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81.
人类颜色视觉的计算理论   总被引:2,自引:0,他引:2  
该文有机地结合了计算视觉理论和生态学视觉理论,指出颜色信息处理的根本任务是检测环境中的光不变量。在此基础上,作者提出了颜色视觉的计算理论以及计算理论本身的生物学标准。初级视觉计算是典型的不适定问题,动物的视觉系统则利用视环境中存在的条件将该不适定问题转化为定解问题。本文引入颜色视觉计算的免要条件,客观性约束,以及颜色认知的神经表象,证明了上述约束下颜色算法的存在性。本文给出了构造颜色知觉的基本假设。同时,该文还讨论了与上述问题密切相关的几个基本问题:神经表象的完备性,主观色觉的客观性,明度知觉和颜色知觉的统一,人类主观色觉的实现方式。  相似文献   
82.
场依存性与独立性认知方式对视动错觉的影响   总被引:4,自引:0,他引:4  
为探讨认知方式对视动性错觉的影响,对100名男性军校学员进行了棒框测验,15名高分者和15名低分者分别作为场依存组和场独立组。每名被试随机给予一系列视动阶跃刺激(5,10,15,20,30,40,60,80,100,120度/秒),每个刺激持续20秒。记录被试视动错觉出现的潜伏期和错觉模糊量。研究结果表明:1.场依存组被试的错觉潜伏期短于场独立组,它与刺激速度呈幂函数关系,而场独立组潜伏期随刺激速度的增加呈直线下降;2.在5—120度/秒的范围内,两组被试错觉量回归成两条直线,两直线回归系数无显著性差异,而截距差别十分显著。因此,场依存性/独立性认知方式是视动错觉个体差异性的一种重要影响因素,它对军事飞行员的心理学选拔和训练有着重要的意义。  相似文献   
83.
Summary One of the functions of visual attention is the selection of object information. This seems to be in line with an influential group of attentional models that assume that attentional selection is space based. These models assume that the selection of an object in vision is realized by selection of the location of that object. Whether this relatively simple idea of space-based attention and the corresponding, more elaborated space-based models are sufficient to handle selected constraints and problems of object selection is the main issue of this article. The first step toward an answer is to describe the common computational structure of space-based attentional models. Two model classes will be distinguished: capacity-limited models (e.g., Treisman, 1988; LaBerge & Brown, 1989) and models that do not assume a capacity limitation (e. g., Van der Heijden, 1992). Next, three kinds of task and data on object selection are introduced that are especially challenging for space-based models. The first type of data refers to experiments that require selection between overlapping objects. The second type of data concerns the influence of early perceptual grouping - a strong object-defining factor- on late response competition, and the third type consists of a selection task in which a high-level (semantic) attribute defines an object and controls selection. In all three cases, problems of space-based models are analyzed and possible solutions are sketched. Finally, a brief evaluative summary is given.  相似文献   
84.
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.  相似文献   
85.
Two experiments evaluated the effect of commitment on paper recycling. Using an ABA design, Experiment 1 asked 24 individuals in a retirement home to sign a 4-week group commitment pledge to recycle paper. During this intervention, the subjects recycled 47% more paper than they had during baseline. They continued to recycle at this level during a 4-week follow-up period, when the group commitment was removed. Experiment 2 evaluated the relative effectiveness of group commitment, individual commitment, and token reinforcers on paper recycling in a college dormitory. The students in all three experimental conditions recycled from three to five times more paper than those in the control group during the 4-week intervention. However, in the 3-week follow-up period, when the treatments were removed, only the individually committed subjects continued to recycle significantly more paper than the controls.  相似文献   
86.
Impact of practice on speed of mental rotation   总被引:1,自引:0,他引:1  
We tested 11- and 20-year-olds on 3360 trials of a mental rotation task in which they judged if stimuli presented in different orientations were letters or mirror images of letters. Children's and adults' processing times decreased substantially over practice. These changes were well characterized by hyperbolic and power functions in which most of the parameters of those functions were constrained to adults' values. Performance on two transfer tasks, mental rotation of letter-like characters and memory search for numbers, indicated that the practiced skill did not generalize to other domains. The results are discussed in terms of different mechanisms that might be responsible for the impact of practice.  相似文献   
87.
The present study investigates effects of different types of instructions (high-rate, interval, and minimal) during training with a fixed-interval schedule as a function of prior acquired temporal knowledge. A pretest was used to assess 4 1/2- and 6-year-old children's ability to understand the temporal parameters of a fixed-interval schedule of reinforcement. The results as a whole show that the control exerted by instructions given by the experimenter or elaborated by the subjects themselves on fixed-interval performance of young children depends on the interaction of two factors: development of verbal self-control skills and mastery of knowledge required by the rules forming the instructions.  相似文献   
88.
The present study used a multitrait-multimethod technique [D.T. Campbell and D. W. Fiske (1959) “Convergent and Discriminant Validation by the Multitrait-Multimethod Matrix,” Psychological Bulletin, 56, 81–105] to examine Bem's [(1974) “The Measurement of Psychological Androgyny,” Journal of Consulting and Clinical Psychology, 42, 152–162] use of an instrumental-expressive dichotomy to conceptualize the Masculinity and Femininity scales of the Bem Sex Role Inventory as statistically orthogonal constructs. Results indicate that while perhaps reliable, masculinity and femininity lack clear convergent and discriminant validity. Therefore, Bem's contention that masculinity and femininity are orthogonal constructs is questioned. Results are discussed in light of trait- vs. method-driven research.  相似文献   
89.
Gender differences in health status and illness behavior have been explained in terms of sex roles and gender-related personality traits. It may be hypothesized that in a community that is committed to gender-negating ideology, where men and women alike participate in public life, and housework and child care largely collectivized, gender health differences will disappear. The kibbutz movement is committed to the ideology of the emancipation of women: women fully participate in the labor force and decision making. Nonetheless, women on the kibbutz are responsible for the housework and are concentrated in feminine occupations. The kibbutz, then, allows us to test the relationship between gender ideology and participation in public life vs. gender roles and tasks, and health. The health behavior, health status, and illness behavior of 230 members of two kibbutzim, one religious and one secular, were studied. Men and women report similar health status and illness behavior; parental status is not related to health; and marital status is related to psychological distress only. Similar patterns were observed for the secular kibbutz and the religious one despite the more traditional division of labor in the latter.Medical student, supported by the National Fund for Medical Education, 35 Kneeland Street, Boston, MA 02111.  相似文献   
90.
比较短尾猴和恒河猴的社会行为模式   总被引:2,自引:0,他引:2  
短尾猴和恒河猴同是猴科猕猴属中两个不同的物种。从习性学的观点看,它们的社会行为模式应是大同而小异的。作者通过对生活在自然栖息地和实验笼内短尾猴所观察到的行为模式,同文献中已公认的恒河猴的行为模式进行比较后发现,这两种动物的社会行为模式虽然在基本上是相似的,但也有明显的差异。有的是行为模式相同,社会含意不尽相同;有的是社会含意相同,模式不同;也有的模式只是短尾猴有,而恒河猴没有。本文把初步观察到的7种不同情况列出。  相似文献   
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