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241.
Felisa González David García-Burgos Isabel de Brugada Marta Gil 《Learning and motivation》2010,41(2):141-149
In two experiments, thirsty rats consumed a compound of sucrose and a non-preferred flavor. In Experiment 1, a conditioned preference was observed in the experimental group when animals were tested both thirsty and hungry, but not when they were tested just thirsty. Animals in the control group, which experienced the flavor and the sucrose unpaired, never showed a preference. Experiment 2 replicated the absence of a preference in the experimental group when rats were tested thirsty, but provided evidence that a flavor-taste association had been formed during training. After conditioning, sucrose was paired with LiCl in group Dev whereas it was unpaired in group NonDev. The sucrose devaluation produced a decrease in CS preference in group Dev, and an increment in group NonDev. Taken together, these results show that preference for a non-preferred flavor can be readily observed after pairings with the positive consequences of the US (calories or absence of an expected illness) rather than with a palatable flavor. 相似文献
242.
Weidong Cao 《Frontiers of Philosophy in China》2006,1(1):41-50
The main purpose of this essay is not to give a full-scale and systematic exploration of the historical process concerning
the acceptance of Habermas’ works in the Chinese-spoken world but to examine the historical effect of Habermas in the Chinese-spoken
context and try to find a proper way to establish a good relationship between Habermas and the Chinese-spoken world by discussing
the introduction, study, and application of Habermas’ most famous work, The Structural Transformation of the Public Sphere, by Chinese scholars in recent years.
Translated from Xiandai zhexue, 2005:1 相似文献
243.
244.
“多少”概念发展的研究 总被引:1,自引:0,他引:1
采用数量判定任务,分别用2~30和5~100范围内点子图为刺激,研究个体“多”和“少”概念的发展。结果发现:在5~100点子条件下,随年龄的增长,个体“多”概念的判断值、“少”概念的判断值、“多”“少”概念的临界值均显著增大;7~9岁是个体“多少”概念发展的转折期;个体对“多少”概念的认知具有相对性;在本实验的两种条件下,随年龄增长,个体“多”概念的判断值、“少”概念的判断值、“多”“少”概念的临界值逐渐趋于刺激点子数最大值的2/3、1/3、1/2,“多”概念与“少”概念判断的不确定距离逐渐趋于刺激点子数最大变化范围的1/3或略小于1/3。 相似文献
245.
Antoine Jérusalem 《Philosophical Magazine Letters》2013,93(9):599-609
Owing to their very high strength, nanocrystalline metals have been extensively studied over the recent years. The direct Hall–Petch law, empirically proportioning the material strength to the inverse square root of its grain size has been shown to break down below a grain size of the order of tenths of nanometers. This phenomenon has been widely rationalized as a gradual switch from intragrain mediated deformation mechanisms to grain boundary mediated deformation mechanisms. This transition has been observed in many finite element simulations, despite the intrinsic restriction of necessarily limiting the nanocrystalline representative assembly to only a few grains. Such a limitation is generally overlooked, and its influence on an uniaxial tension test – when compared to a complete sample of millions of grains – ignored. We propose here to quantify the approximation done by considering a finite number of grains by means of a simple analytical model based on the early work of Stevens [R.N. Stevens, Philos. Mag. 23 (1971) p. 265]. The finite element approximation is demonstrated to be relatively good, even down to only three grains in width, and a method to “correct” the stress-strain curves of small representative volumes is proposed. 相似文献
246.
The mechanical softening behaviour of micrometre-scale metals (free-standing metal foils and wires) with decreasing either the geometrical or the microstructural scale (i.e. the smaller, the weaker) has recently been reported. Here, we present a mechanism-based model to understand the softening behaviour, which is based on competition between the effects of surface grain relaxation and the interior grain strengthening effect. The model describes well the yield stress of Cu foils with different ratios of the thickness to grain size. 相似文献
247.
ABSTRACTThe effect of Retrieval Practice refers to the phenomenon that taking a practice test is more effective for learning than re-study, probably due to the benefit from processes underlying successful retrievals during practice. However, it is rarely studied whether other processes (e.g., metacognitive monitoring) during retrieval practice may also play an important role. In two experiments, we examined whether the effectiveness of retrieval was affected by subjects’ confidence in their retrieval success. Subjects studied word-pairs and rated their confidence after each practice test trial (cued-recall in Exp.1, multiple choice in Exp.2), or re-study trial. In both experiments, we observed the classic retrieval practice effect. Moreover, in Exp.2, the benefits differed as a function of subjects’ confidence in their retrieval performance: the effect of retrieval practice only emerged for high-confidence trials with higher than 56% confidence. In summary, the retrieval practice only facilitates the retention of correct answers with high confidence. 相似文献
248.
ABSTRACTAlthough previous research on retrieval practice (RP) has predominantly featured stimuli with discrete right-or-wrong answers, continuous measures offer potentially greater sensitivity in assessing the effects of RP on memory precision. The present study used a colour gradient (125 points ranging from magenta to yellow) as a continuous response variable. The colours of different images were learned through either RP or restudy and either one or three cycles of practice after initial study. On a delayed final test, participants’ memory was assessed for each item’s colour. Participants also created per-item intervals representing the region where they believed the correct colour most likely to have been. We found that repeated rounds of RP enhanced the correspondence between responses and the correct colour. In addition, RP led to participants creating more accurate (correct answers were more likely to be within the participant-specified intervals) and more precise (narrower) intervals relative to restudy, suggesting that RP enhances the precision of memories. 相似文献
249.
250.
Timothy D. Ritchie John J. Skowronski W. Richard Walker Sarah E. Wood 《Memory (Hove, England)》2013,21(4):471-485
Four samples of participants recalled autobiographical memories. While some evidence emerged from regression analyses suggesting that judgements of the amount of detail contained in each memory and judgements of the ease with which events could be recalled were partially independent, the analyses generally showed that these judgements were similarly predicted by various event characteristics (age, typicality, self-importance, emotional intensity at event occurrence, rehearsal types). Co-occurrence frequency data yielded similar conclusions, showing that while ease ratings and detail ratings occasionally diverged, they were more often consistent with each other. Finally, the data also suggested that events that prompted emotional ambivalence were not judged to be more easily recalled, or to contain more detail, than non-ambivalent events. 相似文献