影响驾驶安全的驾驶员危险知觉研究述评

危险知觉是指驾驶员对交通情境中的潜在危险进行识别并做出反应的一种能力。目前,驾驶员危险知觉测量主要使用反应时、眼动或主观评定三种测量方法。在测量中,这三种方法各有优缺点,并出现相互结合的研究趋势。为了提高我国交通安全性,结合国外在提高驾驶员危险预期能力和改善视觉搜索模式两个方面的应用研究,未来国内研究可以在探索危险知觉的认知加工特点、影响因素及加快测量技术的商品化应用等方面加以深入。     

The role of pattern recognition in children's exact enumeration of small numbers

Enumeration can be accomplished by subitizing, counting, estimation, and combinations of these processes. We investigated whether the dissociation between subitizing and counting can be observed in 4‐ to 6‐year‐olds and studied whether the maximum number of elements that can be subitized changes with age. To detect a dissociation between subitizing and counting, it is tested whether task manipulations have different effects in the subitizing than in the counting range. Task manipulations concerned duration of presentation of elements (limited, unlimited) and configuration of elements (random, line, dice). In Study 1, forty‐nine 4‐ and 5‐year‐olds were tested with a computerized enumeration task. Study 2 concerned data from 4‐, 5‐, and 6‐year‐olds, collected with Math Garden, a computer‐adaptive application to practice math. Both task manipulations affected performance in the counting, but not the subitizing range, supporting the conclusion that children use two distinct enumeration processes in the two ranges. In all age groups, the maximum number of elements that could be subitized was three. The strong effect of configuration of elements suggests that subitizing might be based on a general ability of pattern recognition.     

Upper limb movement analysis during gait in multiple sclerosis patients

PurposeGait disorders in multiple sclerosis (MS) are well studied; however, no previous study has described upper limb movements during gait. However, upper limb movements have an important role during locomotion and can be altered in MS patients due to direct MS lesions or mechanisms of compensation. The aim of this study was to describe the arm movements during gait in a population of MS patients with low disability compared with a healthy control group.MethodsIn this observational study we analyzed the arm movements during gait in 52 outpatients (mean age: 39.7 ± 9.6 years, female: 40%) with relapsing-remitting MS with low disability (mean EDSS: 2 ± 1) and 25 healthy age-matched controls using a 3-dimension gait analysis.ResultsMS patients walked slower, with increased mean elbow flexion and decreased amplitude of elbow flexion (ROM) compared to the control group, whereas shoulder and hand movements were similar to controls. These differences were not explained by age or disability.ConclusionUpper limb alterations in movement during gait in MS patients with low disability can be characterized by an increase in mean elbow flexion and a decrease in amplitude (ROM) for elbow flexion/extension. This upper limb movement pattern should be considered as a new component of gait disorders in MS and may reflect subtle motor deficits or the use of compensatory mechanisms.     

Multivariate pattern analysis of event-related potentials predicts the subjective relevance of everyday objects

Potentially decision-relevant stimuli have been proposed to undergo immediate semantic processing. The current study investigated whether information regarding the general desirability (‘Wanting’) of visually presented ‘everyday’ objects was rapidly and automatically processed. Participants completed a foreground task while their electroencephalogram (EEG) was recorded, and task-irrelevant images were presented in the background. Following this, participants rated the images with regards to Wanting and the potentially related attributes of Relevance, Familiarity, Aesthetic Pleasantness and Time Reference. Multivariate pattern classification was used to predict the ratings from patterns of EEG data. Prediction of Wanting and Relevance was possible between 100 and 150 ms following stimulus presentation. The other dimensions could not be predicted. Wanting and Relevance ratings were highly correlated and displayed similar feature weight maps. The current results suggest that the general desirability and subjective relevance of everyday objects is rapidly and automatically processed for a wide range of visual stimuli.     

The role of visible persistence for perception of visual bilateral symmetry1

Abstract: Although the detection of visual bilateral symmetry has been claimed to be highly efficient, the possible involvement and function of visual memory in such efficient mechanisms has rarely been examined. We hypothesized that symmetry perception is rapid, as it can be achieved from rapidly decaying information of visible persistence. To test this hypothesis, we employed a temporal integration paradigm. A symmetric dot pattern was randomly divided into two asymmetric patterns and presented successively with a blank screen presented between patterns. Observers could detect symmetry when the two patterns were presented close in time (Experiment 1), indicating that observers perceived symmetry presumably utilizing visible persistence. In addition, the inverse‐intensity effect of visible persistence (Di Lollo & Bischof, 1995) was evident in our temporal integration task of symmetry (Experiment 2). The results of the current study clearly demonstrate that the detection of symmetry can be achieved based on the visible persistence. The large capacity and high spatial precision of visible persistence might be adequate for the rapid and spatially global encoding of visual symmetry.     

浅析专家会诊中心在门诊医疗中的作用

随着物质生活水平的日益提高,人们对医疗、保健的需求越来越高。为缓解看专家门诊难和在门诊能及时解决疑难杂症会诊问题,江苏省人民医院于1997年成立了高级专家会诊中心。中心成立十余年来,会诊、就诊的患者逐年增多,中心以优质的服务,得到患者的好评,作为门诊医疗的“特殊”窗口发挥了越来越大的作用。     

Expertise in the Game of Go and Levels of Visuospatial and Pattern Recognition Abilities

The results of existing research indicate higher levels of visuospatial and pattern recognition abilities in experts in the game of Go compared to novices. However, the tasks included in the research have been focused only on Go‐game situations. This study aimed to verify the hypothesis that experts in the game of Go would achieve higher scores, compared to novices, on behavioral tests measuring visuospatial abilities and that pattern recognition tests would be a predictor of group membership (experts, low‐skill players, novices). We consider that the game of Go can be treated as a special case of tasks related to visuospatial abilities and pattern recognition. Sixty men participated in the study, including 17 experts in the game of Go, 13 low‐skill players, and 30 novices. The results of behavioral tests—the advanced version of Raven's Progressive Matrices and the APIS‐Z Test's Visuospatial Abilities subscale, which measure pattern recognition and visuospatial abilities, respectively—confirmed the hypotheses.     

A Common Force-Sharing Pattern in Joint Action That Consists of Four People

The authors examined the force-sharing patterns in a joint action performed by a group of two, three, or four people compared with a solo action. In the joint actions, 28 participants produced periodic isometric forces such that the sum of forces they produced cycled between 5% and 10% maximum voluntary contraction with the right hand at 1 Hz. In both the three- and four-person tasks, the correlation between forces produced by two of the three or four participants was negative, and the remaining one or two participants produced intermediate forces. The errors of force and interval and force variabilities were smaller in four- and three-people groups than individuals. Four- and three-people groups thus performed better than individuals.     

Analysis of structural equation model with ignorable missing continuous and polytomous data

The main purpose of this article is to develop a Bayesian approach for structural equation models with ignorable missing continuous and polytomous data. Joint Bayesian estimates of thresholds, structural parameters and latent factor scores are obtained simultaneously. The idea of data augmentation is used to solve the computational difficulties involved. In the posterior analysis, in addition to the real missing data, latent variables and latent continuous measurements underlying the polytomous data are treated as hypothetical missing data. An algorithm that embeds the Metropolis-Hastings algorithm within the Gibbs sampler is implemented to produce the Bayesian estimates. A goodness-of-fit statistic for testing the posited model is presented. It is shown that the proposed approach is not sensitive to prior distributions and can handle situations with a large number of missing patterns whose underlying sample sizes may be small. Computational efficiency of the proposed procedure is illustrated by simulation studies and a real example.The work described in this paper was fully supported by a grant from the Research Grants Council of the HKSAR (Project No. CUHK 4088/99H). The authors are greatly indebted to the Editor and anonymous reviewers for valuable comments in improving the paper; and also to D. E. Morisky and J.A. Stein for the use of their AIDS data set.