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。     

腹内侧前额叶在内隐认知重评中的因果作用

情绪调节对维持个体心理健康、适应社会生活十分重要, 然而以往研究主要关注外显情绪调节, 目前我们对内隐情绪调节的认知神经机制的了解还非常有限。为揭示内隐情绪调节的核心脑区, 本研究使用句子整理任务启动内隐认知重评, 并采用经颅直流电刺激(transcranial direct current stimulation, tDCS)激活内侧前额叶特别是腹内侧前额叶(ventromedial prefrontal cortex, vmPFC), 考察该脑区在内隐情绪调节中的因果作用。结果表明, vmPFC被激活的被试组(实验组, n = 40)在内隐认知重评启动条件下比tDCS伪刺激组(对照组, n = 40), 在观看负性图片时报告了更少的负性情绪, 同时负性图片诱发的晚正成分(late positive potential, LPP)波幅更低(LPP是情绪体验强度的客观指标)。同时, 实验组比对照组在观看负性图片时表现出更低的枕区P1波幅(P1为早期视觉注意程度的客观指标)。以上结果说明, 激活以vmPFC为代表的内侧前额叶不但能增强内隐情绪调节的效果, 还能减少被试对负性刺激的早期注意分配。本研究是采用tDCS技术考察启动引起的内隐情绪调节的首次尝试, 研究结果不但表明了以vmPFC为代表的内侧前额叶在内隐认知重评中的关键作用, 还为临床应用研究指出了增强内隐情绪调节能力的神经调控潜在靶点。     

情绪诱发视盲任务中的情绪注意控制机制：来自脑电ERP和时频分析的证据

采用脑电时频分析技术,对情绪诱发视盲任务中的情绪控制机制进行了分析。实验设置负性图片、中性图片及填充图片三种干扰刺激条件,关注被试正确完成目标识别时的干扰刺激加工过程。实验结果发现,负性与中性干扰刺激在注意加工阶段均较控制性的填充图片条件诱发前额中央分布的theta同步化效应,而且负性刺激所诱发的此效应又较中性情绪刺激更多分布在左侧前额和颞枕部。实验结果表明：（1）情绪诱发视盲任务下被试确实存在对于情绪干扰刺激的自上而下控制;（2）相比中性干扰刺激,负性干扰刺激在EIB中的情绪注意控制机制不仅包括前人所发现的后部颞枕区对刺激识别的注意控制,而且包括前额叶参与下的负性情绪控制。     

习得性无助是习得的吗？——对习得性无助理论及其反思的评述

Seligman和Maier（1967）在动物实验的基础上提出了著名的习得性无助理论,但在2016年,Maier和Seligman二人却联合发文对该理论进行了反思：从最新的神经生物学证据来看,习得性无助的经典理论概括存在基本错误,习得性无助并非习得而来！所谓“习得性”无助,实质上是动物对厌恶刺激长期作用的先天适应性反应,而非认知学习的结果。本文简要梳理习得性无助理论的起源与发展,深入分析这一反思的核心内容、依据及意义,对其中否定习得性无助理论概括的观点,从证据的充分性、研究范式的效度、规范概念等角度作了进行进一步的探讨,并结合新的实验范式对未来研究提出建议。     

Magnetic stimulation studies of foveal representation

The right and left visual fields each project to the contralateral cerebral hemispheres, but the extent of the functional overlap of the two hemifields along the vertical meridian is still under debate. After presenting the spatial, temporal, and functional specifications of Transcranial Magnetic Stimulation (TMS), we show that TMS is particularly suitable to study the question of foveal representation as it allows one to study the effects of selective disruption of left or right hemisphere functions on the processing of centrally presented stimuli. Future strategies for the use of TMS in further tests of visual word recognition are suggested.     

Taking control of reflexive social attention

Attention is shifted reflexively to where other people are looking. It has been argued by a number of investigators that this social attention effect reflects the obligatory bottom-up activation of domain-specific modules within the inferior temporal (IT) cortex that are specialized for processing face and gaze information. However, it is also the case that top-down factors may modulate the activation of IT cells. Here we examined behaviorally whether reflexive social orienting is purely automatic or sensitive to top-down modulation. Participants were shown an ambiguous stimulus that could be perceived either as representing EYES or a CAR. In we demonstrated between groups that an automatic shift of attention, equivalent to that triggered by a schematic FACE, occurred only when the stimulus was referred to as possessing EYES. In all participants received the EYES and CAR conditions. When the stimulus was first referred to as a CAR and then as EYES, an attentional shift was only present for the EYES condition. However, when the stimulus was first referred to as possessing EYES, and then later as a CAR, attentional shifts were observed for both conditions. These data indicate that the emergence of a reflexive social attention effect is influenced by top-down mechanisms but in an asymmetrical manner. Top-down processes appear to be effective for triggering IT involvement, that is, for perceiving a stimulus as a face, which produces the social attention effect. But top-down mechanisms are ineffective once IT involvement has been triggered. That is, once a stimulus has been seen as having eyes, it continues to be seen that way, and accordingly, the social attention effect persists.     

A few thoughts about the mind,the brain,and a child with early deprivation

Infant brain research is having an increasing impact on child psychotherapy and our understanding of the neurobiological effects of trauma and neglect. This paper outlines the 'experience-dependent' nature of brain development in infancy and the concept of critical periods in such development. The effects of deprivation on child development are illustrated and case material from a child who was institutionalized during his second year is used as a basis for posing questions about the nature of the mind and the brain. In spite of his deprivation, he was able to communicate imaginatively. Schore's proposal for the use of early interventions is put forward to counter discouragement that can be engendered by work with severely deprived children.     

Spatial working memory effects in early visual cortex

The present study investigated how spatial working memory recruits early visual cortex. Participants were required to maintain a location in working memory while changes in blood oxygen level dependent (BOLD) signals were measured during the retention interval in which no visual stimulation was present. We show working memory effects during the retention period in early visual cortex which were retinotopically organized in the sense that evoked BOLD responses were specific to the position of the remembered location on an imaginary clock. We demonstrate that this activity is similar to activity observed in conditions in which participants have to direct spatial attention to the same location. We suggest that during the retention interval modulation of neurons coding the remembered location evoke a baseline shift, providing converging evidence for the notion that spatial working memory may use spatial attention as a rehearsal mechanism.     

社会等级加工的神经基础

社会等级是社会组织的基本原则。社会地位高低的再认与面孔再认及视觉注意均表现出N200的激活, 并不同程度地共享了情感、奖赏回报、数字等级及共情特质等加工的脑区网络, 涉及额区、杏仁核、纹状体、顶内沟和前扣带回皮质等。社会等级加工与5-羟色胺递质多态性等神经递质及内分泌系统具有复杂的交互作用。未来应立足于综合研究和系统分析的视角探讨社会等级加工与神经生物学基础的作用机制并致力于服务人类生活。