威胁性情绪对时间知觉的影响——基于情绪动机理论的视角

本研究从动机角度探讨两种特定的威胁性情绪(愤怒、恐惧)对时间知觉的影响。分别采用情绪面孔图片(实验1)和身体图片(实验2),通过时间比较任务(实验1、实验2)和时间估计任务(实验3),均发现了时间知觉在愤怒和恐惧这两种威胁性情绪影响下的差异：与中性情绪相比,愤怒引起主观时间变短,恐惧引起主观时间变长。研究揭示了情绪动机对时间知觉的影响,趋近动机下主观时间变短,回避动机下主观时间变长。     

左侧背外侧前额叶在程序性运动学习中的作用

程序性运动学习包括序列学习和随机学习。神经影像学研究表明背外侧前额叶皮层(DLPFC)和初级运动皮层(M1)在程序性运动学习中发挥重要作用, 但DLPFC和M1之间的联通性及其与不同程序性运动学习的关系尚不明确。本研究采用连续反应时间任务, 结合经颅磁刺激(TMS)方法, 探讨左侧DLPFC到M1的联通性在不同程序性运动学习中的差异。实验1采用两连发TMS探测DLPFC到M1的最佳投射时间点; 实验2, 被试分为2组, 分别进行序列学习和随机学习, 在学习前、后采集行为学数据, 以及M1的运动诱发电位和DLPFC-M1联通性的电生理学数据。行为学结果发现序列学习组的学习效果更佳; 电生理学结果发现, 两组被试学习前、后M1的运动诱发电位均未发生改变; 在最佳时间投射点、适当刺激强度下, 序列学习组DLPFC-M1联通性发生改变, 且与学习成绩相关, 而随机学习组没有改变。结果说明DLPFC到M1的联通性增强可能是序列学习成绩更佳的重要原因, 这一结果从电生理角度为DLPFC在运动学习中的作用提供了重要证据。     

背外侧前额叶在安慰剂效应中的作用：社会情绪调节研究

为考察安慰剂效应在情绪调节中的脑机制,本研究以社会排斥图片为情绪诱发材料诱发社会疼痛,采用经颅磁刺激技术(transcranialmagneticstimulation,TMS)激活背外侧前额叶(dorsolateralprefrontalcortex,DLPFC),并使用事件相关电位观测TMS对安慰剂下调社会疼痛的影响。实验以“TMS组别”(DLPFC组、控制组)为被试间变量,“安慰剂条件”(安慰剂、非安慰剂)为被试内因素。结果发现, DLPFC组(n=50)比控制组(n=50)在安慰剂条件下报告的负性情绪更弱,反映情绪体验强度的晚正成分的波幅也更低,上述组间差异在非安慰剂条件不显著。结果还表明,DLPFC组比控制组更相信安慰剂的效果,愿意花更多的钱来购买安慰剂。此外相关结果发现,由DLPFC激活导致的安慰剂效应增强可有效降低社交焦虑倾向被试的负性社会情绪。本研究是结合脑调控和脑观测技术探讨安慰剂情绪调节脑机制的首次尝试,研究发现不但揭示了DLPFC在安慰剂调节情绪过程中的重要因果作用,还为临床治疗以情绪失调为主要症状的抑郁焦虑等精神障碍患者提供了脑调控干预的可行性脑靶点。     

数量对时间知觉的影响——来自汉语数字的证据

本研究的目的在于探讨汉语数字对时间知觉的影响。采用二分试验程序,以400ms和1200ms作为标准短时间和标准长时间,三个实验中屏幕分别呈现阿拉伯数字(1、5和9),汉语小写数字(一五和九),汉语大写数字(壹伍和玖),让被试估计数字的呈现时间更接近于标准长时间还是标准短时间。结果显示三种实验条件下被试均具有低估小数字的呈现时间和高估大数字呈现时间的倾向。这个结果表明汉语数字也会对时间知觉产生影响,汉字形式的数字可以纳入到综合的数量理论体系之中。     

数目及其呈现方式在不同范围内对时间知觉的影响

采用时间比较法,考察数目及其呈现方式对时间知觉的影响。任务中,首先呈现标准时距,此时变化刺激的数目或呈现方式,然后呈现比较时距,被试的任务是判断比较时距比标准时距长还是短。实验1和实验2分别采用1秒内和1秒以上的时间,结果发现： 1秒内的时间加工中,刺激一个一个连续呈现时,小数引起标准时距的低估,大数导致标准时距的高估,而同时呈现时,刺激的数目对知觉到的时间无影响;数目及其呈现方式影响计时的准确性,而对计时的变异性和敏感性无影响。时间在1秒以上,同时呈现和连续呈现条件下,刺激的数目影响知觉到的时间;计时的     

权力与耐心：权力感对时间知觉与跨期决策的影响

已有研究发现高权力感会使个体更耐心,更偏好延迟的大奖励。本研究假设高权力感导致耐心也会体现在时间知觉上,并且时间知觉是高权力导致耐心的心理机制。研究通过考察权力感对时间知觉与跨期决策的影响,以及时间知觉的中介作用对此假设进行了检验。实验1通过回忆法启动权力感,检验权力感对时间知觉的影响;实验2采用角色扮演法启动权力感,考察权力感对跨期决策的影响,并检验时间知觉的中介作用。结果发现：相比低权力感,高权力感个体感觉时间过得更快,进而使个体在跨期决策中更偏好延迟的大奖励,权力感并不直接影响跨期决策。研究揭示了权力感对时间知觉的影响,为权力感影响耐心行为的解释提供了时间知觉的新视角。     

情绪对时间知觉的影响

研究了情绪唤醒度和愉悦度对时间知觉的影响及其机制.以53名大学生为被试,采用中国情绪图片系统为情绪诱发材料,使用时间两分法和泛化法考察唤醒和注意机制对时间知觉的影响.结果表明:在短时距下,(1)唤醒度和愉悦度对时间知觉的影响可能是独立的,两个实验中交互作用都不显著;(2)情绪主要通过唤醒机制影响时间知觉,被试在高唤醒情绪下知觉到的时间显著长于在低唤醒情绪下知觉到的时间.     

冠心病人的时间知觉和联想(应激)词反应特点的探讨

本实验是关于心血管病人心身反应特点的一系列研究工作的一部分。用时间知觉实验和联想词反应实验,探讨冠心病人对时间估计的特点和对于具有挑逗性的联想刺激词的反应特点及其与冠心病人的主要行为类型特征的关系。研究结果表明,冠心病人在时间知觉实验中对时间的估计均较常人相对地长.而在联想词反应实验中对挑逗性刺激词的反应量明显地高于常人。     

时间知觉与估计的认知理论综述

本文回顾时间知觉与估计的实验研究 ,总结该领域的国内外研究结果 ,对该领域的各主要认知模型作了较全面的考察和评述 ,并进一步探讨了时间认知领域研究的今后发展 ,尤其是时间知觉与估计研究的脑电研究思路。     

5至8岁儿童时间知觉的实验研究

儿童的时间知觉是怎样发展起来的?发展过程中有哪些特点?经历哪些主要阶段?这是发展心理学要研究的课题之一。在国外,斯迈思,戈德斯通(E.J.Smythe,1957, S.Gold-stone,1958)等人曾研究过6—14岁儿童对以秒计的主动时间估计和被动时间估计,认为8—14岁儿童对短时间的估计比较准确,时间观念已渐趋稳定,并能利用有关的参考     

Recognition memory and prefrontal cortex: dissociating recollection and familiarity processes using rTMS

Recognition memory can be supported by both the assessment of the familiarity of an item and by the recollection of the context in which an item was encountered. The neural substrates of these memory processes are controversial. To address these issues we applied repetitive transcranial magnetic stimulation (rTMS) over the right and left dorsolateral prefrontal cortex (DLPFC) of healthy subjects performing a remember/know task. rTMS disrupted familiarity judgments when applied before encoding of stimuli over both right and left DLPFC. rTMS disrupted recollection when applied before encoding of stimuli over the right DLPFC. These findings suggest that the DLPFC plays a critical role in recognition memory based on familiarity as well as recollection.     

聋生1秒以下与以上的视时距知觉研究

采用时距二分任务,探讨聋生在视觉通道的1s以下和1s以上时距知觉的特点。结果发现,在1s以下条件下,聋生时距判断准确性低于普通学生;聋生CNV峰值与LPCt波幅低于普通学生,CNV潜伏期短于普通学生,LPCt峰值潜伏期长于普通学生。在1s以上条件下,聋生时距判断准确性高于普通学生;聋生N1、P2、CNV与LPCt成分各项指标与普通学生均没有显著差异。这说明,听觉丧失损伤了聋生1s以下的时距记忆与决策过程,支持了普遍缺陷假设;但听觉丧失未对聋生1s以上时距加工产生显著影响,支持了感觉补偿机制。因此,时距长度在听觉丧失对视觉时距知觉的影响中具有调节作用,为时间认知的分段综合模型提供了新的支持证据。     

不同时距加工机制的比较:来自ERP的证据(Ⅰ)

采用事件相关电位的方法分析了不同时距加工机制的差异。实验采用时间两分任务,要求被试形成短(400ms)和长(1600ms)的时间判断标准,然后对7个刺激系列进行短、长的判断。结果表明时间知觉过程可以诱发出一种类似于CNV的慢性负波。对于400ms的短时距加工存在显著的半球效应,右半球的波幅显著高于左半球。1600ms的时距加工没有表现出明显的半球效应。不同时距的加工存在显著的差异。1600ms比400ms加工诱发出更大的CNV波幅。     

Dorsolateral prefrontal cortex mediates working memory processes in motor skill learning

Neuroimaging studies have shown that the dorsolateral prefrontal cortex (DLPFC) is recruited during motor skill learning, which suggests the involvement of the DLPFC in working memory (WM) processes, such as selection and integration of motor representations temporarily stored in WM. However, direct evidence linking activation of the DLPFC to WM storage and manipulation during motor skill learning in real-time is rare. In this study, we conducted two experiments to investigate the causal role of DLPFC activity in WM storage and manipulation during motor skill learning under low and high WM-demand conditions. Participants received continuous theta burst stimulation (cTBS) and sham stimulation (crossover design) over the left DLPFC (experiment 1) or right DLPFC (experiment 2). Before and after stimulation, participants in both experiments performed a sequential finger-tapping (SFT) task containing repeated sequence (low-WM demand) and non-repeated sequence (high-WM demand) conditions which are used to study WM processes. The number of correct sequences (NoCS) and reproduction error rate were analyzed. Learning gains in NoCS improved significantly with the practice for both sequence types in the presence of either stimulation type. Compared to sham stimulation, cTBS over the left DLPFC resulted in significantly reduced learning gains in NoCS for non-repeated sequences. These results suggest that the left DLPFC contributes to WM manipulation during motor skill learning.     

一种混合型前瞻记忆的干扰效应的神经机制

采用3（任务类型）×2（时段）被试内实验设计,对比一种混合型前瞻记忆（MPM）和基于事件的前瞻记忆（EBPM）在不同时段对进行中任务的干扰效应的神经机制。结果表明,在目标出现的时段,MPM对进行中任务有干扰效应,额区电极最活跃,额区电压最高,而在非目标时段MPM无干扰效应,但刺激出现后200-300ms额区电极较活跃。说明前瞻记忆任务在大脑中可能处于较高的激活状态,额叶灵活地调配意识的不同状态在前瞻记忆加工中参与的程度和时段。     

Developmental differences in prefrontal activation during working memory maintenance and manipulation for different memory loads

The ability to keep information active in working memory is one of the cornerstones of cognitive development. Prior studies have demonstrated that regions which are important for working memory performance in adults, such as dorsolateral prefrontal cortex (DLPFC), ventrolateral prefrontal cortex (VLPFC), and superior parietal cortex, become increasingly engaged across school-aged development. The primary goal of the present functional MRI study was to investigate the involvement of these regions in the development of working memory manipulation relative to maintenance functions under different loads. We measured activation in DLPFC, VLPFC, and superior parietal cortex during the delay period of a verbal working memory task in 11-13-year-old children and young adults. We found evidence for age-related behavioral improvements in working memory and functional changes within DLPFC and VLPFC activation patterns. Although activation profiles of DLPFC and VLPFC were similar, group differences were most pronounced for right DLPFC. Consistent with prior studies, right DLPFC showed an interaction between age and condition (i.e. manipulation versus maintenance), specifically at the lower loads. This interaction was characterized by increased activation for manipulation relative to maintenance trials in adults compared to children. In contrast, we did not observe a significant age-dependent load sensitivity. These results suggest that age-related differences in the right DLPFC are specific to working memory manipulation and are not related to task difficulty and/or differences in short-term memory capacity.     

不同时距条件下面孔表情知觉的时间整合效应

通过把面孔表情分割成三部分,按照不同的时间间隔以及不同的呈现时间相继呈现,考察了被试对面孔表情的时间整合效果,以此探讨时间整合的加工过程和影响因素。结果发现：（1）面孔表情的时间整合效果受时间结构和刺激材料的影响。（2）分离呈现的面孔表情能否进行时间整合与SOA的大小有关。（3）面孔表情的时间整合存在类型差异。（4）面孔表情的时间整合是在一个有限的视觉缓冲器内进行的,图像记忆和长时记忆与面孔表情的时间整合过程关系密切。     

Time processing in children with Tourette’s syndrome

Background

Tourette syndrome (TS) is characterized by dysfunctional connectivity between prefrontal cortex and sub-cortical structures, and altered meso-cortical and/or meso-striatal dopamine release. Since time processing is also regulated by fronto-striatal circuits and modulated by dopaminergic transmission, we hypothesized that time processing is abnormal in TS.

Methods

We compared time processing abilities between nine children with TS-only (i.e. without major psychiatric comorbidities) and 10 age-matched healthy children, employing a time reproduction task in which subjects actively reproduce different temporal intervals, and a time comparison task in which subjects judge whether a test interval is longer or shorter than a reference interval. IQ, sustained and divided attention, and working memory were assessed in both groups using the Leiter International Performance Scale-Revised, and the Digit Span sub-test of the WISC-R.

Results

Children with TS-only reproduced in an overestimated fashion over-second, but not sub-second, time intervals. The precision of over-second intervals reproduction correlated with tic severity, in that the lower the tic severity, the closer the reproduction of over-second time intervals to their real duration. Time reproduction performance did not significantly correlate with IQ, attention and working memory measures in both groups. No differences between groups were documented in the time comparison task.

Conclusions

The improvement of time processing in children with TS-only seems specific for the over-second range of intervals, consistent with an enhancement in the ‘cognitively controlled’ timing system, which mainly processes longer duration intervals, and depends upon dysfunctional connectivity between the basal ganglia and the dorso-lateral prefrontal cortex. The absence of between-group differences on time comparison, moreover, suggests that TS patients manifest a selective improvement of ‘motor’ timing abilities, rather than of perceptual time abilities. Our data also support an enhancement of cognitive control processes in TS children, probably facilitated by effortful tic suppression.     

客体工作记忆任务中大脑皮层活动的记忆负荷效应

利用128导事件相关电位技术,采用延迟匹配任务的实验范式,测查了20名正常被试完成不同负荷客体任务时的皮层慢电位（slow cortical potentials,简称sp成分）,实验发现：背侧前额叶在刺激呈现后的700ms到1400ms出现记忆负荷效应,高负荷任务诱发的sp成分显著负于低负荷任务;低负荷任务诱发的sp成分在左前额区（500~1800ms）、左前额-中央区（700~1800ms）、左中央-顶叶区（1000~1400s和1800~4800ms）、右前额区（1800~4800ms）和右前额-中央区（1400~4800ms）显著负于高负荷任务,出现记忆负荷效应,但这种负荷效应在左右大脑半球所反映的心理意义可能不同     

The effect of motivation on working memory: an fMRI and SEM study

This study investigated the effective connectivity between prefrontal regions of human brain supporting motivational influence on working memory. Functional magnetic resonance imaging (fMRI) and structural equation modeling (SEM) were used to examine the interaction between the lateral orbitofrontal (OFC), medial OFC, and dorsolateral prefrontal (DLPFC) regions in the left and right hemisphere during performance of the verbal 2-back working memory task under two reinforcement conditions. The "low-motivation" condition was not associated with monetary reinforcement, while the "high-motivation" condition involved the probability of winning a certain amount of money. In the "low-motivation" condition, the OFC regions in both hemispheres positively influenced the left DLPFC activity. In the "high-motivation" condition, the connectivity in the network including the right OFC regions and left DLPFC changed from positive to negative, whereas the positive connectivity in the network composed of the left OFC and left DLPFC became slightly enhanced compared with the "low-motivation" condition. However, only the connection between the right lateral OFC and left DLPFC showed a significant condition-dependent change in the strength of influence conveyed through the pathway. This change appears to be the functional correlate of motivational influence on verbal working memory.