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241.
Many studies of ADHD have shown that the problems associated with the disorder continue into adolescence and beyond for 10% to 60% of patients. The present study assesses several aspects of college adjustment, social skills, and self-esteem in a nonreferred sample of college students meeting criteria for a Diagnostic and Statistical Manual of Mental Disorders (4th ed.) diagnosis of ADHD. Twenty-one undergraduate students with symptoms of ADHD are compared to 20 students without significant ADHD symptoms, who match the ADHD students on age, gender, and grade point average. Students with ADHD symptoms show decreased functioning in several areas of college adjustment as well as lower levels of self-reported social skills and self-esteem. The results also suggest that the relation between ADHD and college adjustment is partially mediated by self-reported levels of self-esteem. 相似文献
242.
Böckenholt U 《心理学方法》2005,10(1):65-83
Markov models provide a general framework for analyzing and interpreting time dependencies in psychological applications. Recent work extended Markov models to the case of latent states because frequently psychological states are not directly observable and subject to measurement error. This article presents a further generalization of latent Markov models to allow for the analysis of rating data that are collected at arbitrary points in time. This extension offers new ways of investigating change processes by focusing explicitly on the durations that are spent in latent states. In an experience sampling application the author shows that such duration analyses can provide valuable insights about chronometric features of emotions. 相似文献
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244.
Teaching research ethics: Can web-based instruction satisfy appropriate pedagogical objectives? 总被引:1,自引:1,他引:0
Schrag B 《Science and engineering ethics》2005,11(3):347-366
Ethical tasks faced by researchers in science and engineering as they engage in research include recognition of moral problems in their practice, finding solutions to those moral problems, judging moral actions and engaging in preventive ethics. Given these issues, appropriate pedagogical objectives for research ethics education include (1) teaching researchers to recognize moral issues in their research, (2) teaching researchers to solve practical moral problems in their research from the perspective of the moral agent, (3) teaching researchers how to make moral judgments about actions, and (4) learning to engage in preventive ethics. If web-based research ethics education is intended to be adequate and sufficient for research ethics education, then it must meet those objectives. However there are reasons to be skeptical that it can. 相似文献
245.
Most studies of animal tool use require subjects to use one object to gain access to a food reward. In many real world situations, however, animals perform more than one action in sequence to achieve their goals. Of theoretical interest is whether animals have the cognitive capacity to recognize the relationship between consecutive action sequences in which there may be one overall goal and several subgoals. Here we ask if cotton-top tamarins, a species that in captivity uses tools to solve means-end problems, can go one step further and use a sequence of tools (means) to obtain food (end). We first trained subjects to use a pulling tool to obtain a food reward. After this initial training, subjects were presented with problems in which one tool had to be used in combination with a second in order to obtain food. Subjects showed great difficulty when two tools were required to obtain the food reward. Although subjects attended to the connection between the tool and food reward, they ignored the physical connection between the two tools. After training on a two-tool problem, we presented subjects with a series of transfer tests to explore if they would generalize to new types of connections between the tools. Subjects readily transferred to new connections. Our results therefore provide the first evidence to date that tamarins can learn to solve problems involving two tools, but that they do so only with sufficient training. 相似文献
246.
The transmission of tool use is a rare event in monkeys. Such an event arose in a group of semi-free-ranging Tonkean macaques (Macaca tonkeana) in which leaning a pole against the parks fence (branch leaning) appeared and spread to several males. This prompted us to test individual and social learning of this behavior in seven young males. In the first experiment, three males learned individually to obtain a food reward using a wooden pole as a climbing tool. They began using the pole to retrieve the reward only when they could alternatively experience acting on the object and reaching the target. In a second experiment, we first tested whether four other subjects could learn branch leaning after having observed a group-mate performing the task. Despite repeated opportunities to observe the demonstrator, they did not learn to use the pole as a tool. Hence we exposed the latter subjects to individual learning trials and they succeeded in the task. Tool use was not transmitted in the experimental situation, which contrasts with observations in the park. We can conclude that the subjects were not able to recognize the target as such. It is possible that they recognized it and learned the task individually when we alternated the opportunity to act upon the object and to reach the reward. This suggests that these macaques could then have associated the action they exercised upon the pole and the use of the pole as a means to reach the reward. 相似文献
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248.
Hoffmaster B 《The American journal of bioethics : AJOB》2005,5(3):50-1; discussion W10-2
249.
Recent findings are reviewed indicating that upper alpha oscillations - when analyzed with appropriate time/ frequency resolution - show a similar physiological reactivity as theta in working memory tasks. Comparable to theta, a load dependent increase in power can be observed during retention and increased evoked activity during retrieval. During retrieval attempts theta behaves like a traveling wave spreading from anterior to posterior sites. During actual retrieval, however, evoked upper alpha becomes transiently nested in theta. We suggest that theta reflects working memory functions whereas upper alpha may be important for the reactivation of long-term memory codes in short-term memory. 相似文献
250.
Three theoretical models have been proposed to represent self-concept: (a) unidimensional; (b) multidimensional; (c) multidimensional hierarchical. Inventories have been developed under each of the three competing theoretical models; which model best represents self-concept is unclear. Typically, self-concept construct validation has utilized various approaches including correlational, multitrait-multimethod, and factor analytic methods. Another method, however, for assessing validity would be to determine the consequences of score interpretations using different measures specific to each of the theoretical models. This paper examined Messick's notion (1989) of the validity of test-score interpretations as applied to three of the most widely used measures derived under each of the three different theoretical models of self-concept. Results suggest that overall multidimensional measures are more consistent in classifying individual's self-concept than unidimensional measures. 相似文献