基于示例学习的认知技能获得的研究

本文简要介绍了基于示例学习的认知技能获得的研究,涉及的问题包括示例学习的过程、影响认知技能获得的因素、认知技能获得中的练习和迁移等、在文章的最后,对这一领域的研究趋势进行了展望。     

Change in visually perceived eye level without change in perceived pitch

Both the physical elevation that appears to correspond to eye level and the visually perceived pitch of a visual field are linear functions of the physical pitch of a normally illuminated, complexly structured visual field. One of the possible bases for the large effect of physical pitch on the elevation of visually perceived eye level (VPEL) is that the visual field generates a mental representation which specifies spatial coordinates and these determine the VPEL elevation ('implicit-surface model'; ISM). The influence on the elevation of VPEL is nearly as large when the visual field contains either one or two long pitched-from-vertical or rolled-from-vertical lines in otherwise total darkness as when it consists of a well-illuminated and complexly structured pitched room (L Matin and W Li, 1994 Vision Research 34 311-330), and, in order to examine the ISM, we employed a rolled-from-vertical, two-line configuration within a frontoparallel plane viewed in otherwise total darkness. Measurements of visually perceived pitch were made by a manual matching procedure and VPEL measurements were made by the psychophysical setting of the elevation of a small visual target to appear at eye level while each of three subjects viewed the two-line configuration at each of three horizontal eccentricities with the configuration at each of seven roll orientations. In direct contradiction to the ISM, the perceived pitch of the two-line configuration did not deviate significantly from the erect orientation ('vertical') for any roll at any eccentricity, but the elevation of VPEL changed systematically with the roll of the configuration both at left and at right eccentricities, and did not change at all with the two-line configuration centered on the median plane. Consistent with our previous work and with our previous interpretation regarding the basis for VPEL (L Matin and W Li, 1994 Vision Research 34 2577-2598), the variation of VPEL for the two-line visual field equals the average of the VPEL variations produced by viewing each of the single lines separately.     

Does segregation by colour/luminance facilitate the detection of structure-from-motion in noise?

The aim in the experiments was to examine whether the detection of structure-from-motion (SFM) in noise was facilitated when target and noise were segregated by colour and/or luminance polarity. The SFM target was a rotating 'V-shape' structure simulated with limited-lifetime Gaussian micropatterns and embedded in random-motion noise. Threshold levels of V-shape slant were measured for stimuli in which target and noise were segregated or unsegregated by colour/luminance, and under two conditions, with and without static form cues to the SFM target. The presence or absence of static form cues to the SFM target was manipulated by varying the relative numbers of micropatterns in target and noise. In the absence of static form cues, segregation of target and noise by colour and/or luminance polarity did not facilitate target detection, even when subjects knew which micropatterns belonged to the target. On the other hand, when static form cues were present, segregation improved performance. These results imply that SFM processing is 'form-cue invariant' except when the target form is immediately identifiable in the static view of the stimulus. The significance of the results for understanding the role of colour vision in breaking camouflage and in 'grouping' is discussed.     

Looming Responses to Obstacles and Apertures: The Role of Accretion and Deletion of Background Texture

Successful navigation in the world requires differentiating an obstacle in one's path from an aperture through which one could pass. An approaching obstacle is specified by texture expansion within the obstacle's contour and the deletion of background texture outside the object. In contrast, an approaching aperture contains texture expansion within the aperture's frame and accretion of background texture within the aperture's contour. This study investigated 3- to 5-month-old infants' discrimination of obstacles from apertures, examining eyeblink responses to the movement of both kinds of objects against backgrounds varying in salience. Obstacles produced stronger looming reactions than apertures, and the salience of the background influenced responses to apertures but not obstacles. These findings imply that infants differentiate obstacles from apertures based on their relative patterns of accretion versus deletion of background texture, and suggest that infants recognize the functional consequences of contact with these objects.     

多个非线索化位置易代的一项实验研究

现在采用返回抑制范式所进行的空间非信息线索作用的研究,大多以非线索化位置反应时为参照,发现线索化位置的反应先易化后抑制。后者即返回抑制。本研究采用在返回抑制范式上增设中性线索化条件的方法,发现当靶子可以出现的位置为四个时,相对于中性线索化条件,非线索化位置反应快。这种非线索化位置的易化作用是独立存在的,它能使生物体尽快地对出现在多个非线索化位置的靶子作出反应。     

刺激属性对内隐社会知觉的影响

本文通过选择不同词性（消极词、积极词和中性词）的双字词64个,主要对“刺激属性”变量进行了实验操作;采用“意识过滤”技术和速示辨认测验对内隐社会知觉的特点进行了考察;结果发现,实验材料的笔划数和被试的性别对内隐社会知觉没有影响,刺激的特性和刺激的启动作用对内除社会知觉有显著的影响;同时还证明速示辨认测验不受意识的“污染”,将速示辨认作为内臆测验的方法是比较“纯净的”。     

时间顺序信息加工的实验研究

该研究运用Ｇｌｕｃｋｓｂｅｒｇ和ＭｃＣｌｏｓｋｅｙ（１９８１）的问答模型,通过两个实验检查了项目的时序信息是通过项目学习时的时序编码获得的,还是在项目提取时建构的;时序加工是自动的,还是控制的两个问题。结果表明：项目的时序信息是通过项目学习时的时序编码获得的,而不是在项目提取时建构的;时序信息的编码是控制的。     

胎教音乐对胎儿影响的实验研究

该项研究从三个方面探讨了胎教音乐对胎儿的作用。结果发现：胎教音乐可以使胎动时间延长,并证明在胎儿后期即存在条件反射;胎儿出生后能够再认胎教音乐,说明在胎儿后期已经存在听觉记忆;胎儿的性别及神经活动类型是影响其对音乐反应的重要因素。该研究的意义在于：证明了胎儿期心理现象的存在。把对“胎儿期有无心理现象”的历史争论引入了心理学的实验过程。     

认知作业年老化的比较研究

用言语—操作和人机对话两种方式完成１２项认知作业年老化比较研究,被试２４２人,４６－７５岁。结果表明：（１）一些作业（符号数字、视觉数字广度、听觉数字广度、词对联想学习、图象自由回忆和无意图形再认）成绩随年老明显下降,另一些作业（图象分类、卡片分类、心算和矩阵填图）成绩不随年老明显降低;（２）再次验证心算、符号数字、数字鉴别和计数四项非词语性作业速度随年老进行性减慢。     

目标结构与学习动机

本文概述了目标结构理论的形成及发展,并进一步论述了在教学中不同的目标结构,导致学生间不间的相互关系,从而使学生形成不同的学习动机,取得不同的学业成就。竞争目标结构激发的是能力中心的动机系统;个体化目标结构激发的是任务掌握的动机系统;合作目标结构激发的是道德中心的动机系统。由此,我们认为在当前的教学实践中应重视合作目标结构的建立。