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61.
In the behavior systems view, a long CS–US interval should differentially condition a general search mode and related behavior, while a short CS–US interval should differentially condition a focal search mode and related behavior. Two experiments paired a long or a short CS with food, and then, during an extinction test, compounded the CS with an unconditioned probe-stimulus of a rolling ball-bearing. Presuming that the long CS differentially conditions a general search mode, and that unconditioned contact of a moving stimulus is characteristic of that mode, presentation of the long CS should facilitate interaction with the ball-bearing. Similarly, presuming that a short CS differentially conditions a focal search mode, and that feeder-directed responses are characteristic of this mode, presentation of a short CS should facilitate nosing in the food-tray. Consistent with these predictions, ball-bearing contact increased in rats receiving the long CS, while nosing in the food-tray was higher with the short CS. 相似文献
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63.
Abstract— Regions of objects that are partially obscured at the current retinal image are often perceptually filled in by the visual system (Kanizsa, 1979). In some cases (modal completion), this causes the filled-in region to appear tinged with the color and brightness of unobscured parts of that object, but m other cases (amodal completion), it does not (Michotte & Burke, 1951). It has recently been argued that modal and amodal completion both arise in preattentive vision, and may operate equivalently at that level (Davis & Driver, 1994, He & Nakayama, 1992, Shipley & Kellman, 1992). In this article, we show that they have different effects on attentive vision, with attention tending to spread to (and from) modally completed regions and their visible inducers, but not to (or from) comparable amodally completed regions and their inducers. This finding is consistent with visual attention operating on surfaces (e g, He & Nakayama, 1995) in a viewer-centered representation of the scene, after the operation of filling-in processes. 相似文献
64.
Carol Ann Davis Michael P. Brady Richard Hamilton Mary A. McEvoy Robert E. Williams 《Journal of applied behavior analysis》1994,27(4):619-637
High-probability requests were used to increase social interactions in 3 young boys with severe disabilities who had been identified as severely socially withdrawn. A multiple baseline design across participants was used to evaluate the effects of high-probability request intervention on (a) social initiations, (b) social responses, (c) continued interactions, and (d) performance of high- and low-probability requests. The students were observed in a second setting to examine generalization effects across peers who did not participate in the training sequence and settings. The results demonstrated that the high-probability requests increased the students' responsiveness to low-probability requests to initiate social behavior. Increases were also found in (a) unprompted initiations and extended interactions to the training peers, (b) unprompted initiations and extended interactions to peers who were not involved in the training procedure, and (c) generalized unprompted initiations and interactions in a second nontraining setting. The students maintained increased levels of initiations and interactions after all prompts were removed from both the training and nontraining settings. 相似文献
65.
ABSTRACT This investigation used data from Loehlin and Nichols's (1976) study of over 800 sets of twins to examine evidence for the heritability of three facets of empathy: empathic concern, personal distress, and perspective taking. Expert judges first identified sets of adjectives, included within Loehlin and Nichols's original data, which reflected each empathy construct; these items were then validated in an independent sample. Comparisons of the responses given to these items by identical and fraternal twins in the Loehlin and Nichols investigation revealed evidence of significant heritability for characteristics associated with the two affective facets of empathy—empathic concern and personal distress—but not for the nonaffective construct of perspective taking. This pattern is consistent with the view that temperamental emotionality may underlie the heritability of affective empathy. 相似文献
66.
This paper explores the nature of thematic information made available when a verb is accessed during sentence comprehension. Following Shapiro, Zurif, and Grimshaw (1987), a cross-modal lexical decision (interference) task was employed to examine whether either the number of argument structures or the number of participant (thematic) roles inherent in a verb cause an increase in processing load upon access of the verb. It was determined that there was no evidence for such an increased processing load covarying with the number of argument structures of the verb, at least for those verb types examined in this study. However, there was an increase in processing load as a direct function of the number of participant roles carried by the verb. It is concluded that the participant roles (thematic roles associated with the central meaning of the verb) are stored with the representation of a verb and are made immediately, available upon access of the verb for further processing during comprehension.The first author gratefully acknowledges discussion and advice from Adele Goldberg and the support of grant T32 DC 00041 in pursuing this work. The second author acknowledges the support of NIH grant RO1 DC00494 for the work presented in this paper, and the helpful comments and criticisms of a reviewer. 相似文献
67.
This article focuses on the historical origin of the African-American male-female relationship dilemma and contemporary forces that have an impact on opportunities for intimacy and marriage among African-American women. Specifically, loss, communication, and stereotypes are examined as counseling issues that are relevant to African-American women in relationships. Implications for counseling and research are also discussed. 相似文献
68.
69.
With the end of the cold war, issues of environment and economic development are assuming greater international salience.
By the 1970s, environmental degradation was becoming pervasive, with growing global effects. Increasingly, global and emergent
globalized problems are forcing environmental interdependence on the world. Transboundary threats cannot be addressed unilaterally
by any single country or group of countries. The global environmental agenda is reviving the North-South debate and rejuvenating
the Third World coalition in international fora.
The encouragement of environmentally sustainable forms of industrialization in the South requires expanded and improved international
cooperation. However, the North’s greater resources and greater responsibility in causing global environmental degradation
require its continuing involvement in the search for solutions, including ones applicable to newly industrializing countries.
In June 1992, the largest intergovernmental conference ever held was convened in Rio de Janeiro to address these issues: the
United Nations Conference on Environment and Development (UNCED, or the Earth Summit). It produced a consensus action plan
of about 700 pages: Agenda 21. Agenda 21 presents massive challenges for international cooperation as well as for national
and private actors and scientific and technical institutions. It reflects a complex configuration of demands for institutional
arrangements that support environmentally sustainable technical and socioeconomic change. One of the most consistent of the
Agenda 21 themes, and one of the most intractable issues, concerns “access to technology.” This can be as straightforward
as diagnosing and improving the efficiency of a production process in a small manufacturing firm, or as complex as engineering
a technological revolution in which production and consumption take place with virtually no material or energy loss to the
environment. The selection of entry points for action is a critical strategic problem as well as an important operational
issue.
In this paper I identify and describe new initiatives intended to improve the environmental performance of industry in the
South, and find that they largely aim to promote incremental industrial innovation through international technology transfer
and diffusion. This strategy raises many questions about how to promote effective technology transfer and diffusion.
This is a revised version of a paper prepared for the ORSTOM/UNESCO Conference “20th Century Science: Beyond the Metropolis,”
Paris, 19–23 Sept. 1994. 相似文献
70.
Dena S Davis 《Kennedy Institute of Ethics journal》1995,5(4):343-354
The creation of embryos for research use has drawn a great deal of criticism. It is difficult to defend an ethical distinction between what one can do to "spare" embryos and what one can do to "research" embryos. The strongest ground on which to argue against the creation of embryos for research is a symbolic one, having to do with respect for human life. Ronald Dworkin's work in Life's Dominion on the symbolic meaning of the abortion debate throws a helpful light on this dispute. By understanding the basic question to be, Does the creation of research embryos weaken or insult our communal respect for the sanctity of human life in some way that in vitro fertilization (IVF) or the experimental use of "spare" embryos does not?, the debate can move in a more constructive direction. 相似文献