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31.
Using a hybrid paradigm of a contextual cuing task and a probe detection task, we tested whether or not contextually new objects can be prioritized in visual search. After several hundred visual search practice trials with repeated and nonrepeated layouts, an additional distractor that was contextually new was presented in the repeated layouts. The results showed that detection of probe dots appearing at the location of a search target was faster in the repeated than in the nonrepeated layouts. More importantly, detection of probe dots at the new object locations was as fast as that of probe dots at the target locations in repeated layouts, suggesting that the attentional system implicitly prioritizes the processing of a location where a change in contextual information has occurred.  相似文献   
32.
This study examined the relationship between depressive symptoms and bias in the prediction of future life events. Responding to internet announcements, 153 participants varying widely in self-reported depression symptom severity estimated the probability of 40 events occurring over the succeeding 30 days. After the 30-day period, participants reported which events occurred. Optimistic/pessimistic biases were related to level of depressive symptoms. A non-significant optimistic bias characterized participants with low depressive symptoms whereas a significant pessimistic bias characterized participants with high depressive symptoms. Those reporting mild symptoms did not exhibit a systematic pessimistic or optimistic bias. General imprecision in predictions for undesirable events was associated with depressive symptoms. These findings suggest that depression is associated with pessimistic bias rather than accuracy in judgment.  相似文献   
33.
In almost all studies of bimanual movements with same and different amplitudes, the difference between amplitudes has been confounded with a difference between endpoint locations. The present authors varied those parameters orthogonally. In addition, they presented target locations on the surface on which the movements were produced (direct cues) and on a monitor (indirect cues). Participants' (N = 12) reaction times were longer when both amplitudes and endpoint locations differed than when they were the same. Intermanual amplitude correlations were reduced whenever 1 of the movement parameters differed for the 2 hands; only when cues were presented on the monitor was the amplitude correlation further reduced when both movement parameters were different. The results indicate that structural constraints on bimanual movements take effect on both amplitudes and endpoint locations. The relative importance of those 2 parameters is largely independent of the type of cue.  相似文献   
34.
Social discounting   总被引:1,自引:0,他引:1  
The amount of money a person was willing to forgo in order to give 75 dollars to another person decreased as a hyperbolic function of the perceived social distance between them. Similar hyperbolic functions have previously been shown to describe both time and probability discounting.  相似文献   
35.
本世纪六十年代资产阶级科学哲学演变的特点是同在此以前占统治地位的实证主义坚决分道扬镳。“在现代自然科学和社会科学的哲学中,主要倾向是反实证主义”——西方现代逻辑学-方法论的刊物上常常这样说。对这一现象进行历史和哲学的  相似文献   
36.
The effects of the color of a personal computer screen on work performance, psychological mood, and autonomic response were investigated. 24 subjects were asked to perform visual tasks presented on the computer display. Three types of computer monitor, which were colored red, blue, or beige, were employed to present visual cognitive tasks. The mood measure, the Japanese Stress Arousal Check List, and heart rate measurement were administered before and after work on each color of computer monitor. Analysis of a low-demand task (Exp. 1) showed that the red computer monitor reduced visual task performance compared to that with the blue, while the blue monitor decreased visual task performance on a high-demand task (Exp. 2). The color of the monitor did not affect mood or heart rate. Based on these findings, the effect of the color of environmental cues on work was discussed.  相似文献   
37.
The authors performed a behavioral study of the complexity of left-hand finger movements in classical guitar playing. Six professional guitarists played movement sequences in a fixed tempo. Left-hand finger movements were recorded in 3 dimensions, and the guitar sound was recorded synchronously. Assuming that performers prefer to avoid extreme joint angles when moving, the authors hypothesized 3 complexity factors. The results showed differential effects of the complexity factors on the performance measures and on participants' judgments of complexity. The results demonstrated that keeping the joints in the middle of their range is an important principle in guitar playing, and players exploit the available tolerance in timing and placement of the left-hand fingers to control the acoustic output variability.  相似文献   
38.
Xenotransplantation, or the use of animal cells, tissues and organs for humans, has been promoted as an important solution to the worldwide shortage of organs. While scientific studies continue to be done to address problems of rejection and the possibility of animal-to-human virus transfer, socio-ethical and legal questions have also been raised around informed consent, life-long monitoring, animal welfare and animal rights, and appropriate regulatory practices. Many calls have also been made to consult publics before policy decisions are made. This paper describes the Canadian public consultation process on xenotransplantation carried out by the Canadian Public Health Association in an arm’s length process from Health Canada, the ministry overseeing government health policy and regulation. Focusing on six citizen fora conducted around the country patterned after the citizen jury deliberative approach, the paper describes the citizen panelists’ recommendations to hold off on proceeding with clinical trials and the rationales behind this recommendation. The consultation process is discussed in the context of constructive technology assessment, a framework which argues for broader input into earlier stages of technology innovation, particularly at the technology design stage. This study was supported by a grant to the first author from the Social Sciences and Humanities Research Council in Canada.  相似文献   
39.
The influence of a genetic risk factor, apolipoprotein E (apoE) epsilon4 variant, was assessed in older adults aged 70 to 94 on 3 occasions over 7 years. The results of latent growth curve analyses are reported for individuals genotyped for apoE at the 2nd measurement occasion (n = 601) and for a subsample of individuals without probable or definite dementia during the 1st or 2nd occasion (n = 434). ApoE-epsilon4 status was a significant predictor of level and change in memory performance and change in speed performance in the full sample, and of initial level and change in memory performance in the nondemented subsample. These results support previous findings that apoE-epsilon4 is associated with accelerated memory deterioration in individuals without clinical dementia.  相似文献   
40.
Shevrin H  Ghannam JH  Libet B 《Consciousness and cognition》2002,11(2):334-41; discussion 342-46
In previous research Libet (1966) discovered that a critical time period for neural activation is necessary in order for a stimulus to become conscious. This necessary time period varies from subject to subject. In this current study, six subjects for whom the time for neural activation of consciousness had been previously determined were administered a battery of psychological tests on the basis of which ratings were made of degree of repressiveness. As hypothesized, repressive subjects had a longer critical time period for neural activation of consciousness, suggesting the possibility that this neurophysiological time factor is a necessary condition for the development of repression.  相似文献   
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