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971.
To examine the acquisition of voluntary control of a novel muscular activity from the initial stage to the self-control stage, the m. auricularis posterior, which had generally degenerated and had nearly lost its function of drawing an auricle backward in the human body, was selected as a target muscle to be studied. One female undergraduate student who could not move her auricles intentionally was required to activate her left m. auricularis posterior and underwent rest, pretest, training, and posttest sessions once a day for five days. At the subject's request, the electromyograph (EMG) from her left m. auricularis posterior on an oscillograph was provided for her as the feedback signal on each training trial. The picture of her left ear on television was handled in the same way. The EMG measures indicated that the subject could learn to activate her left m. auricularis posterior differentially. The number of training trials on which the subject requested the feedback signals suggested that EMG feedback signal was more useful to her than the video and that the usefulness of the feedback signals varied as the training sessions advanced. It was also concluded from analysis of the self-report data that the acquisition process of self-control of a novel muscular activity could be divided into at least four stages.  相似文献   
972.
Dynamic attending and responses to time   总被引:6,自引:0,他引:6  
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973.
Visual search and stimulus similarity   总被引:50,自引:0,他引:50  
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974.
The work on this paper was done in the research project V ra begrepp om spr k supported byHumanistisk-samhälls-vetenskapliga forskningsr det. I am indebted to Per Martin-Löf, Hans Ruin, Pär Segerdahl, and Sven Öhman for valuable comments on a previous version of this paper. Thanks to the comments of the anonymous referee I was able to improve some formulations in the paper.  相似文献   
975.
One interpretation of the doctrine of double effect (DDE) holds that in situations in which good can be secured for some only if others suffer harm, the pursuit of a good tends to be less acceptable when a resulting harm is intended as a means rather than when it is merely foreseen. The doctrine captures certain moral intuitions about pairs of cases which have the same consequential profiles but in which the character of the intention differs. Quinn examines the DDE using three pairs of contrasting cases, two of which are medical examples: the "Direction of Resources" case and the "Guinea Pig" case, both involving allocation of life-saving resources, and the "Craniotomy" case and the "Hysterectomy" case, both involving fetal vs. maternal life. He concludes that the DDE "embodies our sense that certain forms of forced strategic subordination are especially inappropriate among free and equal agents."  相似文献   
976.
Creating new memories that are quickly accessed and confidently held   总被引:1,自引:0,他引:1  
In two experiments involving a total of 542 subjects, a series of slides depicting a burglary was shown. After the initial event, subjects were exposed to one or more narratives about the event that contained some misinformation or neutral information about four critical details. Finally, subjects were tested on their memories of what they saw, and their reaction times and confidence levels were measured. When subjects took a standard test in which the misinformation item was a possible response option, they responded very quickly and confidently when making this incorrect choice. Misled subjects responded as quickly and confidently to these "unreal" memories as they did to their genuine memories. It does not seem, then, that the misinformation effect arises from a large proportion of subjects who must resolve a conflict between two memories when they are tested, a conflict that would be expected to take time. When subjects took a modified test in which the misinformation item was not a possible response, misled subjects were as accurate as were controls, but they responded more slowly, regardless of whether they ultimately chose the right or wrong option. These findings indicate that misinformation does introduce some form of interference not detected by a simple test of accuracy.  相似文献   
977.
Two experiments involving paired comparisons of numerical and nonnumerical expressions of uncertainty are reported. Subjects were timed under two opposing sets of instructions ("choose higher probability" vs. "choose lower probability"). Numerical comparisons were consistently faster and easier than their nonnumerical counterparts. Consistent distance and congruity effects were obtained, illustrating that both numerical and nonnumerical expressions of uncertainty contain subjective magnitude information, and suggesting that similar processes are employed in manipulating and comparing numerical and verbal terms. To account for the general pattern of results obtained, Holyoak's reference point model (1978) was generalized by explicitly including the vagueness of the nonnumerical expressions. This generalized model is based on the notion that probability expressions can be represented by membership functions (Wallsten, Budescu, Rapoport, Zwick, & Forsyth, 1986) from which measures of location for each word, and measures of overlap for each pair can be derived. A good level of fit was obtained for this model at the individual level.  相似文献   
978.
979.
The present 2 x 2 study deals with the influence of controllability and predictability of an aversive noise stimulus on a subsequent learning task. Eighty-four subjects participated in two experiments. In correspondence with the concept of learned helplessness, controllability was shown to be the dominant factor in the first experiment. In the second experiment, a modified test task was used in which both factors were shown to act in specific ways: The main influence of controllability is upon response measures (latency, omission), whereas unpredictability retardates learning of new predictive connections. The results are discussed in terms of contingency learning.  相似文献   
980.
Depressive characteristics of physically abused children   总被引:4,自引:0,他引:4  
Physically abused and nonabused children were compared on child-completed measures of depression, hopelessness, self-esteem, and locus of control. Results indicated that, in comparison with nonabused controls, abused children evidenced more depressive symptoms, heightened externality, lower self-esteem, and greater hopelessness about the future. Group differences in depressive symptomatology were not accounted for on the basis of differences in age, sex, race, gender, IQ, or socioeconomic status. Results replicate the results of Kazdin, Moser, Colbus, and Bell (1985) derived from a sample of physically abused psychiatric inpatients and extend the generality of these findings to abused children of nonpatient status. Implications of the findings for clinical interventions, theoretical models of child depression, and future research are discussed.The authors wish to thank Alvin Hadley and the staff of Franklin County Children Services.Appreciation is also extended to Dr. Charles Wenar.  相似文献   
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