大学生镜像书写及其机制探讨

本研究选择60名右利大学生(男女各半)为被试,在笔划水平上对十四种不同书写方式下快速书写时所出现的自发性镜像书写进行了研究。所有被试随机分为人数相等的实验、对照两组,组内男女各半。对实验组加以注意干扰。书写内容是十个阿拉伯数字(0—9)及十三个汉字组成的一句话。本研究结果表明:注意干扰、感觉的反馈调节,书写内容的特点是影响镜像书写出现的重要因素。作者在分析国内外有关镜像书写工作的基础上,进一步提出了“稳态系统”理论。     

Stereo-motion cooperation and the use ofmotion disparity in the visual perception of 3-D structure

When an observer views a moving scene binocularly, both motion parallax and binocular disparity provide depth information. In Experiments lA-1C, we measured sensitivity to surface curvature when these depth cues were available either individually or simultaneously. When the depth cues yielded comparable sensitivity to surface curvature, we found that curvature detection was easier with the cues present simultaneously, rather than individually. For 2 of the 6 subjects, this effect was stronger when the component of frontal translation of the surface was vertical, rather than horizontal. No such anisotropy was found for the 4 other subjects. If a moving object is observed binocularly, the patterns of optic flow are different on the left and right retinae. We have suggested elsewhere (Cornilleau-Pérès & Droulez, in press) that this motion disparity might be used as avisual cue for the perception of a 3-D structure. Our model consisted in deriving binocular disparity from the left and right distributions of vertical velocities, rather than from luminous intensities, as has been done in classical studies on stereoscopic vision. The model led to some predictions concerning the detection of surface curvature from motion disparity in the presence or absence of intensity-based disparity (classically termedbinocular disparity). In a second set of experiments, we attempted to test these predictions, and we failed to validate our theoretical scheme from a physiological point of view.     

Illusory conjunctions and the cerebral hemispheres

Two visual half-field experiments tested Moscovitch’s (1979) proposition that cerebral asymmetry does not concern the earliest perceptual stages but only later processing. Subjects were briefly shown displays that included one (Experiment 1) or two (Experiment 2) types of forms differing in size and which, according to previous evidence, might lead to opposite laterality effects. Laterality effects were assessed for correct detections and for illusory conjunctions, both in terms of raw detection scores and in terms of perceptual discriminability (dr scores). In Experiment 1, displays included either rectangles or triangles. In the first case, the target was a cross; in the second case, it was a Star of David. A hemifield x size interaction was observed both on correct detections and on associated discriminability. Yet, no such interaction was obtained for illusory conjunctions or for associated d’ scores. In Experiment 2, the two types of forms were presented simultaneously, with the small ones either inside or outside the large ones. No laterality effects were observed. Some implications of these data for both hemispheric asymmetry and feature integration issues are discussed. The results suggest that early preattentive processes of feature extraction are not lateralized, whereas some integrative mechanisms, such as Treisman’s (1988) focal attention, may operate differently in the two hemispheres.     

Search behaviour of cats (Felis catus) in an invisible displacement test: cognition and experience

An invisible displacement test was administered to cats in order to test the hypothesis that search behaviour in this species is influenced by their limited capacity for object permanence as well as by their previous experience with the environment. Experiment 1 compared three groups of cats in a five-choice hiding task in which the hiding places could be discriminated by their spatial positions. Two groups received a visible displacement training before the invisible displacement test and one group did not. Experiment 2 compared two groups of trained subjects in the same task, but the hiding places could be discriminated by spatial and visual cues. The results confirmed that cats are unable to solve problems with invisible displacements. The visible displacement training improved their performance, but was not sufficient to make them succeed. Experience with the hiding potential of the covers also gives more persistence to search behaviour. Finally, the distribution of search attempts is not determined by the proximity to the target and is influenced only partially by the subjects' previous experience. Like Stage 5 infants, cats rely mainly on their immediate perception. They search for an object in the last location they have seen it disappear or under the nearest cover from this location.     

Changes in information as a function of a culturally appropriate smoking cessation community intervention for Hispanics

Tested a 7-month, media-based, community intervention among Hispanics in San Francisco designed to change levels of information on the damaging effects of cigarette smoking and on the availability of culturally appropriate cessation services. Three community-wide surveys of Hispanics were conducted with independent random samples, two as baselines (n = 1,660 and 2,053) and one postintervention (n = 1,965). Results showed that changes in the level of awareness of cessation services had taken place after implementation of the intervention. Furthermore, those changes took place primarily among the less acculturated Spanish-speaking Hispanics who were the target of the intervention. The changes in information reported here demonstrate that a culturally appropriate information dissemination campaign that utilizes multiple channels can produce changes in a community's level of information even when the campaign is implemented for a relatively short period.     

Tracks and affordances: The sources of a physical ontology

How is meaning assigned to those terms in a theory which are remote from direct observational instantiation? Models and analogies play a role, but close examination of theories in high energy physics shows that the design of experimental apparatus also influences the interpretation of such terms. Certain apparatus favours certain kinds of effects, and this affects the way mathematical theories are interpreted. In particular track producing apparatus becomes involved with theories in which photonic terms are picked out in the theory. A further conceptual constraint is thus introduced. It is argued that this situation favours the interpretation of dispositional properties as affordances rather than as simple dispositions.     

The role accorded to the public by philosophers of science 1

The role accorded to the public by scientists and philosophers of science has undergone an essential historical change in the last three centuries. Public participation in (witnessing of) scientific experiments was considered an important requirement for 17th century experimenters (e.g. for Boyle or Pascal). The cognitive role played by lay persons was later substantially downgraded; witnessing went out of fashion, while science became more and more esoteric and a matter for experts only. Part of this process was that all scientific disciplines became intensively compartmentalized and in consequence a rather puzzling or even paradoxical situation appeared: that the scientists themselves were and are being reduced epistemically to the status of lay persons, outside of their proper field of expertise (as was pointed out by J. Hardwig). The paper deals with some cognitive aspects of this historical process.     

信号检测论方法引入集值统计试验

集值统计是模糊数学方法的应用,信号检测论之评价法与有无法实验满足集值统计条件,可用集值统计的程度函数表示辨别力或感受性的大小。本文提出两种计算程度函数的数学模型:(1)a=1/K[∑a_(k1·CP_(k1)(Y/SN)+∑a_(k2)·CP_(k2)(Y/N)],(2)f(u)=1/2[∑a_(k1)·P_(k1)(Y/SN)+∑a_(k2)·P_(k2)(Y/N)]。试验结果证实两种模型所计算的程度函数与信号检测论方法所计算的辨别力指数d’有高相关(r_(ad’)=0.842,r_f(u)d’=0.953、n=67),程度函数与d’一样,不仅可以作为辨别力的指标,而且可将判断标准与辨别力分开,不同的是程度函数用β=a_N/a_(SN)或β=f_N(u)/f_(SN)(U)计算的判断标准是一次性综合判断。此点不同于信号检测论可对每一个类别反应的判断标准进行计算。程度函数与d’的计算都利用了对信号与噪音的反应信息。除上述二者的共同之处外,程度函数比d’还具有以下一些优越性:(1)程度函数应用集值统计,无须信号检测论要求对信号与噪音的感觉分布为正态的基本假设,可认为是非参数的方法;(2)可克服信号检测论方法不同判断标准下d’不稳定又难以解释的困难;(3)可适当地减少试验次数;(4)程度函数取值在0-1之间,易于形成量表值方便比较,意义清晰、明确;(5)更符合心理判断的实际状态。     

汉语句子的多层次分析

本文试图建立一个中文句子分析的计算机模型。在该模型中,句法、语义信息对中文句子的多层次分析是同等重要的。为此,我们提出了一些语义规则,利用这些规则可将语义关系综合进句法和词典,使该模型能同时进行不同层次的加工。对汉语一些典型句型的应用表明,该模型是行之有效的。