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211.
Effects of luminance and contrast on direction of ambiguous apparent motion   总被引:1,自引:0,他引:1  
S M Anstis  G Mather 《Perception》1985,14(2):167-179
A study is reported of the role of luminance and contrast in resolving ambiguous apparent motion (AM). Different results were obtained for the short-range (SR) and the long-range (LR) motion-detecting processes. For short-range jumps (7.5 min arc), the direction of ambiguous AM depended on brightness polarity, with AM only from white to white and from black to black. But for larger jumps, or when an interstimulus interval (ISI) was introduced, AM was less dependent on polarity, with white often jumping to black and black jumping to white. Two potential AMs were pitted against each other, one carried by a light stimulus and the other by a dark stimulus. The stimulus whose luminance differed most from the uniform surround captured the AM. Visual response to luminance was linear, not logarithmic. When the stimulus was modified to give continuous AM in one direction it was followed by a negative aftereffect of motion only when the spatial displacement was 1 min arc. A larger displacement (10 min arc) gave good AM but no motion aftereffect. Thus only short-range motion adapts motion-sensitive channels.  相似文献   
212.
This study describes the development of the Attitudes Toward Women Scale for Adolescents (AWSA), an instrument based on the short form of the Spence-Helmreich Attitudes Toward Women Scale (AWS). The AWSA has been tested in four samples of adolescents. Internal consistency estimates and test-retest stability indicated high reliability. Hypotheses formulated to test the construct validity of the scale were largely supported. AWSA permits the examination of how boys' and girls' attitudes toward women influence the life paths that adolescent girls begin to pursue.This research was supported by grants to A. Petersen from the Spencer Foundation, the National Institute of Mental health (MH 30252/38142), and the Judith Baskin Offer Fund.  相似文献   
213.
The present study examined the effects of competitive outcome—either a win or a loss—on intrinsic motivation. Winning was hypothesized to facilitate both performance and intrinsic motivation. Fifty-four participants, 29 females and 25 males, competed against a same-gender confederate in a puzzle-solving contest. Following the competition, participants' intrinsic motivation was surreptitiously measured by the amount of time spent playing with the puzzle while alone. Results showed that winning facilitated both actual competitive performance and intrinsic motivation relative to losing. The importance of considering the outcome when predicting intrinsic motivation after competition is discussed.  相似文献   
214.
This essay provides guidelines for designing a doctoral program in behavior analysis. First, we propose a general accomplishment for all behavior analytic doctoral students: that they be able to solve problems concerning individual behavior within a range of environments. Second, in order to achieve this goal, we propose that students be trained in conceptual and experimental analysis of behavior, the application of behavioral principles and the administration of behavioral programs. This training should include class work, but it should emphasize the immersion of students in a variety of environments in which they are required to use behavior analytic strategies. Third, we provide an example of a hypothetical graduate program that involves the proposed training. Finally, an evaluation plan is suggested for determining whether a training program is in fact producing students who are generalized problem-solvers. At each step, we justify our point of view from a perspective that combines principles from behavior analysis and educational systems design.  相似文献   
215.
216.
Sternheim and Boynton’s (1966) continuous judgmental color-naming technique was used to assess the elemental nature of achromatic colors. Results from three subjects indicate that the names “black” and “white” are necessary and sufficient to describe achromatic test lights associated with the name “gray.” On the basis of the criteria that establishes a color as elemental, black and white were confirmed as elemental, whereas gray was not. These findings support the assumption of various opponent processing models that there are only two elemental achromatic sensations. In addition, the results support Hering’s (1920) view that black and white differ from the paired-chromatic opponent colors in that they are not mutually exclusive.  相似文献   
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218.
This experiment compared the effects of high-level and low-level postpassage questions, when presented immediately after the passage segment containing the answer to the question, on college students' free recall of expository prose passages. Low-vocabulary subjects' recall of high-level information not specifically quizzed by the postpassage questions was significantly greater in the condition in which the questions quizzed a high-level unit than in the low-question and no-question conditions, p less than .05. These results are interpreted as being consistent with a direct-access explanation which assumes that questions presented in close temporal contiguity to the quizzed information directly access that information in memory and that fewer associative links have to be traversed in the spread of activation from high-level units to other related information in the hierarchy. The effect of type of question in this experiment was compared with that found in an earlier experiment (Wilhite, 1982) involving delayed question presentation.  相似文献   
219.
Dieting and binging. A causal analysis   总被引:16,自引:0,他引:16  
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220.
We have become a drug-oriented society. Cummings (1979), citing evidence from the National Institute of Drug Abuse, reports that one of every eleven adult Americans suffers from a severe addictive problem. Drug addition is epidemic among teenagers; one of every six teenagers suffers from a severe addictive problem. This paper focuses on adolescent drug/substance abuse.  相似文献   
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