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Electrophysiological and functional neuroimaging evidence points to the existence of neural populations that respond strongly and selectively to the appearance of the human body and its parts. However, the relationship between ERP and fMRI markers of these populations remains unclear. Here we used a previously identified functional dissociation between two body-selective regions identified with fMRI (extrastriate body area or EBA; fusiform body area or FBA) in order to better understand the source of a body-selective N1 ERP component. Specifically, we compared the magnitude of the N1 elicited by images of fingers, hands, arms and bodies to that obtained for hierarchically-matched control stimuli. We found close agreement between the pattern of body-part selectivity exhibited by N1, and the pattern of BOLD selectivity elicited in a previous study by the same type of stimuli in EBA (in contrast to FBA). We interpret these findings as evidence for EBA as the primary generator of the body-selective N1 component. Our results are an example of the use of functional criteria to distinguish among the possible neural sources of ERP markers. 相似文献
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面孔识别异族效应的研究 总被引:2,自引:0,他引:2
异族效应是面孔识别过程中一种非常稳定的现象,表现为对本族面孔的识别与再认成绩显著高于异族面孔.脑成像研究也证实了这两类面孔在神经表征上的差异.关于该效应主要有知觉经验说与社会分类说两种理论解释,但围绕着其心理机制仍然存在着很多争议然,未来的研究需要考虑族群认同等社会-人格因素对于异族效应的影响,并注意考察本族面孔与异族面孔有提取阶段可能存在的神经活动的差异. 相似文献
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自闭症谱系障碍(ASD)是一种心理状况的谱系障碍,其症状是社交及沟通上的广泛性异常、异常局限性的兴趣和高度重复性的刻板行为。包括自闭症、亚斯伯格症候群和待分类的广泛性发展障碍3类。研究主要以事件相关电位和功能性磁共振成像两种技术为线索,通过深入分析ASD患者在面孔识别认知过程中脑的异常变化,探讨其面孔识别障碍的神经机制问题。研究表明,ASD患者面孔识别能力的损伤主要与N170、N300、P400和Nc等ERPs成份异常及梭状回面孔区和杏仁核的低激活有关。研究推论ASD患者面孔识别障碍是多个异常脑区联合作用的结果,且主要受异常脑区的数量和损伤程度的影响。 相似文献
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城镇职工医疗保险改革面临的问题与对策 总被引:1,自引:0,他引:1
我国政府已明确提出城镇职工基本医疗保险制度的改革目标,虽然改革已取得了一些进展,但距改革目标仍有相当差距。采用政治分析方法,分析了目前医改所面临的主要问题与原因,并在借鉴国际医疗保障制度改革启示的基础上,进一步探讨解决问题和推进改革进程的思路。 相似文献
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短时距知觉中的面积效应 总被引:2,自引:1,他引:1
初步探讨了短时距(1─5s)下时距刺激的面积大小和立体框架大小对时距知觉的影响及其成因。结果表明:刺激的面积大小对短时距知觉的影响极其显著;存在两种不同反应类型的被试─-大小依存者与非大小依存者,在不同反应类型的被试中刺激的立体框架大小对短时距知觉的影响不同,刺激的立体框架大小对大小依存者的短时距知觉的影响极其显著,但对非大小依存者的影响不显著。 相似文献
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In concurrent-chains schedules, pigeons prefer terminal links that provide two keys correlated with reinforcers (free choice) over those that provide only one key (forced choice), terminal-link reinforcement rates being equal. With same-size keys, free choice provides a larger area available for pecking. Preferences were examined using terminal links that differed in key number only (one or two) or key size only (small and medium or medium and large), or that equated the area of the two free-choice keys with that of the forced-choice key. Medium (standard) keys were typically preferred to small keys, but indifference was typically obtained between medium and large keys. The size preference usually overrode free-choice preference with one medium key pitted against two small keys, but free-choice preference was reliably observed with one large key pitted against two medium keys. In other words, preferences were a joint function of key number and key area, implying that free-choice preference is not reducible to preference for larger key areas. Free-choice preference requires separate keys rather than larger areas; the relevant behavioral units are the discriminated operants correlated with each terminal-link key rather than classes defined by topographical features such as area or perimeter. 相似文献
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本研究采用SCL-90、EPQ等量表,对苏中地区小学教师的人格特征与心理健康问题的关系进行了研究。研究结果表明:(1)苏中地区小学教师的人格特征与其心理健康状况显著相关。(2)苏中地区小学教师人格特征的N分、P分和E分因子进入心理健康因子的回归方程,是心理健康水平的关键性影响因素。(3)N分、P分和E分因子对心理健康的解释率为28.6%。 相似文献