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961.
The effects of preparatory weak muscular contraction (pre-tension) have been investigated in a number of previous studies using tasks with either simple or choice responses to measure the reaction time (RT). These studies suggested that optimal pre-tension performed prior to a motor response tends to shorten the RTs. Using a simple RT task in which participants performed a grip response to a visual stimulus, the present study compared the RTs between two pre-tension conditions (self-selection and constraint) to investigate the effects of different instructions for pre-tension. Under the self-selection condition, participants were asked to determine their optimal pre-tension levels while attempting to give responses as fast as possible. Under the constraint condition, the participants developed a pre-tension at a target force determined by the experimenter. The target force was set at the same level as the pre-tension level maintained under the self-selection. Despite the fact that the pre-tension level manipulated was the same for both conditions, the RTs were significantly shorter under self-selection than under constraint. Moreover, the present study showed a positive correlation coefficient between the proportion of shortening in RT and the variation of pre-tension level. This indicated a performance trade-off between the stability of pre-tension and RTs. The result suggests that shorter RTs that occur under self-selection are primarily mediated by mental factors, such as attention allocation, rather than by the effects of peripheral muscular preparation.  相似文献   
962.
Novice designers produced a sequence of sketches while inventing a logo for a novel brand of soft drink. The sketches were scored for the presence of specific objects, their local features and global composition. Self-assessment scores for each sketch and art critics' scores for the end products were collected. It was investigated whether the design evolves in an essentially random fashion or according to an overall heuristic. The results indicated a macrostructure in the evolution of the design, characterized by two stages. For the majority of participants, the first stage is marked by the introduction and modification of novel objects and their local and global aspects; the second stage is characterized by changes in their global composition. The minority that showed the better designs has a different strategy, in which most global changes were made in the beginning. Although participants did not consciously apply these strategies, their self-assessment scores reflect the stages of the process.  相似文献   
963.
Individuals with Alzheimer's disease (AD) often have problems in recognizing common objects. This visual agnosia may stem from difficulties in establishing appropriate visual boundaries between visually similar objects. In support of this hypothesis, showed that AD subjects have difficulties in establishing visual category boundaries between continuously graded shapes. In an attempt to investigate the neural basis of these impairments, the current study required a group of neurologically healthy elderly participants to categorically classify a series of ellipses varying in width while regional blood flow changes were measured using positron emission tomography (PET). Two categorization conditions were compared in order to isolate changes in cortical activity that dissociated the categorization of shapes situated either near or far from a category boundary that divided the width continuum. The participants produced a discontinuity in the probability and speed of categorizing the shapes at some point along the continuum, suggesting that the objects were classified into distinct categories. Moreover, a comparison of the PET scans obtained while the subjects were categorizing the shapes situated near vs. far form the category boundary revealed significant differences in cortical activity in the parietal and frontal brain areas. These findings suggest that both visuo-spatial and decision making mechanisms may be involved in establishing categorical distinctions between continuously graded stimuli. It is proposed that the functional role of the parietal and frontal cortical regions in establishing visual boundaries between categories of objects may be relevant for understanding object recognition impairments in AD.  相似文献   
964.
Women at greatest risk for hereditary breast and ovarian cancer may consider prophylactic removal of breasts or ovaries as a risk-reduction measure. This report describes uptake of risk-reduction mastectomy (RRM), risk-reduction oophorectomy (RRO), and related factors in 62 high-risk women who received genetic counseling. Seven (11%) participants underwent RRM and 13 (21%) underwent RRO. Of these women, 37% did not have BRCA testing, suggesting other factors influence decisions to undergo surgery. Women who had indicated (pre-genetic counseling) their intent not to have surgery chose not to have surgery. Information received during genetic counseling that women perceived as being most important for influencing risk-reduction surgery decisions was BRCA test result (positive or negative), followed by discussion of family cancer history. Reasons for indecision about risk-reduction surgery included genetic testing results, concerns about surgery, timing in life, and early menopause. The findings enhance our understanding of information that is helpful to women considering this surgery.  相似文献   
965.
There has always been confusion and disagreement about the nature of the terms archetype and complex in Jungian circles, not to mention non-Jungian ones. Another ongoing concern is whether Jung's concept of the archetype and complex can be justified in terms of current scientific research, most notably that of neurophysiologists and others interested in the brain and consciousness. This paper proposes a theory of the formation of complexes, namely, that they are created through self-organization within the brain/mind. Self-organization is a process typical of large complex systems, and is generally accepted to operate within the brain and to be important in its functioning. Examples of self-organization in biology are related to the psychic processes that form the complexes. It is then natural to define the archetype in terms of the complex, and the authors propose a definition of the archetype as an equivalence class of complexes. On this view, the archetype is an emergent property of the activity of the brain/mind, and is, appropriately, defined at the level at which it emerges. This definition is in line with the original development of Jung's ideas, in that he derived the concept of the archetype from his earlier discovery of the feeling-toned complex.  相似文献   
966.
We argue that considering only a few ‘big’ ethical decisions in any engineering design process — both in education and practice — only reinforces the mistaken idea of engineering design as a series of independent sub-problems. Using data collected in engineering design organisations over a seven year period, we show how an ethical component to engineering decisions is much more pervasive. We distinguish three types of ethical justification for engineering decisions: (1) consequential, (2) deontological or non-consequential, and (3) virtue-based. We find that although there is some evidence for engineering designers as ‘classic’ consequentialists, a more egocentric consequentialism would appear more fitting. We also explain how the idea of a ‘folk ethics’ — a justification in the second category that consciously weighs one thing with another — fits with the idea of the engineering design process as social negotiation rather than as technological progress.  相似文献   
967.
In response to the difficulty of teaching an increasingly large number of students who are ill prepared for the sort of abstract thinking and well-structured essay writing that are essential to the field of Philosophy, I have discovered a five-step method for teaching students in my Philosophy and Social Ethics course how to examine any ethical issue and write well-structured essays discussing the issue. Just as important, students are now required to take more responsibility for the learning process which, I believe, is an appropriate goal for a course in Ethics.  相似文献   
968.
The concept of science linked to the concept of community psychology requires adaptation. In the case of community psychology, science is public to citizens as well as to the scientist. The community psychologist, as scientist, works from the expectation that choices of topics, methods, and interpretation of findings are done in concert with representatives of the community. The following remarks offer 7 ways to keep vital the research of the community psychologist while contributing to robust and useful knowledge.  相似文献   
969.
不同ISI下异同判断的同反应启动效应   总被引:6,自引:1,他引:5  
通过改变刺激对中的第一个刺激消失到第二个刺激出现之间的间隔 (interstimulusinterval,简称ISI) ,并控制呈现的刺激前后试验不重复 ,分别进行不同形状白色图形的异同判断实验和不同颜色圆形的异同判断实验 ,系统地考察不同ISI下异同判断的同反应启动效应 ,研究异同判断的加工机制。两个实验均采用 2 (前次试验类型 :异、同 )× 2 (当前试验类型 :异、同 )× 6(ISI :1 0 0ms、2 0 0ms、30 0ms、40 0ms、50 0ms、60 0ms)重复测量设计。被试为2 1名大学本科生 ,其中男生 1 0名 ,女生 1 1名。结果发现 ,在两实验中的每一种ISI条件下 ,同反应后的试验的反应时均显著短于异反应后的试验的反应时 ,即表现出显著的同反应启动效应。实验的结果支持异同判断的双过程模型 ,并表明双加工机制可能是序列工作的  相似文献   
970.
Discounting of delayed rewards by pathological gamblers was compared to discounting of delayed rewards by matched control nongambling participants. All participants completed a hypothetical choice task in which they made repeated choices between dollars 1,000 available after a delay and an equal or lesser amount of money available immediately. The delay to the large amount of money was varied from 1 week to 10 years across conditions. Indifference points between immediate money and delayed money were identified at each delay condition by varying the amount of immediate money across choice trials. For the majority of participants, indifference points decreased monotonically across delays. Overall, gamblers discounted the delayed rewards more steeply than did control participants.  相似文献   
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