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161.
Koronczai B Urbán R Kökönyei G Paksi B Papp K Kun B Arnold P Kállai J Demetrovics Z 《Cyberpsychology, behavior and social networking》2011,14(11):657-664
As the Internet became widely used, problems associated with its excessive use became increasingly apparent. Although for the assessment of these problems several models and related questionnaires have been elaborated, there has been little effort made to confirm them. The aim of the present study was to test the three-factor model of the previously created Problematic Internet Use Questionnaire (PIUQ) by data collection methods formerly not applied (off-line group and face-to-face settings), on the one hand, and by testing on different age groups (adolescent and adult representative samples), on the other hand. Data were collected from 438 high-school students (44.5 percent boys; mean age: 16.0 years; standard deviation=0.7 years) and also from 963 adults (49.9 percent males; mean age: 33.6 years; standard deviation=11.8 years). We applied confirmatory factor analysis to confirm the measurement model of problematic Internet use. The results of the analyses carried out inevitably support the original three-factor model over the possible one-factor solution. Using latent profile analysis, we identified 11 percent of adults and 18 percent of adolescent users characterized by problematic use. Based on exploratory factor analysis, we also suggest a short form of the PIUQ consisting of nine items. Both the original 18-item version of PIUQ and its short 9-item form have satisfactory reliability and validity characteristics, and thus, they are suitable for the assessment of problematic Internet use in future studies. 相似文献
162.
Valladolid-Acebes I Stucchi P Cano V Fernández-Alfonso MS Merino B Gil-Ortega M Fole A Morales L Ruiz-Gayo M Del Olmo N 《Neurobiology of learning and memory》2011,95(1):80-85
It has been suggested that hyperglycemia and insulin resistance triggered by energy-dense diets can account for hippocampal damage and deficits of cognitive behaviour. We wonder if the impairment of learning and memory processes detected in diet-induced obese (DIO) mice is linked to diet composition itself. With this purpose we have evaluated learning performance in mice undergoing a short-term high-fat (HF) treatment, which leads to a pre-obese state characterized by increased adiposity without significant changes of glucose and insulin plasma levels. C57BL/6J mice were fed either a HF (45 kcal% from fat) or control diet (10 kcal% from fat) during 8 weeks. Learning performance was evaluated by using the four-arm baited version of the eight-arm radial maze test (RAM). Mice were trained to learn the RAM protocol and then memory was tested at different time-points. Time spent to consume food placed in baited arms and errors committed to find them were measured in all sessions. DIO mice significantly spent more time in learning the task and made a greater number of errors than controls. Moreover, retention tests revealed that both working and total memory errors were also more numerous in DIO mice. The current results show that short-term DIO impairs spatial learning and suggest that impairment of hippocampal learning elicited by HF diets might be perceptible before metabolic alterations linked to obesity develop. 相似文献
163.
164.
González Sánchez L Rodríguez Pérez C Gázquez Linares JJ González Castro P Alvarez García D 《Psicothema》2011,23(2):239-244
We present a study that investigates changes in the acquisition and development of morphological awareness in children from 5 to 7 years old. This investigation was carried out on three separate occasions over two academic years, in which morphological awareness was assessed according to two levels. The data indicate an increase in the morphological awareness development from the kindergarten to primary education, verifying the acquisition in the first instance of the morphological judgment level and secondly, of morphological production level. It also generates a pattern of acquisition of the various parameters that make up morphology. 相似文献
165.
166.
This work extend to residuated lattices the results of [7]. It also provides a possible generalization to this context of frontal operators in the sense of [9]. Let L be a residuated lattice, and f : L k ?? L a function. We give a necessary and sufficient condition for f to be compatible with respect to every congruence on L. We use this characterization of compatible functions in order to prove that the variety of residuated lattices is locally affine complete. We study some compatible functions on residuated lattices which are a generalization of frontal operators. We also give conditions for two operations P(x, y) and Q(x, y) on a residuated lattice L which imply that the function ${x \mapsto min\{y \in L : P(x, y) \leq Q(x, y)\}}$ when defined, is equational and compatible. Finally we discuss the affine completeness of residuated lattices equipped with some additional operators. 相似文献
167.
Ágnes Melinda Kovács 《Developmental science》2009,12(1):48-54
In their first years, children's understanding of mental states seems to improve dramatically, but the mechanisms underlying these changes are still unclear. Such ‘theory of mind’ (ToM) abilities may arise during development, or have an innate basis, developmental changes reflecting limitations of other abilities involved in ToM tasks (e.g. inhibition). Special circumstances such as early bilingualism may enhance ToM development or other capacities required by ToM tasks. Here we compare 3‐year‐old bilinguals and monolinguals on a standard ToM task, a modified ToM task and a control task involving physical reasoning. The modified ToM task mimicked a language‐switch situation that bilinguals often encounter and that could influence their ToM abilities. If such experience contributes to an early consolidation of ToM in bilinguals, they should be selectively enhanced in the modified task. In contrast, if bilinguals have an advantage due to better executive inhibitory abilities involved in ToM tasks, they should outperform monolinguals on both ToM tasks, inhibitory demands being similar. Bilingual children showed an advantage on the two ToM tasks but not on the control task. The precocious success of bilinguals may be associated with their well‐developed control functions formed during monitoring and selecting languages. 相似文献
168.
ABSTRACT— This research examined whether describing past actions as ongoing using the imperfective aspect (rather than describing them as completed using the perfective aspect) promotes memory for action-relevant knowledge and reenactment of these actions in a future context. In Experiment 1 , participants who used the imperfective aspect to describe their strategy on a prior interpersonal task were more likely to use this strategy on a later task than were participants who used the perfective aspect to describe their prior strategy. Experiment 2 demonstrated that describing behaviors on a task using the imperfective rather than the perfective aspect increased willingness to resume that task by improving memory for task contents. The last two experiments showed that the effects of the imperfective aspect on memory decayed over time and that the imperfective aspect facilitated performance of a future behavior only when the described past behavior was relevant to the future behavior. Thus, the effects of aspect are moderated by memory decay and are behavior-specific. 相似文献
169.
This article compiles the investigations carried out by a Research Group of the University of Granada, Spain. Its different
projects on writing’s cognitive social and cultural processes have been supported by the Spanish Government. This line of
research joined together linguistic, psychological, social and cultural contributions to the development of writing from the
1970s. Currently, this line of research develops in collaboration with other European Universities: (a) Interuniversity Centre
for Research On Cognitive Processing in Natural and Artificial Systems (ECONA), “La Sapienza” University of Rome (Italy);
(b) Anadolu University, (Eskisehir, Turkey); (c) Coimbra University (Portugal); (d) University of Zaragoza (Spain); (e) the
Institute of Education of the University of London (United Kingdom). The aforementioned collaboration is materializing into
projects like the International Master on Multilingual Writing: Cognitive, Intercultural and Technological Processes of Written
Communication () and the International Congress: Writing in the twenty-first Century: Cognition, Multilinguisim and Technologies, held in
Granada (). This research line is focussed on the development of strategies in writing development, basic to train twenty-first century
societies’ citizens. In these societies, participation in production media, social exchange and the development of multilingual
written communication skills through new computer technologies spread multicultural values. In order to fulfil the social
exigencies, it is needed to have the collaboration of research groups for designing and applying international research projects.
International Master. Multilingual Writing Web: , . 相似文献
170.
People often face preferential decisions under risk. To further our understanding of the cognitive processes underlying these preferential choices, two prominent cognitive models, decision field theory (DFT; Busemeyer & Townsend, 1993 ) and the proportional difference model (PD; González-Vallejo, 2002 ), were rigorously tested against each other. In two consecutive experiments, the participants repeatedly had to choose between monetary gambles. The first experiment provided the reference to estimate the models' free parameters. From these estimations, new gamble pairs were generated for the second experiment such that the two models made maximally divergent predictions. In the first experiment, both models explained the data equally well. However, in the second generalization experiment, the participants' choices were much closer to the predictions of DFT. The results indicate that the stochastic process assumed by DFT, in which evidence in favor of or against each option accumulates over time, described people's choice behavior better than the trade-offs between proportional differences assumed by PD. 相似文献