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241.
Past researches showed that empathy for pain not only triggers a resonance mechanism between other and self, but also is modulated by contextual factors. Using functional magnetic resonance imaging, the present study demonstrated that short-term media violence exposure reduced both pain ratings and also the activation of anterior insula and anterior mid-cingulate cortex to other’s pain. Thus, violence exposure modulated empathic responses to other’s pain based on a physiological desensitization.  相似文献   
242.
探讨并比较真实火灾和模拟火灾情境下小鼠是否采用直觉性逃生决策。研究包括一个预备训练和两个主实验。预备训练的目的:首先训练小鼠获得有关迷宫路线及出口的经验,然后再经过遗忘处理使它们遗忘相关经验。两个主实验均采用3(情境:真实火灾,模拟火灾,普通情境)×2(记忆:遗忘前和遗忘后)混合实验设计,因变量均为逃生决策。实验组被试为72只经过训练的小鼠,控制组为24只未经过训练的小鼠。通过考察小鼠在不同情境和不同记忆条件下的逃生时间和对逃生出口的选择探测并比较真实火灾和模拟火灾情境下小鼠的逃生决策差异。主要结果:(1)实验组在真实火灾情境下的逃生时间无论遗忘前后都明显比模拟火灾情境下短;(2)实验组在真实火灾和模拟火灾情境下的逃生时间都明显比控制组短;(3)当熟悉和陌生出口均开启同时熟悉出口处有烟雾条件下,真实火灾组在遗忘前后均倾向于选择熟悉出口逃生,其他两组则倾向于选择陌生出口离开。结论:真实火灾和模拟火灾情境下小鼠的逃生决策存在明显差异:真实火灾情境下受过训练的小鼠倾向于直觉性逃生决策;模拟火灾情境下受过训练的小鼠不倾向于直觉性逃生决策。  相似文献   
243.
ABSTRACT

The interaction between interfacial dislocations and γ/γ′ interface is critical to the high temperature creep properties of single crystal superalloys. However, only a few studies have paid attention to the detailed structure such as local interfacial morphologies and the elemental distribution around interfacial dislocations. In this paper, the interfacial protrusions and related dislocations in a single crystal superalloy after creep at high temperature – low stress have been investigated in detail. It is found that the morphology and size of the interfacial protrusions remain almost the same during the early and middle stages of high temperature creep, which indicates a local equilibrium at the interfacial protrusions. Steps at different height are formed at the γ/γ′ interface at the initial stage of high temperature creep since dislocations could move along the γ/γ′ interface, which indicates that dislocation motion at different creep stage may affect the morphology of γ/γ′ interface.  相似文献   
244.

The position of Dy in the unit cell of Bi2Sr2CaCu2Oy has been determined by a real-space method. This is compared with the reciprocal-space atom location by channelling-enhanced microanalysis (ALCHEMI) method.  相似文献   
245.

Contact problems between two solids are essential to interpret the loading-unloading behaviour in indentation tests. Using linear elastic theory, a general relationship between the normal stress and the surface deformation for elastic contact of two solids was derived, in which the normal stress is a function of the mean curvature of the undeformed surface.  相似文献   
246.
The current study tested 2 models of inhibition in 45 children with language impairment and 45 children with normally developing language; children were aged 7 to 12 years. Of interest was whether a model of inhibition as a mental-control process (i.e., executive function) or as a mental resource would more accurately reflect the relations among mental-attentional (M) capacity, inhibition, updating, shifting, and language competence. Children completed measures of M-capacity (in the verbal and nonverbal domains), inhibition, updating, shifting, and language. Path analyses showed the data provided a poor fit to the model of inhibition as a mental-control process but a good fit to the model of inhibition as a mental resource. Results are consistent with the theory of constructive operators and suggest inhibition is a mental resource rather than a mental-control process.  相似文献   
247.
This research examines the early emergence of source-monitoring abilities. Previous research has consistently demonstrated that children as young as 3 to 4 years of age do well on simple versions of action-based source-monitoring tasks. Research on even younger children, however, remains lacking. In this study we examined whether 2½-year-olds could accurately recall source on a simplified task. For the procedure, we used an action-based task in which children collaborate with an experimenter to build a model farm. During construction, the child and the experimenter took turns placing items on the farm. After construction, children were administered a source memory test in which they were asked to recall who had placed each item. To more closely examine factors that influence source accuracy in this young population, we included two conditions that varied in terms of contextual support. In the no-context-cues condition, in line with typical source-monitoring tasks, children were asked the source test question while items were presented individually and the farm was not in view. In the context-cues condition, the original spatial array of farm items was left intact to provide additional cues for children's source decisions. The main finding was that children in both conditions showed high levels of source accuracy at test indicating a surprisingly early age of emergence for this ability. Also, as predicted, children in the context-cues condition were the most accurate in attributing source.  相似文献   
248.
The aim of the present study was to investigate the time course of the positive advantage in the expression classification of faces by recording event-related potentials (ERPs). Although neutral faces were classified more quickly than either happy or sad faces, a significant positive classification advantage (PCA)—that is, faster classification for happy than for sad faces—was found. For ERP data, as compared with sad faces, happy faces elicited a smaller N170 and a larger posterior N2 component. The P3 was modulated by facial expressions with higher amplitudes and shorter latencies for both happy and neutral stimuli than for sad stimuli, and the reaction times were significantly correlated with the amplitude and latency of the P3. Overall, these data showed robust PCA in expression classification, starting when the stimulus has been recognized as a face revealed by the N170 component.  相似文献   
249.
Eye-tracking technique and visual search task were employed to examine the cognitive advantage for one’s own name and the possible effect of familiarity on this advantage. The results showed that fewer saccades and an earlier start time of first fixations on the target were associated with trials in which participants were asked to search for their own name, as compared to search for personally familiar or famous names. In addition, the results also demonstrated faster response times and higher accuracy in the former kind of trials. Taken together, these findings provide important evidence that one’s own name has the potential to capture attention and that familiarity cannot account for this advantage.  相似文献   
250.
Previous studies have shown that a plausible preview word can facilitate the processing of a target word as compared to an implausible preview word (a plausibility preview benefit effect) when reading Chinese (Yang, Wang, Tong, & Rayner, 2012; Yang, 2013). Regarding the nature of this effect, it is possible that readers processed the meaning of the plausible preview word and did not actually encode the target word (given that the parafoveal preview word lies close to the fovea). The current experiment examined this possibility with three conditions wherein readers received a preview of a target word that was either (1) identical to the target word (identical preview), (2) a plausible continuation of the pre-target text, but the post-target text in the sentence was incompatible with it (initially plausible preview), or (3) not a plausible continuation of the pre-target text, nor compatible with the post-target text (implausible preview). Gaze durations on target words were longer in the initially plausible condition than the identical condition. Overall, the results showed a typical preview benefit, but also implied that readers did not encode the initially plausible preview. Also, a plausibility preview benefit was replicated: gaze durations were longer with implausible previews than the initially plausible ones. Furthermore, late eye movement measures did not reveal differences between the initially plausible and the implausible preview conditions, which argues against the possibility of misreading the plausible preview word as the target word. In sum, these results suggest that a plausible preview word provides benefit in processing the target word as compared to an implausible preview word, and this benefit is only present in early but not late eye movement measures.  相似文献   
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