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101.
Eighty Ss were first tested for base-level response to a pain-producing stimulus and then were re-tested on the same pain stimulus after receiving 1 of 8 experimental treatments. The 8 treatments were arranged in a 2 x 2 x 2 factorial design: presence or absence of hypnotic induction procedure; presence or absence of instructions for anesthesia; and presence or absence of demands for honest reports. Neither the hypnotic-induction procedure nor the demands for honesty affected the Ss'reports of the degree of pain experienced. The anesthesia instructions--"think of the hand as numb and insensitive as if it were a piece of rubber..."--produced an equal degree of pain reduction in hypnotic and non-hypnotic Ss and in Ss who were and those who were not exposed to demands for honesty. The results indicate that (a) Ss' reports of pain are less affected by demands for honesty and are more closely related to their actual experiences than has been previously assumed and (b) instructions which direct Ss to exercise cognitive control over painful sensory input are effective (with or without 'hypnosis') in reducing the experience of pain.  相似文献   
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The relative effectiveness of explicit instruction, guided discovery, and discovery learning techniques in enhancing anticipation skill in young, intermediate-level tennis players was examined. Performance was assessed pre- and postintervention, during acquisition, and under transfer conditions designed to elicit anxiety through the use of laboratory and on-court measures. The 3 intervention groups improved from pre- to posttest compared with a control group (n = 8), highlighting the benefits of perceptual-cognitive training. Participants in the explicit (n = 8) and guided discovery (n = 10) groups improved their performance during acquisition at a faster rate than did the discovery learning (n = 7) group. However, the explicit group showed a significant decrement in performance when tested under anxiety provoking conditions compared with the guided discovery and discovery learning groups. Although training facilitated anticipation skill, irrespective of the type of instruction used in this experiment, guided discovery methods are recommended for expediency in learning and resilience under pressure.  相似文献   
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Wade NJ 《Perception》2004,33(7):869-889
Visual neuroscience is considered to be a contemporary concern, based in large part on relating characteristics of neural functioning to visual experience. It presupposes a detailed knowledge of neural activity for which the neuron doctrine is a fundamental tenet. However, long before either the neuron doctrine had been advanced or the nerve cell had been described, attempts were made to estimate the dimensions of nerve fibres from measures of visual resolution. In the seventeenth century, the microscopes of Hooke and van Leeuwenhoek were unable to resolve structures as small as nerves adequately. However, it was not Hooke's microscope that led to an estimate of the dimensions of nerve fibres but his experiments on the limits of visual resolution. Hooke determined that a separation of one minute of arc was the minimum that could normally be seen. Descartes had earlier speculated that the retina consisted of the terminations of fibres of the optic nerve, and that their size defined the limits of what could be seen. Estimates of the diameters of nerve fibres were made on the basis of human visual acuity by Porterfield in 1738; he calculated the diameters of nerve fibres in the retina as one 7200th part of an inch (0.0035 mm), based on the resolution of one minute of arc as the minimum visible. In the same year, Jurin questioned the reliability of such estimates because of variations in visual resolution with different stimuli. The measurement of visual acuity was refined by Mayer in 1755, with dots, gratings, and grids used as stimuli. In the 1830s, Treviranus fused the microscopic and acuity approaches to determine the dimensions of nerve fibres. His indirect estimates of the dimensions of retinal fibres were close to those derived from microscopic observation. However, the suggestion that the retina consisted of terminations of nerve fibres influenced his detailed illustrations of its microscopic structure. Contrary to the situation that obtained after the microscopic structure of the retina had been established, a function of vision (acuity) was used to determine the dimensions of the structures (retinal elements) that were thought to mediate it.  相似文献   
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Throughout the U.S., state laws require professionals who work with children to report cases of suspected child abuse to child protection services. Both practically and conceptually, however, significant problems arise from a lack of clarity regarding the threshold that has been set for reporting. Specifically, there is no consensus as to what constitutes reasonable suspicion, and little direction for how mandated reporters should gauge their legal and professional responsibilities when they harbor suspicion. In this paper we outline the context of the problem, discuss the nature and scope of its conceptual underpinnings, and offer recommendations for moving towards a concrete, practical solution.  相似文献   
106.
The Parents Matter! Program (PMP) has developed three interventions for parents of 4th and 5th grade African-American children (9–12 years old). The overarching goal of all three interventions is to provide parents with knowledge, skills, and support for enhancing their efforts to raise healthy children. The interventions are: (1) Enhanced Communication and Parenting (five 2 -hour sessions), (2) Brief Communication and Parenting (single 2 -hour session), and (3) General Health (single 2 -hour session). This article discusses the development of these interventions, presents an overview of the content of each intervention, and discusses issues related to the facilitation/presentation of these interventions.  相似文献   
107.
Senior capstone design and ethics: A bridge to the professional world   总被引:1,自引:1,他引:0  
A senior level capstone design experience has been developed and offered with a particular emphasis on many of the professional issues raised in Accreditation Board for Engineering and Technology (ABET) Engineering Criterion IV. The course has sought to develop student awareness of the ethical foundation of the engineering profession, the global and societal framework within which engineers practice, and the environmental impact on engineering. The capstone design course also focused upon improving the technical communications skills of the graduating senior class with both extensive instruction in writing and multiple workshops dealing with the art of making an effective oral presentation. The effectiveness of the design course was assessed using Kirkpatrick’s model for evaluating training programs. An earlier version of this paper was presented at the “Ethics and Social Responsibility in Engineering and Technology” meeting, New Orleans, 2003.  相似文献   
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Previous researchers have proposed that because of their slow muscle-response latencies, 1- to 2-year-old children are unable to control hip-dominant postural responses when responding to balance threats (G. McCollum & T. Leen, 1989). To test that proposition, the authors exposed 41 children to backward support-surface translations and recorded muscle activations and movement kinematics. Children between 10 months and 10 years of age stood on a platform that was unexpectedly moved. Passive hip-dominant responses were observed among the least experienced walkers. In contrast, older children produced an active response, signified by higher levels of abdominal and quadriceps muscle activity and accompanied by larger hip flexor torques. Greater success in withstanding large magnitudes of perturbations were associated with actively generated hip responses.  相似文献   
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