT、SM和IE方法;SMIE和RT方法能较好地平衡测量精度和项目曝光均匀性要求。     

Visuospatial working memory,auditory discrimination,and attention

ABSTRACT

The present study examined the degree to which tests of visuospatial storage capacity tap into domain-general storage and attention processes. This was done by comparing performance of visuospatial memory tasks with performance on sound-based sensory discrimination tasks. We found that memory task- and discrimination task performance both tapped into a cross-modality factor (visual and auditory). We further examined the degree to which this common variance could be explained by attention control and sustained attention. These attention factors accounted for roughly 60% of the variance in memory. This indicates that tests of visuospatial memory capacity reflect more than modality-specific memory.     

Repressors report fewer intrusions following a laboratory stressor: The role of reduced stressor-relevant concept activation and inhibitory functioning

Abstract

This study investigated whether a repressive coping style is associated with fewer intrusions following an experimentally controlled stressor. Furthermore, we examined whether lower activation of stressor-relevant concepts in long-term memory and better inhibitory functioning may contribute to this association. Extreme-scoring participants on a trait anxiety and a social desirability scale were selected to form repressor (n=35), low anxious (n=15), high anxious (n=30), and defensive (n=21) groups. In line with predictions, repressors reported fewer intrusions following a failure manipulation compared to non-repressors. Furthermore, pre-stressor inhibitory functioning was negatively associated with color-naming interference of stressor-related words. This suggests that overall, higher inhibitory control is related to lower activation of failure-related concepts. However, there was no evidence that concept activation and inhibitory control were responsible for repressors’ lower number of self-reported intrusions.     

Differences in Sexual Behaviors and Teen Dating Violence among Black,Hispanic, and White Female Adolescents

We examined differences in sexual behaviors among White, Black, and Hispanic adolescent females exposed to dating or sexual violence (DSV) using the 2009 Youth Risk Behavior Survey. We also examined the interaction effect of exposure to DSV and race or ethnicity on sexual behaviors. Sexual behaviors were significantly associated with both race or ethnicity and DSV; DSV was a stronger predictor of sexual behaviors than race or ethnicity; and the effect of DSV on condom use was more pronounced among Hispanic adolescents, whereas the effect of DSV on birth control use was more pronounced among both Black and Hispanic adolescents. Adolescent health programs should simultaneously address DSV and sexual risk reduction, with particular emphasis on birth control and condom use among ethnic minority populations.     

Executive functions in decision making: An individual differences approach

This individual differences study examined the relationships between three executive functions (updating, shifting, and inhibition), measured as latent variables, and performance on two cognitively demanding subtests of the Adult Decision Making Competence battery: Applying Decision Rules and Consistency in Risk Perception. Structural equation modelling showed that executive functions contribute differentially to performance in these two tasks, with Applying Decision Rules being mainly related to inhibition and Consistency in Risk Perception mainly associated to shifting. The results suggest that the successful application of decision rules requires the capacity to selectively focus attention and inhibit irrelevant (or no more relevant) stimuli. They also suggest that consistency in risk perception depends on the ability to shift between judgement contexts.     

外伤性脑梗死的病因分析与防治策略

外伤性脑梗死是颅脑外伤患者比较常见且严重的一种并发症.其病因主要是脑血管壁损伤、血管受机械牵拉挤压、脑血管痉挛及低灌注、氧自由基及其他血管活性物质的改变.随着影像技术的发展进步,外伤性脑梗死的早期诊断已基本能做到,了解其主要发病机制以后,针对性地给予扩容,保证脑灌注压.通过提早预防、早期手术和内科药物、物理治疗方法,改善预后.     

医疗服务成本控制过程伦理范式的选择

不同伦理范式对医疗服务成本控制过程会产生不同的影响.运用经济伦理学及管理伦理学的原理和方法,结合医疗卫生服务机构的行业性质及特点,选择出现实可行的医疗服务成本控制过程的伦理范式.使医疗卫生服务机构在医疗服务成本控制过程中,从成本控制标准的确定、成本控制方法及途径的选择到成本控制结果的分析及考评等环节融入相关伦理内涵.使医疗服务成本控制更好地遵循恰当的伦理范式,更好地履行医疗卫生服务机构的宗旨和职责.     

Unconscious task set priming with phonological and semantic tasks

Whether unconscious stimuli can modulate the preparation of a cognitive task is still controversial. Using a backward masking paradigm, we investigated whether the modulation could be observed even if the prime was made unconscious in 100% of the trials. In two behavioral experiments, subjects were instructed to initiate a phonological or semantic task on an upcoming word, following an explicit instruction and an unconscious prime. When the SOA between prime and instruction was sufficiently long (84 ms), primes congruent with the task set instruction led to speedier responses than incongruent primes. In the other condition (36 ms), no task set priming was observed. Repetition priming had the opposite tendency, suggesting the observed task set facilitation cannot be ascribed solely to perceptual repetition priming. Our results therefore confirm that unconscious information can modulate cognitive control for currently active task sets, providing sufficient time is available before the conscious decision.     

Alcohol increases hypnotic susceptibility

One approach to hypnosis suggests that for hypnotic experience to occur frontal lobe activity must be attenuated. For example, cold control theory posits that a lack of awareness of intentions is responsible for the experience of involuntariness and/or the subjective reality of hypnotic suggestions. The mid-dorso-lateral prefrontal cortex and the ACC are candidate regions for such awareness. Alcohol impairs frontal lobe executive function. This study examined whether alcohol affects hypnotisability. We administered 0.8 mg/kg of alcohol or a placebo to 32 medium susceptible participants. They were subsequently hypnotised and given hypnotic suggestions. All participants believed they had received some alcohol. Participants in the alcohol condition were more susceptible to hypnotic suggestions than participants in the placebo condition. Impaired frontal lobe activity facilitates hypnotic responding, which supports theories postulating that attenuation of executive function facilitates hypnotic response, and contradicts theories postulating that hypnotic response involves enhanced inhibitory, attentional or other executive function.     

Effects of Backpack Carriage on Dual-Task Performance in Children During Standing and Walking

Primary school children perform parts of their everyday activities while carrying school supplies and being involved in attention-demanding situations. Twenty-eight children (8–10 years old) performed a 1-legged stance and a 10 m walking test under single- and dual-task situations in unloaded (i.e., no backpack) and loaded conditions (i.e., backpack with 20% of body mass). Results showed that load carriage did not significantly influence children's standing and walking performance (all p > .05), while divided attention affected all proxies of walking (all p < .001). Last, no significant load by attention interactions was detected. The single application of attentional but not load demand negatively affects children's walking performance. A combined application of both did not further deteriorate their gait behavior.