ERP研究反映感数与计数的不同脑机制

对于较小数目的快速准确认知的“感数”现象一直是一个引人兴趣的问题,这一感数过程到底本质是什么,它与计数过程究竟是同一种加工还是分属两种不同类别,对于这个问题多年来一直存在着争论。本实验的目的在于研究感数加工的本质,运用ERP手段来探索其与计数的不同机制;并且以分心物变量为指标,研究在有分心物呈现时,感数与计数过程将会有哪些变化以及其潜在的神经机制。对14名正常青年人记录感数与计数加工过程中的事件相关脑电位（ERP）。刺激图片由位于屏幕中心的靶(白色矩形)或者靶+分心物(白色圆形)组成,靶的数目分为感数（1－3个靶）及计数（4－6）;而分心物的数目有三种水平：零（无分心物）,与靶的数目相同及两倍于靶的数目。被试计算图片上白色矩形的个数并对所得数目进行奇偶判断,最后根据奇偶性用左右手进行按键反应。行为结果表明,感数与计数的反应时在靶数目之间有显著性差异,靶数目相同时,分心物越多,则被试所需要的反应时就越长。ERP测量表明P1波幅随着靶数目的增加而增大,随着分心物数目的增加而增加;N1波潜伏期随着靶数目的增加和分心物数目增加而减小,N1波幅随着靶数目和分心物的增加而增加;P3波幅随着靶数目的增加而减小,在某些记录点具有靶效应和干扰效应。研究结果提示感数加工具有明显的分心物效应,而计数加工则不然,支持感数与计数分属两种不同功能加工过程的观点,感数加工更易受到分心物出现的干扰。     

网球运动专长对深度运动知觉影响的ERP研究

结合专家-新手范式与ERP技术,研究网球运动专长对个体深度运动知觉产生的影响。通过记录网球专家和新手各19名进行深度运动模式判断时的行为和ERP数据,比较两组个体深度运动知觉的行为反应差异和脑电特征。结果显示,网球专家组深度运动知觉的判断准确率高于新手组;新手组在球体靠近时P1(PO7点)的潜伏期比球体远离时的潜伏期长,专家组无显著性差异;专家组在球体靠近时的P2(Oz点)成分潜伏期长于球体远离时的潜伏期。结果表明,网球运动专家的深度运动知觉能力在准确性上较新手高;运动专长效应与选择性注意资源的调用以及模式识别有关;枕区P2成分可作为深度运动知觉的评价指标。     

Predictors of Child Maltreatment Potential in a National Sample of Mothers of Young Children

Although previous studies have furthered our broad ability to predict child maltreatment potential, young children remain at the highest risk for experiencing maltreatment. Thus, several variables of relevance for this population were examined. A national community sample of 158 mothers with young children between ages 1.5 and 5 years rated their young children’s temperament as well as their own temperament, emotion regulation, stress, coping, and child maltreatment potential. Young children’s mood quality as well as mothers’ mood quality, flexibility/rigidity, emotion dysregulation, parenting stress, cumulated severity of stress, and emotion-focused coping added unique incremental variance to the prediction of child maltreatment potential, accounting for 67% of the variance overall. Further, mothers’ emotion dysregulation mediated the relationship between mothers’ flexibility/rigidity and child maltreatment potential. Consequently, emotion regulation skills represent an important point of intervention for mothers of young children who are at increased risk for child maltreatment due to difficult temperament characteristics.     

多媒体学习中图文加工的认知神经机制

多媒体学习的认知理论和图文理解整合模型指出, 多媒体学习中图片和文字在早期阶段的加工遵循双通道假设, 在晚期不同表征的信息进行整合完成知识建构。理论上的探讨得到了神经科学实证研究的支持。脑成像研究发现, 图、文加工在早期的前语义阶段存在差异, 但晚期的信息整合阶段共享了同一语义系统。事件相关电位研究也发现在早期图片诱发了独特的N300成分, 而晚期图、文均诱发了N400效应。尽管现有研究已经明确了图、文共享同一语义系统, 但是信息是如何在这一系统中进行整合的还需要进一步的研究。     

An event‐related potential study on the “check operation” in the Eriksen task1

Abstract: We examined two issues for the Eriksen task with two types of stimuli, the central target letter of which was flanked with noise (e.g., HHHHH for compatible stimuli and SSHSS for incompatible stimuli). First, we examined whether or not a response‐stop function is carried out until the check operation to detect and correct erroneous response readiness has finished (Eriksen & Eriksen, 1974). Second, reaction times for incompatible stimuli are not prolonged if only identical noise stimuli are used throughout the block. This phenomenon is called the blocking effect. We then explored whether or not the blocking effect can be caused by the selective inhibition of erroneous response readiness (Eriksen & Schultz, 1979). Sixteen participants (18–29 years old) selectively pressed one of two buttons for the target letter. The results showed that the negative potential related to the response‐stop function was enlarged for incompatible stimuli. Moreover, the blocking effect was observed, while erroneous response readiness was still observable for incompatible stimuli. These results suggest that the blocking effect is caused by something other than reciprocal inhibition.     

抑郁症早醒对事件相关电位的关系研究

本研究旨在探讨抑郁症睡眠障碍早醒与事件相关电位P300的关系。 通过对22例抑郁症早醒病人、20例抑郁症非早醒病人及20例健康自愿者进行事件相关电位P300和汉密尔顿抑郁量表检测,结果发现,早醒组与对照组比较P2、N2、P3潜伏期与反应时间明显延长(P＜0.05),P2、N2、P3波幅明显降低;非早醒组与对照组比较N2、P3潜伏期与反应时间明显延长(P＜0.05),N2、P3波幅明显降低;早醒组与非早醒组比较P2、N2、P3潜伏期与反应时间明显延长(P＜0.05),N2、P3波幅明显降低。早醒组HAMD评分明显高于非早醒组(P＜0.05)。研究表明抑郁症早醒与非早醒病人均存在认知功能的损害,损害程度早醒病人比非早醒病人更为严重。     

三字字谜顿悟的时间进程和半球效应：一项ERP研究

运用事件相关电位ERPs技术, 采用猜谜任务范式, 从字谜问题解决中谜底“催化”所诱发顿悟的时间进程和半球差异两方面来探讨顿悟的认知神经机制。结果发现：在320~550ms内, “有顿悟”和“不理解”较“无顿悟”的ERP波形均有一个更大的负向偏移。在“有顿悟-无顿悟”和“不理解-无顿悟”差异波中, 该负成分的潜伏期约为380ms, 差异波的脑电峰值锁定在Cz点。半球主效应不显著, 但反应与半球交互效应显著, 其中“有顿悟”差异波的右半球平均波幅显著高于左半球和矢中部。结果表明：N380可能反映了顿悟中舍弃强外显意义而选择弱内在隐喻意义的认知抉择过程, 且右半球在“顿悟”中表现出优势效应。     

Rhythmic structure facilitates learning from auditory input in newborn infants

Rhythm and metrical regularities are fundamental properties of music and poetry - and all of those are used in the interaction between infants and their parents. Music and rhythm perception have been shown to support auditory and language skills. Here we compare newborn infants’ learning from a song, a nursery rhyme, and normal speech for the first time in the same study. Infants’ electrophysiological brain responses revealed that the nursery rhyme condition facilitated learning from auditory input, and thus led to successful detection of deviations. These findings suggest that coincidence of prosodic cue patterns and to-be-learned items is more important than the format of the input. Overall, the present results support the view that rhythm is likely to create a template for future events, which allows auditory system to predict prospective input and thus facilitates language development.     

The chemical potential and the work function of a metal film on a dielectric substrate

The chemical potential and the work function of an aluminium metal film which is in the vacuum (1) and on a dielectric substrate (2) are obtained using the model of non-interacting electrons confined by an asymmetric rectangular potential well. For the first time, these two characteristics are calculated with correct taking into account the electroneutrality condition. As a result, the values of the chemical potential and the work function tend to their bulk values upon increasing the film thickness. The presence of a dielectric substrate leads to a small shift in the values of these characteristics.     

记忆机制中再认的事件相关电位

ERP对于记忆的研究有独到之处,在研究方法是有外显的直接范式和内隐的间接范式,分别表现为ERP新旧效应和重复效应,即在刺激200ms以后的正向偏移.对于记忆提取的ERP效应已有一些理论解释,但在听觉记忆、汉字记忆以及记忆的脑内机制等方面还需要进一步的深入研究.