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71.
Experiment 1 showed that laboratory-reared desert kangaroo rats, like domestic Norway rats, efficiently search for food on a radial arm maze (RAM) by avoiding revisiting arms within a trial. By placing an RAM on the floor so the animals could approach food from any direction, Experiment 2 tested whether efficient search by kangaroo rats was based on tactics of distance minimizing, central-place foraging, trail following, or meandering. In contrast to the dominant trail-following tactic of domestic Norway rats (Hoffman, Timberlake, Leffel, & Gont, 1999), kangaroo rats tended to distance minimize, whether maze arms were present or not. Experiment 3 indicated that kangaroo rats treated a floor configuration of eight food cups as two patches of four, based on beeline travel between patches and meandering within them. We conclude that similar performance in an elevated RAM by different species can be based on different tactics, and we suggest that a laboratory apparatus can be used to cast light on niche-related mechanisms. 相似文献
72.
The purpose of this study was to explore potential differences between Asian and non-Asian university students in attitudes toward coercive and noncoercive sexual behavior. Four hundred women and men (205 Asian, 195 non-Asian) were assessed on attitudes towards rape, sexual harassment, and general sexual behavior. Length of residency in Canada for Asian respondents was examined to determine whether Westernization might attenuate differences. Analysis revealed that Asian students were significantly more conservative in attitudes toward sexual behavior. Asian students were also more tolerant of rape myths and more accepting of sexual harassment. Asian respondents demonstrated a decrease in tolerance for rape myths and sexual harassment as length of residency in Canada increased. Women were less conservative than men from the same background on almost all items. 相似文献
73.
A blind man (E.A.) was asked to draw pictures suggesting wheels in various kinds of motion. Six pictures were drawn by E.A. The pictures were shown to sighted subjects, who were asked to assign labels to the pictures, in a multiple-choice format. The labels were assigned at a rate above chance. We argue that the pictures are metaphoric and that pictorial metaphor relies on common properties of the static picture and the kinetic referent. 相似文献
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Shape-from-shadow perception fails when the contour bordering a shadowed area is reduced to a black line, and the shadow area becomes white. It might be that the polarity of the shadowed and illuminated areas has to be from dark on the shadowed side to light on the illuminated side for successful perception. Or it may be that the line, which has two contours, has one too many for shape-from-shadow processing. Alternatively, the problem might be that one of the contours of the line is incorrectly polarised. To test these explanations, three shape-from-shadow figures were prepared, each depicting the same referent--an elderly person. All three figures had two correctly polarised areas. One figure had a correctly polarised contour at the border between the areas. One had two correctly polarised contours. The other had one correctly polarised contour and one incorrectly polarised contour. The referent of the figure with one incorrectly polarised contour was the one difficult to make out. The result has implications for several theories, including an account of a demonstration by Hering involving penumbra. 相似文献
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Two notions strongly held by many smokers are that negative mood increases smoking behavior and that this increase is due to the ability of smoking to alleviate negative affect. This study used a modified mood induction procedure to examine both the impact of smoking on induced mood, as well as the effect of induced mood on actual smoking behavior. Forty-eight smokers were randomly assigned to a smoking or a water-drinking comparison group. Each participant attended 3 sessions during which 1 of 3 mood states (positive, negative, or neutral) was induced. Contrary to expectation, smoking did not attenuate negative affect. However, negative mood induction subsequently quickened latency to smoke and increased number of puffs consumed ad lib. 相似文献
78.
Suveg C Zeman J Flannery-Schroeder E Cassano M 《Journal of abnormal child psychology》2005,33(2):145-155
Compared emotion socialization in 26 children with anxiety disorders ages 8–12 years and their mothers to 26 nonclinical counterparts without psychopathology. Children and their mothers participated in an emotion interaction task in which they discussed occasions when the child felt worry, sadness, and anger. Responses were coded for length of discussion, proportion of words spoken by child vs. mother, frequency of positive and negative emotion words, explanatory discussion of emotion, and maternal facilitation of emotion discussion. Children and their mothers also completed the Expressiveness and Control scales of the Family Environment Scale. Results indicated that mothers of children with an anxiety disorder spoke less frequently than their child, used significantly fewer positive emotion words, and discouraged their childrens emotion discussions more than did mothers of nonclinical children. Nonclinical children and their mothers indicated significantly more emotional expressiveness in their families than did children with an anxiety disorder and their mothers. These results highlight the potential role of truncated family emotional expressivity in the emotional development and functioning of children with an anxiety disorder. 相似文献
79.
The Brief Fear of Negative Evaluation Scale (BFNE; M. R. Leary, 1983a) is often used to assess fear of negative evaluation, the core feature of social anxiety disorder. However, few studies have examined its psychometric properties in large samples of socially anxious patients. Although the BFNE yields a single total score, confirmatory factor analysis indicated a 2-factor solution to be more appropriate, with the 1st factor consisting of all straightforwardly worded items (BFNE-S) and the 2nd of all reverse-scored items (BFNE-R). Support was obtained for the convergent and discriminant validity of the BFNE and BFNE-S, but not the BFNE-R. These results suggest that standard scoring of the BFNE may not be optimal for patients with social anxiety disorder. 相似文献
80.
Developing human-nonhuman chimeras in human stem cell research: ethical issues and boundaries 总被引:1,自引:0,他引:1
The transplantation of adult human neural stem cells into prenatal non-humans offers an avenue for studying human neural cell development without direct use of human embryos. However, such experiments raise significant ethical concerns about mixing human and nonhuman materials in ways that could result in the development of human-nonhuman chimeras. This paper examines four arguments against such research, the moral taboo, species integrity, "unnaturalness," and human dignity arguments, and finds the last plausible. It argues that the transfer of human brain or retinal stem cells to nonhuman embryos would not result in the development of human-nonhuman chimeras that denigrate human dignity, provided such stem cells are dissociated. The article provides guidelines that set ethical boundaries for conducting such research that are consonant with the requirements of human dignity. 相似文献