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151.
Observers viewed the optical flow field of a rotating quadric surface patch and were required to match its perceived structure by adjusting the shape of a stereoscopically presented surface. In Experiment 1, the flow fields included rigid object rotations and constant flow fields with patterns of image acceleration that had no possible rigid interpretation. In performing their matches, observers had independent control of two parameters that determined the surface shape. One of these, called the shape characteristic, is defined as the ratio of the two principle curvatures and is independent of object size. The other, called curvedness, is defined as the sum of the squared principle curvatures and depends on the size of the object. Adjustments of shape characteristic were almost perfectly accurate for both motion conditions. Adjustments of curvedness, on the other hand, were systematically overestimated and were not highly correlated with the simulated curvedness of the depicted surface patch. In Experiment 2, the same flow fields were masked with a global pattern of curl, divergence, or shear, which disrupted the first-order spatial derivatives of the image velocity field, while leaving the second-order spatial derivatives invariant. The addition of these masks had only negligible effects on observers’ performance. These findings suggest that observers’ judgments of three-dimensional surface shape from motion are primarily determined by the second-order spatial derivatives of the instantaneous field of image displacements.  相似文献   
152.
In response to parental requests for assistance in dealing with adolescent problem children, three parent-child pairs were taught negotiation responses to hypothetical conflict situations using behavior rehearsal and social reinforcement. The negotiation process was separated into component behaviors that were practised during simulations by each youth and his parent under the direction of trainers. Results indicated that (a) the procedures were successful in training youths and their parents in negotiation behaviors that produced agreements to conflict situations, and (b) these behaviors generalized to actual conflict situations in subjects' homes.  相似文献   
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The "pre-delinquent" behaviors of six boys at Achievement Place, a community based family style behavior modification center for delinquents, were modified using token (points) reinforcement procedures. In Exp. I, point losses contingent on each minute late were effective in producing promptness at the evening meal. During the reversal phase, threats (which were not backed up with point losses) to reinstate the point consequences initially improved promptness but the last two of five threats were ineffective. In Exp. II, point consequences effectively maintained the boys' room-cleaning behavior and, during a fading condition where the percentage of days when the contingency occurred was decreased, the point consequences remained effective for over six months, even when they were delivered on only 8% of the days. Experiment III showed that the boys saved considerable amounts of money when point consequences were available for deposits but saved little money when no points were available. Also, when points were given only for deposits that occurred on specific days the boys deposited their money almost exclusively on those days. In Exp. IV, point consequences contingent on the number of correct answers on a news quiz produced the greatest increase in the percentage of boys who watched the news and, to a lesser extent, increased the percentage of correct answers for the boys who watched the news. The results indicate that "pre-delinquent" behaviors are amenable to modification procedures and that a token reinforcement system provides a practical means of modifying these behaviors.  相似文献   
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Experiments were conducted to establish training procedures and testing conditions that produce uniform and reliable swimming performance of rats in an automated swim alley. Data are given on the effect of water temperature and of platform rest interval on swimming speeds. In this system, rats will swim intermittently for as long as 24 h for a distance of more than 7 km.  相似文献   
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Block ( 2012 ) highlights two experimental studies of neglect patients which, he contends, provide ‘dramatic evidence’ for unconscious seeing. In Block's hands this is the highly non‐trivial thesis that seeing of the same fundamental kind as ordinary conscious seeing can occur outside of phenomenal consciousness. Block's case for it provides an excellent opportunity to consider a large body of research on clinical syndromes widely held to evidence unconscious perception. I begin by considering in detail the two studies of neglect to which Block appeals. I show why their interpretation as evidence of unconscious seeing faces a series of local difficulties. I then explain how, even bracketing these issues, a long‐standing but overlooked problem concerning our criterion for consciousness problematizes the appeal to both studies. I explain why this problem is especially pressing for Block given his view that phenomenal consciousness overflows access consciousness. I further show that it is epidemic—not only affecting all report‐based studies of unconscious seeing in neglect, but also analogous studies of the condition most often alleged to show unconscious seeing, namely blindsight.  相似文献   
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This research tested the use of concept map planning to support the development of creativity in photo stories, hypothesizing that skills taught to support organization would improve creativity. Concept maps are a type of graphic organizer, used to represent an ordering of ideas with nodes and linking words that form propositional statements. They were applied to story development under the assumption that the creative development of narrative elements requires organization. Undergraduate education students were randomly assigned to either concept map or text-based planning groups for the production of digital photo stories. Creativity was operationalized using dimensions of novelty, interest, clarity, and ability to be understood. A multivariate effect of planning method was found for these dimensions favoring the concept map group, due largely to greater clarity in the photo stories. Clarity in photo stories adds to their utility as creative products. This study represents first steps toward empirically assessing concept maps for a creative purpose, and further investigation, with a larger sample in an authentic context, over a longer period of planning time is recommended.  相似文献   
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