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91.
Recently, several studies reported a relationship between immune system activation and anger expression. Consequently, the aim of this study was to explore immunitary molecular mechanisms that potentially underlie anger expression. To this end, we applied the Frustration—Aggression Theory in a contact sport model, utilizing the nearing of sporting events to trigger anger feelings. In parallel, we evaluated the activation of immune system at mRNA levels. We enrolled 20 amateur rugby players (age ± SD, 27.2 ± 4.5) who underwent psychological assessment to evaluate anger, with the State‐Trait Anger Expression Inventory‐2 (STAXI‐2), before rugby matches; at the same time blood samples were taken to analyze the variations of gene expression by microarray. During the 2 hr before each game, a significant increase was verified in the Rage State (RS) score compared to the score ascertained 72 hr before. At the same time, we found modulation in expression profile, in particular increased expression of gene that encodes interleukin l‐β (IL‐1β). In a regression analysis, RS score was related to IL‐1β, and the potential risk factors age, body mass index, smoking, and drinking. The levels of cytokine were positively and independently related to RS score. Our results suggest that the nearing of sporting event can trigger anger state feelings and activate immune system in rugby players. We propose the IL‐1β as a potential biological marker of anger. However, further research is necessary to clarify the correlation between cytokine and anger. Aggr. Behav. 39 :141‐148, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
92.
In this study we explored the temporal origin of processing differences between first and second language production. Forty highly proficient bilinguals named objects of high and low lexical frequency aloud for both L1 and L2 separately while event-related brain potentials (ERPs) were recorded. The first electrophysiological differences elicited by response language occurred at the same early P2 peak (∼140–220 ms) where we observed the onset of the lexical frequency effect, but only for those bilinguals who started naming in an L1 context and afterwards switched to an L2 naming context. The bilinguals who named objects in the reverse direction did not display a language effect in the ERPs. Taken together, the data show that the L2 naming disadvantage originates during the onset of lexical access and seems to be driven by both representational strength, which is lower for L2 words, and language control demands, which are higher for L2 words.  相似文献   
93.
In two experiments, 18-month-old infants’ categorization of 3D replicas and 2D photographs of the same animals and vehicles were compared to explore infants’ flexibility in categorization across different object representations. Using a sequential touching procedure, infants completed one superordinate and two basic-level categorization tasks with 3D replicas, 2D cut out photographs, or 2D images on photo cubes (“2D cubes”). For superordinate sets, 3D replicas elicited longer mean run lengths than 2D cut outs, and 3D replicas elicited equivalent mean run lengths as 2D cubes. For basic-level sets, infants categorized high-contrast animal sets when presented with 3D replicas, but they failed to categorize any of the 2D photograph sets. Categorization processes appear to differ for 3D and 2D stimuli, and infants’ discovery of object properties over time while manipulating objects may facilitate categorization, as least at the superordinate level. These findings are discussed in the context of infants’ representation abilities and the integration of perception and action.  相似文献   
94.
The canonical AX-CPT task measures two forms of cognitive control: sustained goal-oriented control (“proactive” control) and transient changes in cognitive control following unexpected events (“reactive” control). We modified this task by adding negative and neutral International Affective Picture System (IAPS) pictures to assess the effects of negative emotion on these two forms of cognitive control. Proactive and reactive control styles were assessed based on measures of behavior and electrophysiology, including the N2 event-related potential component and source space activation (Low Resolution Tomography [LORETA]). We found slower reaction-times and greater DLPFC activation for negative relative to neutral stimuli. Additionally, we found that a proactive style of responding was related to less prefrontal activation (interpreted to reflect increased efficiency of processing) during actively maintained previously cued information and that a reactive style of responding was related to less prefrontal activation (interpreted to reflect increased efficiency of processing) during just-in-time environmentally triggered information. This pattern of results was evident in relatively neutral contexts, but in the face of negative emotion, these associations were not found, suggesting potential response style-by-emotion interaction effects on prefrontal neural activation.  相似文献   
95.
高特质焦虑个体常表现出对威胁性刺激的选择性注意偏向的特点。然而其潜在的神经机制目前仍不清楚。通过记录高、低特质焦虑者各17名进行情绪加工时的ERP,比较了两组个体在选择性注意偏向发生的时间进程和相关的神经反应的差异。结果发现,高特质焦虑者诱发出更大的N1,进一步发现恐惧图片比中性图片诱发更大的N1;而低特质焦虑者诱发了更大的N2,特质焦虑得分越低, N2波幅越大。结果初步说明高特质焦虑者加工早期对恐惧图片分配了较多的注意资源,并且其抑制执行功能可能受损;而低特质焦虑者较晚开始区分恐惧图片和中性图片。这些结果提供了支持认知-动机模型的新证据。  相似文献   
96.
In this study, (Gd1? x Nd x )2(Zr1? x Ce x )2O7 (0 ≤ x ≤ 0.5) ceramics have been prepared by pressureless sintering at 1973 K to investigate the influence of Nd and Ce co-doping on their electrical conductivity. The electrical conductivity of the ceramics was investigated by impedance spectroscopy measurements from 723 to 1173 K over the frequency range of 20 Hz to 2 MHz in air. The measured values obey the Arrhenius relation. For each composition, the grain conductivity gradually increases with increasing temperature from 723 to 1173 K. At a given temperature, it gradually decreases with increasing neodymium and cerium contents from x = 0 to 0.3; thereafter, the grain conductivity exhibits a slight increase with further increasing neodymium and cerium contents up to x = 0.5.  相似文献   
97.
ABSTRACT

Recently a novel type of epithelial cell has been discovered and dubbed the ‘scutoid’. It is induced by curvature of the bounding surfaces. We show by simulations and experiments that such cells are to be found in a dry foam subjected to this boundary condition.  相似文献   
98.

The thermal stability of highly disordered mechanically alloyed nanocrystalline NiAl has been evaluated. The reordering of disordered NiAl(Cr) shows extremely fast kinetics on isothermal annealing at and above 673K, while the process is quite sluggish below this temperature. On the other hand, significant reordering in NiAl(Fe) takes place even at 573K. A unique dependence of reordering on the grain growth of the nanophase is evident during thermal treatment. Rapid grain coarsening begins only as the absolute temperature approaches approximately 0.4 T m, where T m is the melting point of the aluminide.  相似文献   
99.
When people think about how a situation might have turned out differently, they tend to imagine counterfactual alternatives to their actions. We report the results of three experiments which show that people imagine alternatives to actions differently when they know about a reason for the action. The first experiment (n = 36) compared reason – action sequences to cause – effect sequences. It showed that people do not imagine alternatives to reasons in the way they imagine alternatives to causes: they imagine an alternative to an action more than an effect, and to a cause more than a reason. The second experiment (n = 214) and the third experiment (n = 190) both show that different sorts of reasons have different sorts of effects on how people imagine alternatives to actions. People imagine an alternative to an action (the protagonist went to a ball) less often when they know the reason for the action was an obligation (he had to participate in fundraising) compared to when they know about a weaker reason (he wanted to meet a famous violinist) or no reason. The second experiment shows the effect for a social obligation and the third experiment replicates and extends it to a health obligation. We interpret the results in terms of the possibilities that people keep in mind about actions and their reasons.  相似文献   
100.
Wason's standard 2-4-6 task requires discovery of a single rule and leads to around 20% solutions, whereas the dual goal (DG) version requires discovery of two rules and elevates solutions to over 60%. We report an experiment that aimed to discriminate between competing accounts of DG facilitation by manipulating the degree of complementarity between the to-be-discovered rules. Results indicated that perfect rule complementarity is not essential for task success, thereby undermining a key tenet of the goal complementarity account of DG facilitation. The triple heterogeneity account received a good degree of support since more varied triple exploration was associated with facilitatory DG conditions, in line with this account's prediction that task success is associated with the creative search of the problem space. The contrast class account (an extension of Oaksford & Chater's, 1994, iterative counterfactual model) was also corroborated in that the generation of descending triples was demonstrated to be the dominant predictor of DG success. We focus our discussion on conceptual ideas relating to the way in which iterative counterfactual testing and contrast class identification may work together to provide a powerful basis for effective hypothesis testing.  相似文献   
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