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61.
This study examined the role of global processing speed in mediating age increases in auditory memory span in 5- to 13-year-olds. Children were tested on measures of memory span, processing speed, single-word speech rate, phonological sensitivity, and vocabulary. Structural equation modeling supported a model in which age-associated increases in processing speed predicted the availability of long-term memory phonological representations for redintegration processes. The availability of long-term phonological representations, in turn, explained variance in memory span. Maximum speech rate did not predict independent variance in memory span.  相似文献   
62.
Representation and working memory in early arithmetic   总被引:1,自引:0,他引:1  
Working memory has been implicated in the early acquisition of arithmetic skill, but the relations among different components of working memory, performance on different types of arithmetic problems, and development have not been explored. Preschool and Grade 1 children completed measures of phonological, visual-spatial, and central executive working memory, as well as nonverbal and verbal arithmetic problems, some of which included irrelevant information. For preschool children, accuracy was higher on nonverbal problems than on verbal problems, and the best and only unique predictor of performance on the standard nonverbal problems was visual-spatial working memory. This finding is consistent with the view that most preschoolers use a mental model for arithmetic that requires visual-spatial working memory. For Grade 1 children, performance was equivalent on nonverbal and verbal problems, and phonological working memory was the best predictor of performance on standard verbal problems. For both age groups, problems with added irrelevant information were substantially more difficult than standard problems, and in some cases measures of the central executive predicted performance. Assessing performance on different components of working memory in conjunction with different types of arithmetic problems provided new insights into the developing relations between working memory and how children do arithmetic.  相似文献   
63.
Critics of genetic discourse are concerned that deterministic and discriminatory views of genetics are increasingly becoming adopted. These views argue that current genetic discourse becomes a source of power whereby powerful institutions harm people with so-called “bad” genes. This essay argues that current analyses of the power of genetics discourse are grounded in an improper reading that disempowers patients. Deploying Michel Foucault's concept “care of the self,” this essay claims that genetics discourse is better understood as a way that patients take on power through rhetoric rather than a force that has power over patients. Through a close reading of the “My Family Health Portrait” program, this paper argues that patients experience a process of “subjection” wherein they become agents of and objects of genetics discourse both. This alternative mode of analyzing the power of genetics discourse has implications for our collective understanding of the operations of the care of the self and the uses of genetic information that we propose.  相似文献   
64.
Rodent models of motor skill learning include skilled forelimb reaching and acrobatic locomotor paradigms. This study characterizes motor skill learning in the accelerated rotarod task. Thirty Long-Evans rats (300-400 g) were trained on an accelerated rotarod (1cm/s(2)) over eight consecutive sessions (=days, 20 trials each). Improvement in rotarod velocities mastered before falling off the rod was observed within and between sessions (plateau after five sessions). Intrasession improvement was incompletely retained at the beginning of the next day's session. Over several training sessions, intrasession improvement diminished, suggesting a ceiling effect. After 1 week of pause, the rotarod skill was retained. Locomotor exercise in a running wheel for 30 min before the first rotarod session did not affect intrasession improvement. Running-wheel exposure for 6 days did not diminish the rate of rotarod skill learning (steepness of the learning curve) but improved overall performance (upward shift of curve). Video analysis of gait on the rotarod showed that rats developed a motor strategy by modifying their gait patterns during training. The data demonstrate that rotarod improvement is not the result of enhanced general locomotor ability or fitness, which are trained in the running wheel, but requires a change in the motor strategy to master the task. Accelerated rotarod training can be regarded a valid paradigm for motor skill learning over short (intrasession, minutes) and long time frames (intersession, days).  相似文献   
65.
The effects of hostility and a cold pressor stressor on the accuracy of facial affect perception were examined in the present experiment. A mechanism whereby physiological arousal level is mediated by systems which also mediate accuracy of an individual’s interpretation of affective cues is described. Right-handed participants were classified as high hostile (N=28) or low hostile (N=28) using the Cook Medley Hostility Scale. The high-hostile group met joint selection criteria. Only high-hostile participants who showed cardiovascular reactivity to the cold pressor, with systolic BP change exceeding the group mean were included. Groups were further subdivided into cold pressor and non-cold pressor test conditions. It was predicted that high-hostile men, relative to low-hostile men, would show decreased perceptual accuracy when presented with happy, angry, and neutral facial configurations within the left visual field (LVF). Results indicated that high-hostile men were less accurate than low-hostile men in the LVF. Further, pre-stress accuracy scores in the high-hostile men were similar to the post-stress accuracy scores of the low-hostile men. The lateralization of affective function and the role of physiological arousal in affective facial perception are discussed.  相似文献   
66.
The problem of constructing computational models of space that mimic those found in human spatial reasoning is addressed. This paper extends a formal model that addressed point objects in a 2D world to include the presence of line objects and barriers. The problem consists of determining an appropriate global model for the spatial configuration given a sequence of local views or observations. A formal model is proposed based on constraint network theory. The model leads to the identification of stable regions within which perceptual information about the environment changes slowly, and zones of transition within which the perceptual information changes more quickly. A special case of transition zones is a gateway, which may be viewed as a kind of discontinuity or singularity in the model. It is expected that the model obtained will be used to mimic human mental representations of navigable outdoor environments.  相似文献   
67.
Three hundred participants, including volunteers from an obsessional support group, filled in questionnaires relating to disgust sensitivity, health anxiety, anxiety, fear of death, fear of contamination and obsessionality as part of an investigation into the involvement of disgust sensitivity in types of obsessions. Overall, the data supported the hypothesis that a relationship does exist between disgust sensitivity and the targeted variables. A significant predictive relationship was found between disgust sensitivity and total scores on the obsessive compulsive inventory (OCI; Psychological Assessment 10 (1998) 206) for both frequency and distress of symptomatology. Disgust sensitivity scores were significantly related to health anxiety scores and general anxiety scores and to all the obsessional subscales, with the exception of hoarding. Additionally, multiple regression analyses revealed that disgust sensitivity may be more specifically related to washing compulsions: frequency of washing behaviour was best predicted by disgust sensitivity scores. Washing distress scores were best predicted by health anxiety scores, though disgust sensitivity entered in the second model. It is suggested that further research on the relationship between disgust sensitivity and obsessionality could be helpful in refining the theoretical understanding of obsessions.  相似文献   
68.
A 67 item self-report questionnaire called the Meta-Cognitive Beliefs Questionnaire (MCBQ) was developed to assess endorsement of beliefs about the importance of control and negative consequences associated with unwanted, ego-dystonic intrusive thoughts, images and impulses. The MCBQ and a battery of questionnaires that assessed symptoms and cognitions of worry, obsessive-compulsive disorder, anxiety, and depression were administered to large samples of undergraduate students. Beliefs about control of intrusive thoughts and perceived negative consequences due to uncontrolled mental intrusions had a unique significant relationship with obsessions, and to a lesser extent, worry. These findings are consistent with current cognitive behavioral theories that suggest an important role for meta-cognitive beliefs in the pathogenesis of obsessions.  相似文献   
69.
This study tested Annett's right-shift theory on spatial ability with two samples from China. The Vandenberg Mental Rotation Test (MRT), Edinburgh Handedness Inventory, and Family Handedness Questionnaire were administered to 266 high school students and 297 undergraduates. We found very few r++ or r-- among Chinese students. Most Chinese are either moderately right-handed or ambidextrous. Consistent with Casey's finding, we found using different methods to classify handedness leads to different conclusions. However, we did not find the effect of familial handedness that Casey found. Visual strategy is related to success on the MRT but handedness is not.  相似文献   
70.
卫生资源优化配置的伦理要求   总被引:2,自引:0,他引:2  
卫生资源是稀缺资源,卫生资源只有优化配置,才能达到我们的医学目的。卫生资源的优化配置的以公平为优先,坚持公平和效率相结合的原则。就目前所存在的和我们的医学目的不相适应的卫生资源配置方式的现状和主要问题进行分析,并提出了相应的改进方法。  相似文献   
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