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961.
Mood in humans is a complex phenomenon that integrates emotion (e.g. happiness and sadness), cognition, perception, ideation, and action in a coherent manner. In bipolar disorder extremes of mood (up or down) occur outside the normal range, in which all the above functions are coherently affected. Mood is controlled by a series of separate but interactive brain circuits that involve much of the brain, but particularly the limbic system. The question addressed in this paper is whether the coordination of all these separate systems into one coherent functional mood is mediated by non-linear dynamics acting between these systems as equal participants; or whether it is affected by a single master regulator controlling the others. The possible roles, as master regulators, of non-linear dynamically linked populations of neurons, and of the C1–C3 adrenergic nuclei in the medulla is discussed.  相似文献   
962.
Comparing the phenomenology, neurochemical pathology, and psychopharmacology of hallucinations and dreaming is limited by the available data. Evidence to date reveals no simple correspondence between the two states. Differences in the phenomenology of visual hallucinations and the visual component of dreams may reflect variations in visual context acting on the same underlying mechanism – the minimal visual input during dreaming contrasts with the more substantial perceived context in hallucinations. Variations in cholinergic, dopaminergic and serotonergic neurotransmitter function during sleep and during hallucinations in Lewy body dementias, together with relevant drug effects suggest that, on the whole, different, potentially opposite, changes characterise the two states. A similar analysis of other psychotic features in Lewy body dementia and other disorders suggests that, in contrast to hallucinations, there may be more convincing parallels between dreaming and delusional states.  相似文献   
963.
Studies showing human behavior influenced by subliminal stimuli mainly focus on implicit processing per se, and little is known about its interaction with explicit processing. We examined this by using the Simon effect, wherein a task-irrelevant spatial distracter interferes with lateralized response. Lo and Yeh (2008) found that the visual Simon effect, although it occurred when participants were aware of the visual distracters, did not occur with subliminal visual distracters. We used the same paradigm and examined whether subliminal and supra-threshold stimuli are processed independently by adding a supra-threshold auditory distracter to ascertain whether it would interact with the subliminal visual distracter. Results showed auditory Simon effect, but there was still no visual Simon effect, indicating that supra-threshold and subliminal stimuli are processed separately in independent streams. In contrast to the traditional view that implicit processing precedes explicit processing, our results suggest that they operate independently in a parallel fashion.  相似文献   
964.
965.
Evidence indicates that systemic administration of lipopolysaccharide (LPS) induces brain inflammation, ultimately resulting in cognitive deficits. Ursolic acid (UA), a plant-derived pentacyclic triterpenoid, is well known to possess multiple biological functions, including antioxidant, anti-tumor and anti-inflammatory activities. In the present study, we assessed the protective effect of UA against the LPS-induced cognitive deficits in mice. We found that UA significantly improved cognitive deficits of LPS-treated mice in open field, step-through passive avoidance and Morris water maze tasks. One potential mechanism of this action was attributed to the decreased production of pro-inflammatory markers including COX-2, iNOS, TNF-α, IL-1β, IL-2 and IL-6 in LPS-treated mouse brain. Mechanistically, UA markedly inhibited LPS-induced IκBα phosphorylation and degradation, NF-κB p65 nuclear translocation and p38 activation in mouse brain, but did not affect the activation of TLR4, MyD88, ERK, JNK and Akt. Taken together, these results suggest that UA may be useful for mitigating inflammation-associated brain disorders by inhibiting pro-inflammatory factors production, at least in part, through blocking the p38/NF-κB signaling pathways.  相似文献   
966.
How should we assess the comparability of driving on a road and “driving” in a simulator? If similar patterns of behaviour are observed, with similar differences between individuals, then we can conclude that driving in the simulator will deliver representative results and the advantages of simulators (controlled environments, hazardous situations) can be appreciated. To evaluate a driving simulator here we compare hazard detection while driving on roads, while watching short film clips recorded from a vehicle moving through traffic, and while driving through a simulated city in a fully instrumented fixed-base simulator with a 90 degree forward view (plus mirrors) that is under the speed/direction control of the driver. In all three situations we find increased scanning by more experienced and especially professional drivers, and earlier eye fixations on hazardous objects for experienced drivers. This comparability encourages the use of simulators in drivers training and testing.  相似文献   
967.
To assist road safety professionals in developing effective strategies to combat the risk associated with driving while fatigued, a survey was administered to 1000 Australian drivers. Participants reported their past behaviours in regards to driving while sleepy and their perceptions of risk associated with driving fatigued as compared to speeding and driving under the influence of alcohol. Although participants appeared to be aware of the substantial risk associated with driving while sleepy, many drivers reported that they frequently drive when sleepy. Age and gender comparisons, revealed that risk taking behaviour in regards to driving while sleepy is occurring across all age groups and in both male and female drivers. Overall young to middle age drivers and male drivers reported the highest frequency of driving while sleepy and reported the lowest perceived personal risk in regards to driving while sleepy.  相似文献   
968.
This article examines the professional valorisation of gender-typed traits. In the study, participants should assess masculine, feminine and androgynous profiles in a set of professional contexts obtained by the crossing of social status (high versus low), gender (masculine versus feminine) and sector (production versus maintenance) of occupations. Consistent with a gender- typed trait matching model, the results showed that masculine profiles were the most valued ones in the most masculine occupations, feminine profiles were mostly valued in the most feminine occupations while androgynous profiles were the most valued in gender ambiguous occupations. Of particular interest was the fact that the perception of occupations’ gender was a function of the interaction between the gender and the sector of occupations (i.e.: the most masculine occupations were those that were stereotypically masculine and belonging to the production sector; the most feminine were those that were stereotypically feminine and belonging to the maintenance sector; the stereotypically masculine and maintenance occupations as the stereotypically feminine and production occupations were perceived as less gender typed).  相似文献   
969.
MRMLC模型是一种常见的动态评估项目反应理论模型。本研究结合小学儿童图形推理能力发展的特点,采用前测-干预-后测的动态评估模式,对来自江西省北部的四到六年级共177名儿童的图形推理能力进行了基于MRMLC模型的动态评估。研究结果表明通过动态评估我们不仅可以获知儿童图形推理能力的当前水平;而且,还可以进一步分析和比较儿童在各测量情景所测的潜在水平。  相似文献   
970.
王峥芳  周雅  刘翔平 《心理科学》2011,34(6):1372-1378
目的:研究旨在考察数学学习中的流畅体验,探讨流畅体验、内/外动机、数学焦虑及数学成绩的关系。方法:招募296名高中生,在数学月考后完成自编考试流畅体验量表、学习动机量表、数学焦虑量表。结果:路径分析表明,存在四条显著路径,即内部动机→流畅状态→数学成绩;数学焦虑→流畅状态→数学成绩;外部动机→流畅状态→数学成绩;外部动机→数学成绩。结论:只有通过考试过程中的流畅体验,内部动机和数学焦虑才能影响考试成绩。  相似文献   
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