认知神经科学关于表象的研究

表象是不是除命题表征之外的一种独立的表征问题一直是心理学上争论不休的话题。争论的焦点主要在视觉表象与视知觉的关系上,有些研究发现视觉表象能够激活视觉系统,甚至能够激活较早的视觉皮质(如V1区),而且视知觉的选择性障碍也会导致相应的视觉表象障碍,但另外的研究却没有发现视觉表象能够激活较早的视觉皮质,而且发现视觉表象与视知觉存在双重分离。文章最后讨论了视觉表象研究中存在的一些问题。     

The Neurodynamics of Cognition: A Tutorial on Computational Cognitive Neuroscience

Computational Cognitive Neuroscience (CCN) is a new field that lies at the intersection of computational neuroscience, machine learning, and neural network theory (i.e., connectionism). The ideal CCN model should not make any assumptions that are known to contradict the current neuroscience literature and at the same time provide good accounts of behavior and at least some neuroscience data (e.g., single-neuron activity, fMRI data). Furthermore, once set, the architecture of the CCN network and the models of each individual unit should remain fixed throughout all applications. Because of the greater weight they place on biological accuracy, CCN models differ substantially from traditional neural network models in how each individual unit is modeled, how learning is modeled, and how behavior is generated from the network. A variety of CCN solutions to these three problems are described. A real example of this approach is described, and some advantages and limitations of the CCN approach are discussed.     

The Aha! Moment: The Cognitive Neuroscience of Insight

ABSTRACT— A sudden comprehension that solves a problem, reinterprets a situation, explains a joke, or resolves an ambiguous percept is called an insight (i.e., the " Aha! moment"). Psychologists have studied insight using behavioral methods for nearly a century. Recently, the tools of cognitive neuroscience have been applied to this phenomenon. A series of studies have used electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) to study the neural correlates of the " Aha! moment" and its antecedents. Although the experience of insight is sudden and can seem disconnected from the immediately preceding thought, these studies show that insight is the culmination of a series of brain states and processes operating at different time scales. Elucidation of these precursors suggests interventional opportunities for the facilitation of insight.     

Using Neuroimaging to Measure Mental Representations: Finding Color-OpponentNeurons in Visual Cortex

To date, most neuroimaging studies have tried to localize large regions in the brain that are responsible for specific behaviors or mental operations. Psychological theory, however, is more concerned with the nature of mental functions than with the locations of their neural substrates. This article reviews work that moves beyond functional anatomy to measure how color is represented by neurons in visual cortex. The general approach has three basic steps: First, the areas under investigation are localized in the brain. Second, responses of these areas are measured to sets of systematically varying stimuli, designed to uncover the nature of cortical representations. Third, the neuroimaging data are compared with behavioral data measured with the same stimuli. Results obtained using this approach support the hypothesis that primary visual cortex contains color-opponent neurons that support perception.     

视觉特征捆绑的认知机制研究

以大学生为被试,探讨视觉特征捆绑的认知机制。实验采用空间提示范式,要求被试完成字母形状和颜色的辨别任务,考察集中注意和分散注意条件下的IC差异。结果表明,注意在视觉特征捆绑中起重要作用,集中注意能有效地减少IC的出现。同时注意对特征捆绑的调节作用表现出距离效应,即近距离比远距离的IC错误多,提示了注意的作用机制有可能与空间距离信息有关。     

功能性便秘

功能性便秘是常见的慢性便秘,罗马III提出了新的诊断标准。功能性便秘的一般治疗包括定期排便、增加活动、增加纤维素摄取,改变生活方式和调整情绪。慢传输型便秘的药物选择膨胀性泻药、渗透性泻剂、促动力剂、氯通道激活剂等。功能性排便障碍型患者可选择生物反馈治疗。治疗成功后应调节剂量,维持疗效。外科治疗应有严格的适应证。进一步研究结肠动力与排便生理,以提高对疾病的认识和提出有效的治疗。     

发展认知神经科学研究述评

发展认知神经科学是发展心理学与认知神经科学相结合而形成的跨学科研究领域,旨在从神经、行为和情境三个水平,对认知发展的方方面面进行整合性研究。本文从发展认知神经科学的研究内容、研究方法及其对发展心理学的贡献进行了梳理,并对该学科未来发展的趋势进行了展望。     

认知过程中的捆绑问题--认知神经科学的研究

捆绑问题是当前脑科学研究中的主要问题之一,近来已成为意识争论的焦点。该文结合国外对捆绑问题研究的最新成果,在概括介绍关于捆绑机制的主要理论的基础上,综述了捆绑问题与主要认知功能关系的研究,并指出不同认知过程中捆绑脑机制的精细化研究和一般性捆绑脑机制的系统化研究可能是今后这方面研究的重点。     

Toward a Cognitive Neuroscience of Metacognition

The relationship between metacognition and executive control is explored. According to an analysis by Fernandez-Duque, Baird, and Posner (this issue), metacognitive regulation involves attention, conflict resolution, error correction, inhibitory control, and emotional regulation. These aspects of metacognition are presumed to be mediated by a neural circuit involving midfrontal brain regions. An evaluation of the proposal by Fernandez-Duque et al. is made, and it is suggested that there is considerable convergence of issues associated with metacognition, executive control, working memory, and frontal lobe function. By integrating these domains and issues, significant progress could be made toward a cognitive neuroscience of metacognition.     

文本阅读认知神经科学研究进展

功能磁共振成像等认知神经科学技术被广泛引入文本阅读的认知神经活动研究以来,其成果有力地促进了文本阅读信息加工过程研究的深入发展。本文系统总结了近二十余年关于文本阅读的认知神经科学研究进展,分别介绍文本阅读的一般过程的认知神经基础和理论模型建构、文本阅读过程的推理加工、情境模型建构与转换三个主要研究领域的研究成果,并对文本阅读的认知神经研究的现状及其存在的问题进行了总结。     

发展的认知神经科学--神经科学与认知发展研究的融合点

本文介绍了发展的神经科学自 2 0世纪 80年代以来在早期突触形成、关键期及丰富环境对脑发育的影响等领域的一些突出成就 ,阐述了从神经科学与认知发展共同研究的主题来考察两个学科的整合的意义 ,并对发展的认知神经科学研究的未来趋势作了展望。     

心算加工的认知神经科学研究

近几年(1999-2005)有关心算加工的脑活动机制研究发现,类似九九乘法表这样的算术知识提取(如3×5)主要与左脑顶内沟有关,但当心算变得更复杂时(如26×38),左脑额叶下部出现明显激活,这表明心算与语言和工作记忆关系密切。另一方面,也存在不依赖于语言的即表现为视觉表象活动的心算,右脑的一些脑区在其中起了作用。简言之,所有与心算有关的脑区涉及到大脑前额皮层和颞顶枕联合皮层的综合作用,并总体表现为左脑优势,但具有特殊心算能力的人其心算还与右脑前额叶和颞叶内侧脑区的活动有关。     

The Cognitive Neuroscience of Aging and Culture

ABSTRACT— Research into the cognitive neuroscience of aging has revealed exciting and unexpected changes to the brain over the lifespan. However, studies have mostly been conducted on Western populations, raising doubts about the universality of age-related changes. Cross-cultural investigation of aging provides a window into the stability of changes with age due to neurobiology, as well as into the flexibility of aging due to life experiences that impact cognition. Behavioral findings suggest that different cultures process distinct aspects of information and employ diverse information-processing strategies. The study of aging allows us to identify those age-related neural changes that persist across cultures as well as the changes that are driven by culture-specific life experiences.     

西方认知神经科学视域下的佛教禅修

禅修与正念日益成为西方学术界认知神经科学领域的研究热点,其多数重要发现都是以重视禅修实践的佛教僧侣为研究对象。本文首先从人物传记和社会风潮两个视角,勾勒佛教如何进入科学家的研究视野,之后阐述该领域开创性的实验,最终认为二者的结合,不仅是开创了一个新的研究领域,并且将促进对人类意识的科学研究。     

负启动效应的认知神经科学研究

近几年,对负启动效应的神经机制研究发现,干扰项抑制与情节提取都是引起负启动的原因,究竟哪种机制起主要作用与实验任务有很大的关系。从现有的研究结果来看,位置负启动与前额皮层有关,EPR上表现为P1和N1波幅减小或N2波幅的增大,支持抑制机制。特性负启动P3成分仍存在不一致的结果,脑区的广泛激活模式使得研究者越来越倾向采取整合的观点。