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281.
Four studies tested the application of to the drawing domain. In particular, we tested her claim that young children are inhibited in their attempts at changing their graphic representations (representational change) due to being constrained by the order in which the elements of the representation are drawn (procedural rigidity). The first study required 60 children (4- to 6-year-olds and an older comparison group of 8-year-olds) to make three drawings of a familiar and novel topic. From these drawings each child was measured for procedural rigidity. In a further drawing the child was asked to modify their usual representation of each topic. Regression analyses revealed procedural rigidity levels were not predictive of manipulation performance. A second study, testing 75 4- to 6-year-olds and a third study, testing 30 3- to 4-year-olds, revealed that when young children were specifically asked to manipulate rigid sub-procedures on a familiar topic they were indeed able to do so. Finally, a fourth study (testing 40 5-year-olds and 40 8-year-olds) removed the notational trace in drawing (a possible aid for procedural interruption) but this still produced no evidence of a relation between procedural rigidity and representational change. We suggest how the concept of procedural rigidity might be re-interpreted for the drawing domain so that the RR model can remain as a domain-general theory of cognitive development. We also suggest the development of information processing may be crucial for flexibility in drawing.  相似文献   
282.
Let each of several (generally interdependent) random vectors, taken separately, be influenced by a particular set of external factors. Under what kind of the joint dependence of these vectors on the union of these factor sets can one say that each vector is selectively influenced by “its own” factor set? The answer proposed and elaborated in this paper is: One can say this if and only if one can find a factor-independent random vector given whose value the vectors in question are conditionally independent, with their conditional distributions selectively influenced by the corresponding factor sets. Equivalently, the random vectors should be representable as deterministic functions of “their” factor sets and of some mutually independent and factor-independent random variables, some of which may be shared by several of the functions.  相似文献   
283.
Across many languages, speakers tend to produce sentences so that given (previously referred to) arguments are mentioned before new arguments; this is termed given-new ordering. We explored the nature of such given-new effects in Japanese using a procedure following Bock and Irwin (1980). Speakers encoded and then recalled canonical (e.g., okusan-ga otetsudaisan-ni purezento-o okutta, the housewife gave the housekeeper a present) or scrambled (okusan-ga purezento-o otetsudaisan-ni okutta) dative targets when prompted by a statement-question sequence. The prompting statement established one nonsubject argument of the dative target as given, leaving the other nonsubject argument as new. Previous mention was either with lexically identical content (e.g., otetsudaisan or purezento) or with lexically distinct but nearly synonymous content (meidosan, housemaid or okurimono, gift). Results showed that speakers produced canonical or scrambled word orders so that given arguments were mentioned before new, but especially when the previous mention of the given argument occurred with lexically identical content (replicating Bock and Irwin's English effect). These results show that the production of Japanese scrambled and canonical word orders is sensitive to given versus new status (as in English), implying that given-new ordering arises at the stage of sentence production where scrambling effects are realized.  相似文献   
284.
This investigation compared the predictions of two models describing the integration of reinforcement and punishment effects in operant choice. Deluty's (1976) competitive-suppression model (conceptually related to two-factor punishment theories) and de Villiers' (1980) direct-suppression model (conceptually related to one-factor punishment theories) have been tested previously in nonhumans but not at the individual level in humans. Mouse clicking by college students was maintained in a two-alternative concurrent schedule of variable-interval money reinforcement. Punishment consisted of variable-interval money losses. Experiment 1 verified that money loss was an effective punisher in this context. Experiment 2 consisted of qualitative model comparisons similar to those used in previous studies involving nonhumans. Following a no-punishment baseline, punishment was superimposed upon both response alternatives. Under schedule values for which the direct-suppression model, but not the competitive-suppression model, predicted distinct shifts from baseline performance, or vice versa, 12 of 14 individual-subject functions, generated by 7 subjects, supported the direct-suppression model. When the punishment models were converted to the form of the generalized matching law, least-squares linear regression fits for a direct-suppression model were superior to those of a competitive-suppression model for 6 of 7 subjects. In Experiment 3, a more thorough quantitative test of the modified models, fits for a direct-suppression model were superior in 11 of 13 cases. These results correspond well to those of investigations conducted with nonhumans and provide the first individual-subject evidence that a direct-suppression model, evaluated both qualitatively and quantitatively, describes human punishment better than a competitive-suppression model. We discuss implications for developing better punishment models and future investigations of punishment in human choice.  相似文献   
285.
Competing theories regarding the effects of delivering periodic response-independent reinforcement (more accurately, response-independent points exchanged for money) on a baseline rate of behavior were evaluated in human subjects. Contiguity theory holds that these events decrease target responding because incompatible behavior is adventitiously strengthened when the point deliveries follow target behavior closely in time. Matching theory holds that response-independent points, like any other alternative reinforcer, should reduce target responding. On this view, temporal contiguity between target responding and response-independent point delivery is unimportant. In our experiment, four different responses (moving a joystick in four different directions) were reinforced with points exchangeable for money according to four independent variable-interval schedules. Different schedules of point delivery were then superimposed on these baselines. When all superimposed point deliveries occurred immediately after one of the four responses (the target response), time allocated to target responding increased. When the superimposed point deliveries could be delivered at any time, time allocated to target responding declined and other behavior increased. When superimposed points could never immediately follow target responses, time allocated to target responding decreased further and other behavior or pausing predominated. The findings underscore the contribution of temporal contiguity in the effects of response-independent deliveries of food, money, points, etc.  相似文献   
286.
Levy J  Yovel G  Bean M 《Brain and language》2003,87(3):432-440
The influence of lateralized unattended stimuli on the processing of attended stimuli in the opposite visual field can shed light on the nature of information that is transferred between hemispheres. On a cued bilateral task, participants tried to identify a syllable in the attended visual field, which elicits a left hemisphere (LH) advantage and different processing strategies by the two hemispheres. The same or a different syllable or a neutral stimulus appeared in the unattended field. Transmission of unattended syllable codes between hemispheres is symmetric, as revealed by equal interference for the two visual fields. The LH is more accurate than the RH in encoding unattended syllables, as indicated by facilitation in the left but not right visual field and a greater frequency of identifiable intrusions into the left than right field. However, asymmetric encoding strategies are different for attended and unattended syllables.  相似文献   
287.
Does age constrain the outcome of all language acquisition equally regardless of whether the language is a first or second one? To test this hypothesis, the English grammatical abilities of deaf and hearing adults who either did or did not have linguistic experience (spoken or signed) during early childhood were investigated with two tasks, timed grammatical judgement and untimed sentence to picture matching. Findings showed that adults who acquired a language in early life performed at near-native levels on a second language regardless of whether they were hearing or deaf or whether the early language was spoken or signed. By contrast, deaf adults who experienced little or no accessible language in early life performed poorly. These results indicate that the onset of language acquisition in early human development dramatically alters the capacity to learn language throughout life, independent of the sensory-motor form of the early experience.  相似文献   
288.
支撑—活动观、社会共享认知观以及实践共同体观是当前情境理论中具有代表性的迁移观点。这些观点分别从不同的角度强调情境特性对迁移的影响,并主张在常规的学校教育中突出情境、尤其是社会文化与社会实践情境的作用。  相似文献   
289.
陆九渊以心解《易》,以此为其心学理论体系的建立和展开寻找到经典根据。其心学的本体论、工夫论和境界论与其对《周易》天地人三才一体的理论、三陈九卦之序、《艮》卦"艮背行庭"之旨、太极本体的解释关系密切。他的心学智慧也反过来丰富了《易》学的文化宝藏。  相似文献   
290.
This paper informally summarizes a two-day symposium held at the U.S. National Academy of Sciences in Washington, D.C., September 5–6, 2002. The issue was to what extent the progress of science and societal capacity for continued technological innovation are threatened by excessive protection of intellectual property. Excessive protection creates disadvantages not only for scientists and inventors but also for educators/students and for librarians/clientele. Speakers from a variety of disciplines and institutions agreed unanimously that scientific and technological progress is, indeed, under serious threat. Various opinions were expressed about the degree of threat, currently and prospectively, as well as what counter-measures are best suited to resist undue restrictions on creative uses of scientific and technical data and information. This summary is based entirely on the author’s notes from the symposium, and the commentary offered is his alone. My apologies to the speakers if this paper does not accurately reflect the primary intent of their presentations. The “Suggested Readings” offered at the end are not specific to the speakers’ statements but rather are offered as a general resource to aid further research. The definitive record of the symposium is planned to be available from the National Academies Press as a Proceedings publication in the summer of 2003. John Gardenier is an independent researcher, ethicist and science writer.  相似文献   
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