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21.
杭玲 《全科护理》2021,19(6):856-858,864
目的:探讨重症肺炎患儿父母反刍性沉思水平,探讨其影响因素。方法:采用便利抽样法,于2017年6月—2019年6月抽取某三级甲等医院符合纳入标准的110例重症肺炎患儿父母为调查对象,采用一般资料调查表、中文版反刍性沉思评分表(C-ERRI)对其进行调查。结果:110例重症肺炎患儿父母反刍性沉思总得分(31.60±6.64)分。多元线性回归分析显示,家庭角色、文化水平和家庭收入为侵入性沉思水平的独立影响因素;家庭角色和文化水平为目的性沉思的独立影响因素。结论:重症肺炎患儿父母侵入性反刍性沉思水平较高,目的性反刍性沉思水平适中。临床护理人员应该重视家庭角色、文化程度、家庭收入对父母反刍性沉思水平的影响,制定有针对性的心理指导策略,从而促进其父母能长期保持健康的心理水平。  相似文献   
22.
The residual consciousness of unconscious patients can be detected by studying the P300, a wave among event-related potentials. Previous studies have applied tones, the subject's name and other names as stimuli. However, the results were not satisfactory. In this study, we changed the constituent order of subjects' two-character names to create derived names. The subject's derived names, together with tones and their own names, were used as auditory stimuli in event-related potential experiments. Healthy controls and unconscious patients were included in this study and made to listen to these auditory stimuli. In the two paradigms, a sine tone followed by the subject's own name and the subject's derived name followed by the subject's own name were used as standard and deviant stimuli, respectively. The results showed that all healthy controls had the P300 using both paradigms, and that the P300 in the second paradigm had a longer latency and two peaks. All minimally conscious state patients had the P300 in the first paradigm and the majority of them had the P300 in the second paradigm. Most vegetative state patients had no P300. Patients who showed the P300 in the two paradigms had more residual consciousness, and patients with the two-peak P300 had a higher probability of awakening within a short time. Our experimental findings suggest that the P300 event-related potential could reflect the conscious state of unconscious patients.  相似文献   
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24.
Long-term cultural experiences influence neural response to one''s own and friend''s faces. The present study investigated whether an individual''s culturally specific pattern of neural activity to faces can be modulated by temporary access to other cultural frameworks using a self-construal priming paradigm. Event-related potentials were recorded from British and Chinese adults during judgments of orientations of one''s own and friend''s faces after they were primed with independent and interdependent self-construals. We found that an early frontal negative activity at 220–340 ms (the anterior N2) differentiated between one''s own and friend''s faces in both cultural groups. Most remarkably, for British participants, priming an interdependent self-construal reduced the default anterior N2 to their own faces. For Chinese participants, however, priming an independent self-construal suppressed the default anterior N2 to their friend''s faces. These findings indicate fast modulations of culturally specific neural responses induced by temporary access to other cultural frameworks.  相似文献   
25.
Social exclusion is known to cause alterations in neural activity and perceptions of social distress. However, previous research is largely limited to examining social interactions as a unitary phenomenon without investigating adjustments in neural and attentional processes that occur during social interactions. To address this limitation, we examined neural activity on a trial-by-trial basis during different social interactions. Our results show conflict monitoring neural alarm activation, indexed by the N2, in response to specific exclusionary events; even during interactions that are inclusionary overall and in the absence of self-reported feelings of social pain. Furthermore, we show enhanced attentional activation to exclusionary events, indexed by the P3b, during exclusionary, compared with inclusionary, interactions, and this P3b activation was associated with self-reported social distress following prolonged social exclusion. Finally, both the N2 and P3b showed larger amplitudes in the earlier stages of exclusion compared with later stages, suggesting heightened early sensitivity for both components. Together, these findings provide novel insights into the dynamic neural and perceptual processes of exclusion that exist during social interactions and the relationship between discrete events within interactions and the more general contexts of the social interactions.  相似文献   
26.
目的评价3R疗法对轻、中度阿尔茨海默病患者认知功能和血浆β淀粉样蛋白_(1-42)(Aβ_(1-42))的影响。方法选择轻、中度阿尔茨海默病患者34例,随机分为2组,每组17例。对照组给予药物常规治疗,治疗组在药物常规治疗基础上,采用3R疗法进行认知功能训练。测定血浆Aβ_(1-42),并进行神经心理学指标检查:简易智能状态检查量表、日常生活活动能力量表(ADL)、社会功能活动调查(FAQ)、神经精神量表(NPI)以及事件相关电位P300的基线评定,在开始实施训练后的第3、6个月时,分别对患者进行各项指标的评定与分析。结果治疗组经过3、6个月的3R治疗后,ADL、FAQ、NPI评分较治疗前明显减低,且明显低于对照组(P<0.05,P<0.01);P300潜伏期明显缩短,波幅明显增加(P<0.01);治疗组经过6个月的3R治疗后,血浆Aβ_(1-42)含量较治疗前明显下降,且较对照组明显下降(p<0.05)。结论 3R疗法能有效提高阿尔茨海默病患者生活自理能力、社会活动能力,从而延缓认知功能减退;3R治疗后,认知功能改善可能与血浆Aβ_(1-42)含量变化有关。  相似文献   
27.
PurposeThe dorsal attention network (DAN) and the ventral attention network (VAN) are known to support visual attention, but the influences of ocular dominance on the attention networks are unclear. We aimed to explore how visual cortical asymmetry of the attention networks correlate with neurophysiological oscillation and connectivity markers of attentional processes.MethodsAn oddball task with concentric circle stimuli of three different sizes (i.e., spot size of 5°, 20°, or 30° of visual angle) was used to vary task difficulty. Event-related oscillations and interareal communication were tested with an electroencephalogram-based visual evoked components as a function of ocular dominance in 30 healthy subjects.ResultsAccuracy rates were higher in the dominant eyes compared with the nondominant eyes. Compared with the nondominant eyes, the dominant eyes had higher theta, low-alpha, and low-beta powers and lower high-alpha powers within the nodes of VAN and DAN. Furthermore, visual information processed by the dominant and nondominant eye had different fates, that is, the dominant eyes mainly relied on theta and low-alpha connectivity within both the VAN and the DAN, whereas the nondominant eyes mainly relied on theta connectivity within the VAN and high-alpha connectivity within the DAN. The difference in accuracy rate between the two eyes was correlated with the low-alpha oscillations in the anterior DAN area and low-alpha connectivity of the left DAN.ConclusionsThe ocular dominance processing and interareal communication reveal a cortical asymmetry underlying attention, and this reflects a two-way modulatory mechanism within attention networks in the human brain.  相似文献   
28.
目的:探讨酒精所致精神障碍患者事件诱发电位P300的特点。方法:对30例酒精所致精神障碍患者(研究组)和31名正常人(正常对照组)进行事件诱发电位P300的检测,并与正常对照组进行配对t检验和相关分析。结果:与正常对照组比较,酒精所致精神障碍患者P300潜伏期N2、P3显著延长(t=2.318,沁2.335;P〈0.05);P300波幅N1、N2、P3显著降低(t=-2.414;t=-2.613,t=-4.453;P〈0.05或P〈0.001)。相关分析显示,酒精所致精神障碍患者饮酒年限以及饮酒量与P300潜伏期、波幅之间无明显相关(r=-0.128~-0.274,r=-0.075~0.328;P均〉0.05)。结论:酒精所致精神障碍患者存在认知功能损害,P300可作为酒精所致精神障碍患者检测项目之一。  相似文献   
29.
Cognitive functions are often studied using eventrelated potentials(ERPs)that are usually estimated by an averaging algorithm.Clearly,estimation of single-trial ERPs can provide researchers with many more details of cognitive activity than the averaging algorithm.A novel method to estimate single-trial ERPs is proposed in this paper.This method includes two key ideas.First,singular value decomposition was used to construct a matrix,which mapped singletrial electroencephalographic recordings(EEG)into a low-dimensional vector that contained little information from the spontaneous EEG.Second,we used the theory of compressed sensing to build a procedure to restore single-trial ERPs from this low-dimensional vector.ERPs are sparse or approximately sparse in the frequency domain.This fact allowed us to use the theory of compressed sensing.We verified this method in simulated and real data.Our method and dVCA(differentially variable component analysis),another method of single-trial ERPs estimation,were both used to estimate single-trial ERPs from the same simulated data.Results demonstrated that our method significantly outperforms dVCA under various conditions of signal-to-noise ratio.Moreover,the single-trial ERPs estimated from the real data by our method are statistically consistent with the theories of cognitive science.  相似文献   
30.
负性情绪刺激的反应启动效应事件相关电位的实验研究   总被引:3,自引:0,他引:3  
目的:许多研究观察到,有机体对负性情绪刺激的反应比对中性或正性刺激快,本研究应用事件相关电位中的单侧化准备电位将反应时划分为刺激加工阶段和反应准备阶段,从而得以直接观察负性刺激的反应启动效应。方法:本研究选取国际情感图片系统的正、中、负性图片作为剌激材料,以正常大学生为被试,令其按键表示对图片情绪属性的判断,同时记录脑电。结果:正、负性情绪刺激引起的刺激锁定单侧化准备电位的潜伏期比中性条件下的潜伏期缩短,观察反应锁定单侧化准备电位的潜伏期可见,负性刺激引起的潜伏期显著短于中性和正性条件。结论:对情绪性刺激的心理加工评价过程较短,观察反应锁定单侧化准备电位的潜伏期可见,负性剌激引起的潜伏期显著短于中性和正性条件,表明负性刺激具有反应启动效应.  相似文献   
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