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1.
To investigate the orienting of visuospatial attention, the attention type (voluntary vs. involuntary) was manipulated in a within-subject design, and event-related potentials (ERPs) were recorded in a peripheral cued, line-orientation discrimination task. A larger and later contralateral P1 and a smaller and later contralateral N1 were elicited by the valid trails relative to the invalid trails in the involuntary attention condition, whereas larger P1 and N1 were elicited by the valid trails in the voluntary attention condition. The present results provide evidence for the dissociation between voluntary and involuntary attention in one task.  相似文献   

2.
ASYMMETRIES OF HUMAN VISUAL INFORMATION PROCESS- ING ACROSS VISUAL FIELDS HAVE BEEN AN INTERESTING ISSUE IN COGNITIVE PSYCHOLOGY AND NEUROSCIENCE. IN ADDITION TO INVESTIGATIONS OF THE ASYMMETRIES BETWEEN THE LEFT AND RIGHT VISUAL FIELDS THAT ARE BELIEVED …  相似文献   

3.
一种纯内源性成分的事件相关脑电位   总被引:1,自引:0,他引:1  
闪现刺激物诱发的视觉事件相关脑电位(ERPs)中,只有那些分布在较晚时域中的波,例如P300、N400等,内源性成分占优势,并与大脑的认知活动建立了较确切联系。本文报告一种模拟人类自然阅读时的事件相关脑电位(INR-ERPs),这种INR-ERPs的开矿学特征,不受注意的自动俘获效应的影响,不论是较晚还是较早时域中的波,都几乎是纯内源性的,并显示出了明显的心理学含义,我们还发现:对于同样的认知作业  相似文献   

4.
The temporal dynamics in brain evoked by the scale of visual attention with the cues of Chinese characters were studied by recording event-related potentials (ERPs). With the fixed orientation of visual attention, 14 healthy young participants performed a search task in which the search array was preceded by Chinese characters cues, “大, 中, 小” (large, medium, small). 128 channels scalp ERPs were recorded to study the role of visual attention scale played in the visual spatial attention. The results showed that there was no significant difference in the ERP components evoked by the three Chinese characters cues except the inferoposterior N2 latency. The targets evoked P2, N2 amplitudes and latency have significant differences with the different cues of large, middle and small, while P1 and N1 components had no significant difference. The results suggested that the processing of scale of visual attention was mainly concerned with P2, N2 components, while the P1, N1 components were mainly related with the processing of visual orientation information.  相似文献   

5.
本实验采用了视听双通道伪同时呈现的oddball模式,以汉字和简单几何图形为视觉刺激,1000Hz和800Hz的纯音为听觉刺激,使用注意通道(注意和非注意条件)×刺激概率(偏差刺激概率均为15%,标准刺激的概率均为85%)的2×2因素设计,来研究视觉和听觉偏差刺激在注意和非注意条件下诱发的事件相关电位(ERPs)。实验中视觉和听觉刺激随机序列地呈现给被试(刺激间隔ISI为700~1300ms),被试被要求注意某一通道如视觉通道,而相应地忽视另一通道即听觉通道,以左右手触键反应,如左手反应视觉偏差刺激,右手反应视觉标准刺激。结果表明,听觉偏差刺激在注意和非注意条件下均诱发了类似的不匹配负波(MMN);而视觉偏差刺激在注意和非注意条件下没有诱发MMN或类似MMN的成分,这是因为视觉系统的平行加工特性和难以对视觉影像产生记忆痕迹。听觉偏差刺激在注意条件下重迭了N2b成分并跟随了P3a成分,这种重迭和跟随反映了选择注意中的定向反应。注意条件下听觉和视觉的偏差刺激诱发了较大波幅的P300成分,反映了工作记忆中的表象更新。本实验的结果支持Naatanen对MMN所做的观察,听觉偏差刺激所诱发的MMN与注意条件的无关性反映了听觉通道中感觉刺激特征的自动化加工。  相似文献   

6.
注意是听众在收听广播节目中一切心理过程(包括感觉、知觉、记忆、思维、想象等)的开端,同时它伴随并保证听众持续收听广播节目的顺利进行。从听众的注意心理的角度,从影响听众无意注意和有意注意心理的因素入手,探讨如何提高广播播音、主持技巧。  相似文献   

7.
ERP dissociations between implicit and explicit memory have been confirmed by a large amount of evidence in theories of human memory. However, similarities between the two forms of memory have scarcely been studied. A possibility is that while implicit memory and explicit memory have independ- ent components, they might additionally have shared components. To explore this question, an ERP experiment was conducted with a study-to-test paradigm, in which participants performed a "shallow" (color) study task or a "deep" (pleasant) study task, followed by either a lexical decision (implicit) test (Section 1) or a recognition (explicit) test (Section 2). An interference task was performed concurrently with either the encoding or the retrieval phase of the memory task for encoding interference condition or retrieval interference condition. We compared ERP signatures of implicit and explicit memory as a function of depth of processing or interference. Under the action of the same variables, 300―500 ms old/new ERP effects of implicit and explicit memory showed the same trend. These effects maybe all link with a perceptual representational system. 500―700 ms old/new ERP effects of the two memories were dissociated. They may probably reflect voluntary and involuntary recollection respectively. These results suggested that implicit and explicit memories are not completely independent of each other, but have both independent and shared components.  相似文献   

8.
Abstract Whether the secondary motor areas are involved in simple voluntary movements remains controversial. Differences in the neural substrates of movements with the dominant and the non-dominant hands have not been well documented. In the present study, functional magnetic resonance imaging (fMRI) was used to investigate the hemodynamic response in the primary motor cortex (M1), supple-mentary motor area (SMA) and premotor cortex (PMC) in six healthy right-handed subjects while performing a visually-guided finger-tapping task with their dominant or non-dominant hands. Significant activation was observed in M1, SMA and PMC during this externally triggered simple voluntary movement task. While dominant hand movements only activated contralateral motor areas, non-domi-nant hand movements also activated ipsilateral SMA and PMC. The results provide strong evidence for the involvement of the secondary motor areas in simple voluntarymovements, and also suggest that movements of the dominant hand primarily engage the contralateral secondary motor areas, whereas movements of the non-dominant hand engage bilateral secondary motor areas.  相似文献   

9.
采用事件相关电位(ERP)技术,记录52名大学生被试在听(正性和负性)冥想指导语的脑电波,探索冥想加工过程的神经机制与性别差异.以固定频率的声音作为线索诱发N2和P3成分,这2个成分作为探究刺激差异和注意力资源调配的标记分别在160 ms和240 ms的时间上观察到.结果表明:在正性冥想条件下,在前额叶皮层(PFC)中...  相似文献   

10.
Selective attention means perceiving and responding to information selectively, most of which are visual analyses and selection. By choosing a target that is task-relevant from stimuli array, while successfully ignoring distractorsthat are irrelevant, one can make a selection for his be-havioral goals correctly and efficiently. Recent studies have begun to focus on the dual-process mechanism of selective attention: target-excitation and distractor-inhibi- tion. A plenty of measures were used t…  相似文献   

11.
本文从篮球教学特点和学生心理特点的角度,结合教学实践,探讨在高校篮球教学中如何运用注意规律增强教学效果的问题.重点分析了无意注意和有意注意规律组织教学,以及两者转换运用的问题.  相似文献   

12.
We investigated the reappraisal and the time course of negative emotion regulation by performing event-related potential (ERP) recordings. We found that negative pictures elicited more positive P2 and late positivity potential (LPP) deflections than neutral pictures. This effect occurred between 150-2000 ms post-stimulus. Compared to the emotion maintaining condition, the emotion enhancing condition was associated with higher arousal ratings and displayed increased P2 and LPP amplitudes. The decrease condition was also associated with reduced picture-induced arousal; however, it led to increased P2 and LPP amplitudes. Furthermore, when compared with the maintain condition, both the enhancing and decrease conditions significantly enhanced LPP in the early stage (350-750 ms). Compared to previous studies using western subjects, the negative emotion LPP effects of the present study were shorter in duration and the decrease-emotion condition elicited larger LPPs.  相似文献   

13.
The current work investigated the neural correlates of visual perceptual learning in grating orientation discrimination by recording event-related potentials (ERPs) from human adults. Subjects were trained with a discrimination task of grating orientation in three consecutive training sessions within 2 h. While reaction times (RTs) were shortened gradually across training sessions, the N1 was decreased and the P2 was increased over the parietal and occipital areas. A broadly distributed P3 was increased along with more practices. In addition, the time course of learning reflected in the P2 and P3 amplitudes was in line with the changes of reaction times and exhibited a stable level during later training. The impli- cations of these results to the neural mechanisms subserving perceptual learning were discussed.  相似文献   

14.
运用事件相关电位(ERPs)技术, 采用学习-再认的实验范式, 考察38名大学生(21名男生和17名女生)对女性面孔吸引力再认记忆的认知神经机制。结果发现大学生对女性面孔吸引力的记忆偏好存在性别差异, 再认任务中有吸引力的女性面孔诱发了男性更负的早期ERP成分(N90, N220和N300), 而对女性的效应并不显著。这可能与两性在遗传基因、性激素、大脑结构与功能上的不同有关。进一步对男性的记忆特点进行分析发现, 内隐记忆效应在N80和LPC(300~600 ms)上表现显著, 其最强效应出现在中央区和顶区; 外显记忆效应在P170和LPC(400~600 ms)上表现显著, 其最强效应出现在前额区和额区。表明男性对有吸引力女性面孔的记忆偏好效应更大, 且内隐和外显记忆的脑机制在单一的再认任务中产生了分离。  相似文献   

15.
听觉脑机接口技术为视觉通路存在障碍的闭锁综合征患者提供了与外界交流的新通道.为了使空气传导通路受损的病患也能应用此项技术,本文将声音骨传导方式引入到听觉脑机接口实验研究中.本研究设计了左右耳分别呈现不同声音序列的双耳分听实验范式,对骨传导及空气传导方式所诱发脑电信号进行了特征提取和分类比较.实验结果表明两种传导方式下靶刺激均可稳定的诱发出N200与P300电位,骨传导方式下,N200的幅值较空气传导方式更显著.两种方式都获得较高的分类正确率,均可用于听觉脑机接口系统,且骨传导方式优于空气传导方式.  相似文献   

16.
为工业企业听力保护计划制定、人机工程学设计及劳动者烦恼度缓解等提供客观的生理依据,分析了生产性噪声对工作人员脑认知的影响.采集自愿者在90 d B(A)的稳态机械性噪声刺激以及安静状态下的脑电信号,建立事件相关脑电位ERP中N1(N100)波的幅值脑地形图及P2(P200)波幅值的脑地形图,对ERP信号进行时频分析.结果表明噪声刺激与静音状态相比,ERP在N1波的幅值明显减少,而在P2波幅值变化呈相反趋势明显增加.噪声刺激下被试额区导联的N1幅值显著减小,P2幅值显著增加,表明高声压级生产性噪声导致被试烦躁、注意力分散,并干扰了认知能力.  相似文献   

17.
为研究与飞行任务相关的认知负荷对听觉事件相关电位的影响, 采用14名被试者开展飞行模拟实验, 完成基于不同认知负荷水平的仪表监视任务。同时, 由耳机双侧呈现oddball模式下的听觉刺激, 引导被试者关注飞行模拟任务, 忽略听觉刺激。记录听觉事件相关电位失匹配负波(mismatch negativity, MMN)、N1和P2作为认知负荷的评价指标。实验结果表明认知负荷对额叶MMN的影响显著, MMN平均波幅在高认知负荷下显著增强, 表明被试者对任务不相关信息的自动加工能力提高, 且MMN平均波幅与模拟飞行期间被试者对异常信息的正确探测率正相关。提示额中央区的MMN对于与飞行任务相关的认知负荷具有较好的敏感性, 并可能用于复杂飞行任务的认知负荷水平评价。但是, 实验结果也表明认知负荷对早期听觉成分N1, P2以及颞叶MMN的影响不明显, 在一定程度上说明了听觉事件相关电位在评价与飞行任务相关的认知负荷时所表现出的复杂效应。  相似文献   

18.
Event-related potential (ERP) was used to examine the interactions between working memory and se- lective attention. We combined two unrelated tasks, one requiring working memory and the other se- lective attention, which were performed by some undergraduates. The ERP results revealed that both congruent and incongruent stimuli in the selective attention task evoked an N400 component, reaching the peak point at around 500 ms. The N400 evoked by incongruent stimuli was more negative than that of congruent, which indicated the difference of semantic N400. Furthermore, working memory load had a significant influence on the N400 evoked by selective attention task in parietal region. And working memory load showed difference in the ERPs of working memory retrieval in central and parietal regions. The ERPs of probe under high working memory load were more positive from 350 to 550 ms post-stimulus; however, stimulus type of selective attention had no influence on working memory re- trieval. The present study shows that working memory does not play a major role in the selective at- tention, especially in ignoring distracter, but it influences the performance of the selective attention as the background. The congruency of target and distracter in the selective attention task does not influ- ence the working memory retrieval.  相似文献   

19.
假设社会环境政治稳定、经济稳定、个人身体健康状况稳定,个人社会危机函数的变量可以按二分法从内因、外因上分析确定.内因选取智商I、情商em、知识存量k、道德(或文化)m.外因选取对主体相应危机事件的有效影响群体,假设对危机事件有效影响群体总数为G,主体在危机事件的影响力即得票数为A,对主体的积极影响力即主体的利益集团总票数为P,对主体的消极影响力即主体的反对派集团总票数为N,则A/G和N/P 看成个人社会危机函数的另2个变量,危机函数可写为c4=f(A/G,I,em,k,m;N/P).简化研究可用c4=f(A/G,N/P).危机系数用ε=W1/W2或ε=U1/U2表示,W1为是主体现期如没有危机应得的福利水平,W2是主体现期危机状态下实际的福利水平,U代表效用水平,危机系数用来测度实际危机水平.  相似文献   

20.
任务的分解是实现多主体系统的关键,运用形式化的方法对任务分解进行描述和验证是十分必要的。对于一般的任务逻辑分解表达式,利用Petri网对任务的分解进行建模,得到任务分解Petri网,进而通过剔除不合理的任务分解结构得到任务有效分解的Petri网系统。通过检查任务有效分解的Petri网的存在与否,可以判断任务的分解结构是否有效。另外,对于任意一个有限的P/T网系统,给出了判断是否存在无效任务分解的充分条件,从而论证了在任务有效分解的Petri网系统中只存在一级活变迁。将任务分解的有效性判断与Petri网活性分析联系起来,实现了多主体系统的一个亟待解决的基础性问题。  相似文献   

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