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Summary Network models of semantic memory assume implicitly or explicitly that the degree of activation of a node is a monotonic function of the total amount of excitation reaching that node from all sources. For example, the activation level of the node representing apple should be greater if it is receiving excitation due to the activation of the nodes for fruit and pear than if only one of these neighboring nodes is activated. This notion was tested by presenting semantic primes 80 ms or 320 ms before a letter string (e.g., apple or ipple) requiring a lexical decision. The prime stimuli consisted of a pair of simultaneous items that were identical in the single prime condition (e.g., fruit/fruit or pear/pear) or different in the double prime condition (e.g., fruit/pear or pear/fruit), and were either related (target = apple) or unrelated (target = copper) to the target, or neutral. As predicted by the summation of semantic activation assumption of network models there was a larger priming effect (in the 320 ms SOA condition) following the simultaneous activation of two related nodes than following the activation of only one node.This research was supported by grants to the first author from the Natural Sciences and Engineering Research Council of Canada. 相似文献
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High-resolution CRT displays are subject togeometric distortion: lines that are straight in the internal coordinates of the graphics software and hardware are curved when projected onto a plane in the observer’s line of sight. As the available resolution of CRT screens increases, it becomes more difficult to measure and correct for this distortion. We present a simple, highly accurate method for determining the mapping between internal coordinates and the viewing plane. It requires that an observer, using a calibration program, adjust triples of displayed points until they are collinear. A metal straightedge placed between the observer and the screen aids in this judgment. We describe the calibration of an IBM Enhanced Graphics Display in high-resolution mode (350 × 640 pixels), and illustrate how to use the estimated mapping to choose internal coordinates to draw undistorted figures that are accurate to within 0.5 pixel. The method can be used to assess or to correct the accuracy of visual displays. The method is relevant to experiments in spatial vision, spatial perception, perception of dot patterns, and any application in which geometrically accurate stimuli are required. 相似文献
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Lee Williams PhD Richard Bischoff MS Jacqueline Ludes MEd 《Contemporary Family Therapy》1992,14(4):309-322
With approximately one out of six married couples experiencing infertility, having a basic knowledge of infertility is important to marriage and family therapists. This paper presents important themes that infertile couples often struggle with and stresses the importance of having a biological, psychological, and social understanding of infertility. In addition, the paper suggests possible interventions that family therapists can use in helping infertile couples. 相似文献
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Adrienne Y. Lee 《Behavior research methods》1992,24(2):205-212
HyperCard was used to develop a simplified tutoring system whose principles were based on a learning theory, and a genetics tutoring system was evaluated experimentally. Learning was studied by examining immediate versus delayed feedback after an error was made. Such tutoring systems aid in psychological studies of learning, because experimental variables can be easily manipulated. HyperCard provides a good vehicle for tutoring system development, since it requires no extensive programming skills. 相似文献