Attentional bias for body and food in eating disorders: increased distraction, speeded detection, or both?

Previous research suggests that eating disorder patients show an attentional bias for body- and food-related information. However, so far little is known about the mechanisms that underlie the attentional favoring of this particular information in eating disorder patients. In the present study, we used both a body and a food visual search task to study speeded detection and increased distraction in eating disorder patients (n=67) and healthy controls (n=60). Compared with controls, eating disorder patients showed evidence of speeded detection of body-related information, and increased distraction by food information. These results suggest that the mechanism underlying the biased attentional allocation of eating disorder patients varies, and is dependent upon the type of information they are presented with.     

The role of color in human face detection

Significant advances have been made in understanding human face recognition . However, a fundamental aspect of this process, how faces are located in our visual environment, is poorly understood and little studied. Here we examine the role of color in human face detection. We demonstrate that detection performance declines when color information is removed from faces, regardless of whether the surrounding scene context is rendered in color. Furthermore, faces rendered in unnatural colors are hard to detect, suggesting a role beyond simple segmentation. When faces are presented such that half the surface is colored appropriately, and half unnaturally, performance declines. This suggests that observers are not simply using the presence of skin color "patches" to detect faces. Rather, our data suggest that detection operates via a face template combining diagnostic color and face-shape information. These findings are consistent with color-template approaches used in some computer-based face detection systems.     

某院3年医院感染患者细菌分离及耐药性分析

应用WHONET5．3软件对2005年1月至2007年12月检出的1749株病原菌种类、分布及其耐药性进行统计分析。结果发现院内感染病原菌以条件致病菌为主,革兰阴性菌检出率61．8％,革兰阳性菌的检出率33％,真菌检出率为5．2％。大肠埃希菌及肺炎克雷伯菌属的ESBLs阳性率分别为34．4％和48．9％,MRSA和MRCNS的检出率分别为40．8％和36．4％。大多数病原菌对抗生素产生多重耐药性。由此可见,由于临床抗生素的广泛使用,病原菌不断变迁且其耐药性逐渐上升,应加强耐药性监测及合理使用抗生素,以有效控制细菌感染和耐药性播散。     

Image Manipulation as Research Misconduct

A growing number of research misconduct cases handled by the Office of Research Integrity involve image manipulations. Manipulations may include simple image enhancements, misrepresenting an image as something different from what it is, and altering specific features of an image. Through a study of specific cases, the misconduct findings associated with image manipulation, detection methods and those likely to identify such manipulations, are discussed. This article explores sanctions imposed against guilty researchers and the factors that resulted in no misconduct finding although relevant images clearly were flawed. Although new detection tools are available for universities and journals to detect questionable images, this article explores why these tools have not been embraced.

线索靶子关联和搜索策略对注意捕获的作用

采用线索化范式, 通过实验任务设计线索与靶子不同的关联并鼓励被试采用不同的搜索策略, 探讨线索与靶子间的知觉关联、语义关联及特征独子检测模式、特征搜索模式对注意捕获的作用。通过线索无效条件和线索有效条件反应时之差判断每一条件下的捕获量, 并综合各条件的反应情况做出结论如下：(1)线索与靶子的知觉关联调控注意捕获, 其效应不受语义关联和搜索策略影响; (2)线索与靶子的语义关联只在排除知觉关联后调控注意捕获; (3)控制知觉关联和语义关联后, 特征搜索模式不影响注意捕获, 而特征独子检测模式对注意捕获有影响。这表明语义知识和知觉经验根据当前任务要求共同作用指导个体的视觉加工, 表现了人类加工系统的灵活性和可调节性。     

Should metacognition be measured by logistic regression?

Are logistic regression slopes suitable to quantify metacognitive sensitivity, i.e. the efficiency with which subjective reports differentiate between correct and incorrect task responses? We analytically show that logistic regression slopes are independent from rating criteria in one specific model of metacognition, which assumes (i) that rating decisions are based on sensory evidence generated independently of the sensory evidence used for primary task responses and (ii) that the distributions of evidence are logistic. Given a hierarchical model of metacognition, logistic regression slopes depend on rating criteria. According to all considered models, regression slopes depend on the primary task criterion. A reanalysis of previous data revealed that massive numbers of trials are required to distinguish between hierarchical and independent models with tolerable accuracy. It is argued that researchers who wish to use logistic regression as measure of metacognitive sensitivity need to control the primary task criterion and rating criteria.     

Bridging novelty and familiarity-based recognition memory: A matter of timing

Novelty detection is essential to adapt to changes. However, the relationship between novelty detection and visual recognition memory remains unclear. To characterize the temporal dynamics of novelty and its connection to familiarity, we probed early behavioural performance of novelty and familiarity in 31 participants using a speeded go/no-go recognition task with a 600-ms response deadline. Responses to familiarity and novelty produced symmetrical biases and correlated accuracies and biases, but novelty decisions were less accurate and had slower minimal reaction times (410?ms). These processes thus appear to be independent, as suggested by a more efficient system in the case of familiarity, but with common factors bringing overlapping contributions to both processes. This may possibly be explained by the more fluent processing of repeated stimuli, but with familiarity and novelty potentially relying on one decision criterion, as suggested by the correlated and remarkably symmetrical biases. This study supports models that conceptualize novelty and familiarity decisions as two partly overlapping processes.     

Studying Stereotype Accuracy from an Integrative Social‐Personality Perspective

This article proposes an integrative framework for understanding the accuracy and inaccuracy of stereotypes. Specifically, we highlight research issues and traditions from social and personality psychology that do not often intersect, but which can be mutually informative. Within this framework, the social psychologist's interest in the accuracy of group stereotypes is conceptually much like a personality psychologist's interest in the accuracy with which perceivers can identify types of individuals, for example extraverts. Both fields make use, implicitly or explicitly, of personal attributes and behaviors (cues) in assessing accuracy of beliefs about group or individual traits. By using Brunswik's lens model perspective in combination with concepts from signal detection theory, judgments of stereotypes can be discovered to be accurate or inaccurate depending on how perceivers judge or use the cues. In drawing on research traditions and theoretical frameworks from both social and personality psychology, researchers can go beyond an all‐or‐nothing stance regarding stereotype accuracy to achieve a more nuanced understanding of when, how, and to what extent stereotypes are accurate.     

方位维度视觉搜索的影响因素

Duncan等人认为,当目标和干扰子之间差异越大且干扰子彼此之间差异越小时,则目标搜索越快。他们的结论定性地描述了目标搜索斜率（反应时间对呈现项目数的函数）的决定因素。笔者从方位维度刺激关系方面进一步定量探究该问题,并提出决定因素为g(T, D, n)（目标方位和干扰子方位间的函数关系）。实验结果证实目标搜索斜率是由g(T,D,n)值决定,目标搜索斜率随g(T, D, n)值增大而减小,相同g(T, D, n)值条件的目标搜索斜率无显著差异     

基于时空变化的步态识别算法研究

本文提出了一种八椭圆人体模型,并在此基础上提出了基于变化信息的步态识别算法。对每个视频序列,采用基于贝叶斯规则的检测算法检测出目标人体区域;将目标人体区域按比例划分为八个区域并分别用椭圆拟合,建立人体椭圆模型;用人体姿势的时空变化——相邻帧间的模型参数的差值作为特征,用归一化后的Mahalanobis距离和Euclidean距离分别进行相似性度量,NN和KNN技术用于最终的分类。实验结果表明,该算法拥有较高的识别率和较低的计算代价。