Magnetic stimulation studies of visual cognition

The panoply of non-invasive techniques for brain imaging is responsible for much of the current excitement in cognitive neuroscience; sensory, perceptual and cognitive behaviour can now be correlated with cerebral blood flow as assessed by functional imaging, the electrical fields generated by populations of neurons or changes in magnetic fields created by electrical activity. Correlations between localized brain activity and behaviour, however, do not of themselves establish that any brain area is necessary for a particular task; necessity is the domain of the lesion technique. Transcranial magnetic stimulation (TMS) is a technique that can be used non-invasively to produce reversible functional disruption and has already been used to investigate visual detection, discrimination, attention and plasticity. The power of TMS as a `lesion' technique lies in the opportunity to combine reversible disruption with high degrees of spatial and temporal resolution. In this review we trace some of the major developments in the use of TMS as a technique for the investigation of visual cognition.     

工作记忆的认知模型与神经机制

本文评述了工作记忆认知模型的进展,阐述工作记忆神经机制研究的基本问题。研究者在工作记忆认知模型框架下,提出了工作记忆成分结构的脑模型。根据自己的研究探索,展望进一步的研究问题,以及TMS和fMRI/ERP等脑成像技术的结合运用对工作记忆认知神经科学研究的推动。     

Doing cognitive neuroscience: a third way

The “top-down” and “bottom-up” approaches have been thought to exhaust the possibilities for doing cognitive neuroscience. We argue that neither approach is likely to succeed in providing a theory that enables us to understand how cognition is achieved in biological creatures like ourselves. We consider a promising third way of doing cognitive neuroscience, what might be called the “neural dynamic systems” approach, that construes cognitive neuroscience as an autonomous explanatory endeavor, aiming to characterize in its own terms the states and processes responsible for brain-based cognition. We sketch the basic motivation for the approach, describe a particular version of the approach, so-called ‘Dynamic Causal Modeling’ (DCM), and consider a concrete example of DCM. This third way, we argue, has the potential to avoid the problems that afflict the other two approaches.     

Neurodisruption of selective attention: insights and implications

Mechanisms of selective attention are vital for coherent perception and action. Recent advances in cognitive neuroscience have yielded key insights into the relationship between neural mechanisms of attention and eye movements, and the role of frontal and parietal brain regions as sources of attentional control. Here we explore the growing contribution of reversible neurodisruption techniques, including transcranial magnetic stimulation and microelectrode stimulation, to the cognitive neuroscience of spatial attention. These approaches permit unique causal inferences concerning the relationship between neural processes and behaviour, and have revealed fundamental mechanisms of attention in the human and animal brain. We conclude by suggesting that further advances in the neuroscience of attention will be facilitated by the combination of neurodisruption techniques with established neuroimaging methods.     

The functional‐cognitive framework as a tool for accelerating progress in cognitive neuroscience: On the benefits of bridging rather than reducing levels of analyses

The subject matter of neuroscience research is complex, and synthesising the wealth of data from this research to better understand mental processes is challenging. A useful strategy, therefore, may be to distinguish explicitly between the causal effects of the environment on behaviour (i.e. functional analyses) and the mental processes that mediate these effects (i.e. cognitive analyses). In this article, we describe how the functional‐cognitive (F‐C) framework can accelerate cognitive neuroscience and also advance a functional treatment of brain activity. We first highlight that cognitive neuroscience can particularly benefit from the F‐C approach by providing an alternative to the problematic practice of reducing cognitive constructs to behavioural and/or neural proxies. Next, we outline how functional (behaviour–environment) relations can serve as a bridge between cognitive and neural processes by restoring mental constructs to their original role as heuristic tools. Finally, we give some examples of how both cognitive neuroscience and traditional functional approaches can mutually benefit from the F‐C framework.     

Mechanisms and the current state of transcranial magnetic stimulation

Transcranial magnetic stimulation (TMS) is unique among the current brain stimulation techniques because it is relatively non-invasive. TMS markedly differs from vagus nerve stimulation, deep brain stimulation and magnetic seizure therapy, all of which require either an implanted prosthesis or general anesthesia, or both. Since its rebirth in its modern form in 1985, TMS has already shown potential usefulness in at least three important domains-as a basic neuroscience research instrument, as a potential clinical diagnostic tool, and as a therapy for several different neuropsychiatric conditions. The TMS scientific literature has now expanded beyond what a single summary article can adequately cover. This review highlights several new developments in combining TMS with functional brain imaging, using TMS as a psychiatric therapy, potentially using TMS to enhance performance, and finally recent advances in the core technology of TMS. TMS' ability to non-invasively and focally stimulate the brain of an awake human is proving to be a most important development for neuroscience in general, and neuropsychiatry in particular.     

Transcranial magnetic stimulation: neurophysiological applications and safety

TMS is a non-invasive tool for measuring neural conduction and processing time, activation thresholds, facilitation and inhibition in brain cortex, and neural connections in humans. It is used to study motor, visual, somatosensory, and cognitive functions. TMS does not appear to cause long-term adverse neurological, cardiovascular, hormonal, motor, sensory, or cognitive effects in healthy subjects. Single-pulse (<1Hz) TMS is safe in normal subjects. High frequency, high-intensity repetitive TMS (rTMS) can elicit seizures even in normal subjects. Safety guidelines for using rTMS have been published.     

基于非侵入性脑刺激的认知增强：方法、伦理和应用

作为人类追求卓越的方式之一,基于非侵入性脑刺激的认知增强成为众多学科和公众关注的问题。首先阐述了非侵入性脑刺激的两种主要技术手段(经颅磁刺激和经颅直流刺激)的技术原理及其在提升健康个体认知功能上的应用,并分析了这两种技术可能带来的安全、自主选择、公平等伦理问题,最后总结了该认知增强技术在体育和军事等两个具体领域的应用。未来可进一步提高技术手段的深部脑区刺激能力及该增强技术的持续和真实效果。     

Radical embodiment: neural dynamics and consciousness

We propose a new approach to the neuroscience of consciousness, growing out of the ‘enactive’ viewpoint in cognitive science. This approach aims to map the neural substrates of consciousness at the level of large-scale, emergent and transient dynamical patterns of brain activity (rather than at the level of particular circuits or classes of neurons), and it suggests that the processes crucial for consciousness cut across the brain–body–world divisions, rather than being brain-bound neural events. Whereas standard approaches to the neural correlates of consciousness have assumed a one-way causal-explanatory relationship between internal neural representational systems and the contents of consciousness, our approach allows for theories and hypotheses about the two-way or reciprocal relationship between embodied conscious states and local neuronal activity.     

Hemispheric asymmetry reduction in older adults: the HAROLD model

A model of the effects of aging on brain activity during cognitive performance is introduced. The model is called HAROLD (hemispheric asymmetry reduction in older adults), and it states that, under similar circumstances, prefrontal activity during cognitive performances tends to be less lateralized in older adults than in younger adults. The model is supported by functional neuroimaging and other evidence in the domains of episodic memory, semantic memory, working memory, perception, and inhibitory control. Age-related hemispheric asymmetry reductions may have a compensatory function or they may reflect a dedifferentiation process. They may have a cognitive or neural origin, and they may reflect regional or network mechanisms. The HAROLD model is a cognitive neuroscience model that integrates ideas and findings from psychology and neuroscience of aging.     

Introducing Transcranial Magnetic Stimulation (TMS) and its Property of Causal Inference in Investigating Brain-Function Relationships

Transcranial magnetic stimulation (TMS) is a method capable of transiently modulating neural excitability. Depending on the stimulation parameters information processing in the brain can be either enhanced or disrupted. This way the contribution of different brain areas involved in mental processes can be studied, allowing a functional decomposition of cognitive behavior both in the temporal and spatial domain, hence providing a functional resolution of brain/mind processes. The aim of the present paper is to argue that TMS with its ability to draw causal inferences on function and its neural representations is a valuable neurophysiological tool for investigating the causal basis of neuronal functions and can provide substantive insight into the modern interdisciplinary and (anti)reductionist neurophilosophical debates concerning the relationships between brain functions and mental abilities. Thus, TMS can serve as a heuristic method for resolving causal issues in an arena where only correlative tools have traditionally been available.     

Cognitive neuroscience in China

In the last decade, cognitive neuroscience in China has advanced in at least four aspects: first, specialized research institutes and bodies have been set up throughout the nation; second, more and more high‐tech research facilities and approaches have been adopted by domestic researchers; third, international conferences on cognitive neuroscience have been held in Mainland China; and finally, publications relating cognitive processes to neural activation and functioning have increased. This paper selectively reviews research on perception and face recognition, attention, language, memory, and disorders in cognitive brain functions carried out by scientists in Mainland China. For visual perception, some excellent work has been carried out to investigate the neural mechanisms of perceptual priming, perceptual grouping, and perception of global/local properties in compound stimuli. For attention, much work is on issues such as the time course of brain activation in selective attention, the patterns of event‐related potentials in visual and auditory selective attention, and the effect of pre‐cueing on spatial attention. Because the Chinese language has many unique characteristics in phonological and syntactic systems and in the writing system, much research carried out in China takes advantage of these characteristics, trying to separate the universal and language‐specific aspects of language processing and their neural correlates. Memory research is mainly at neuropsychological and neurobiological levels. Disorders of cognitive functioning and their underlying impairments in the brain are attracting more and more attention. The paper concludes that as the Chinese economy is growing fast, more resources will be poured into basic research. Thus, systematic research in various fields of cognitive neuroscience by Chinese scientists is no longer a dream. It is reasonable to expect that research in this field will be accelerated in China and become an important force in the world in the near future.     

脑的感知觉无意识加工及其研究进展

该文从无意识加工与认知、脑结构,神经网络的关系等三个层面,阐述了近年来认知神经科学在无意识研究方面的进展。主要就无意识与意识的相互转化、无意识加工与认知层次、脑结构之间的关联性、突触的联结方式等问题进行了讨论,并对认知神经科学如何研究无意识与意识问题提出展望,     

特征捆绑机制的理论模型

捆绑问题被认为是认知科学和神经科学的中心问题之一,对心理过程的认知神经机制研究起到了重要推动作用。特征捆绑机制研究有认知和神经科学两大范式。特征整合论在认知理论中最具代表性,形式理论修正了其在错觉性结合测量等方面的不足,双阶段理论突出了前注意捆绑。时间同步性理论是影响最大的捆绑理论,神经网络模型为捆绑机制提出了更具体的结构模型。两大范式的整合及由低级认知过程向高级心理过程的深化可能是今后捆绑机制研究的重点     

群体面孔情绪感知的神经机制

如何揭示情绪性面孔加工的认知神经机制一直是心理学和社会神经科学的热点课题。以往研究主要采用单独面孔表情作为情绪诱发或呈现方式, 但对群体情绪知觉与体验的关注极其缺乏, 而群体面孔表情作为群体情绪的主要表达方式, 亟待深入关注。因此, 本项目将采用群体面孔(面孔群)表情作为群体情绪刺激, 拟通过事件相关电位(ERP)、核磁共振(fMRI)以及经颅磁刺激(TMS)等技术结合行为研究, 尝试从情绪信息(效价和强度)、朝向信息(正面、侧面、倒置)、完整性(局部呈现、完整呈现)、空间频率信息(完整、高频、低频)等方面探明群体面孔表情加工的时间动态特征和大脑激活模式。这将有助于全面认识和深入了解群体情绪识别的一般规律, 对于更好地优化社会互动也具有现实意义。     

The emergence of social cognitive neuroscience

Social cognitive neuroscience is an emerging interdisciplinary field of research that seeks to understand phenomena in terms of interactions between 3 levels of analysis: the social level, which is concerned with the motivational and social factors that influence behavior and experience; the cognitive level, which is concerned with the information-processing mechanisms that give rise to social-level phenomena; and the neural level, which is concerned with the brain mechanisms that instantiate cognitive-level processes. The social cognitive neuroscience approach entails conducting studies and constructing theories that make reference to all 3 levels and contrasts with traditional social psychological and cognitive neuroscientific research that primarily makes reference to 2 levels. The authors present an introduction to and analysis of the field by reviewing current research and providing guidelines and suggested directions for future work.     

背外侧前额叶对主动遗忘负性社会反馈的作用：针对抑郁症的TMS研究

抑郁症患者的负性心境可能源于其抑制功能障碍。患者在主动遗忘负性材料时无法有效调用背外侧前额叶(the dorsolateral prefrontal cortex, DLPFC)等负责抑制控制的额叶脑网络。同时, 患者对社会信息的加工比对非社会信息的加工存在更明显的认知神经障碍, 很难主动遗忘对自己不利的社会反馈信息。为了提高抑郁症患者对负性社会反馈的主动遗忘能力, 本研究采用经颅磁刺激技术(transcranial magnetic stimulation, TMS), 考察抑郁症患者在左侧(n = 32)或右侧DLPFC (n = 30)被激活后其记忆控制能力的改变。结果表明, 当患者的DLPFC被TMS激活时, 他们对社会拒绝的回忆正确率与健康对照组(n = 31)无差异, 且TMS激活右侧DLPFC还改善了患者对他人的社会态度。本研究是采用TMS提高抑郁症患者主动遗忘能力的首次尝试, 研究结果不但支持了DLPFC与记忆控制功能的因果关系, 还为临床治疗抑郁症、创伤后应激障碍、药物成瘾等患者的记忆控制缺陷提供了明确的神经靶点。     

Cortical coordination dynamics and cognition

New imaging techniques in cognitive neuroscience have produced a deluge of information correlating cognitive and neural phenomena. Yet our understanding of the inter-relationship between brain and mind remains hampered by the lack of a theoretical language for expressing cognitive functions in neural terms. We propose an approach to understanding operational laws in cognition based on principles of coordination dynamics that are derived from a simple and experimentally verified theoretical model. When applied to the dynamical properties of cortical areas and their coordination, these principles support a mechanism of adaptive inter-area pattern constraint that we postulate underlies cognitive operations generally.     

简评认知神经科学取向的智力观

随着认知神经科学与生物技术的发展,现当代智力理论的构建明显地受到其影响。这些智力理论被称之为认知神经科学取向的智力观,如Garlick的神经可塑性模型;Das等人根据Luria的神经模型提出的智力PASS模型;Kaufman提出的儿童评估成套测验（K-ABC）;Ceci的生物-生态学智力模型及Perkins的真智力理论等。这些智力观都直接将认知神经过程或神经生物学的某些研究成果融合于其理论模型之中。认知神经科学取向的智力观为智力研究提供了新的研究视角和思考维度,但同时也可能面临某种发展困境。第二代认知科学的具身认知思想可能是解决传统身-心争论的有效途径。     

评述早期儿童认知发展的神经科学研究

神经科学的迅猛发展,尤其是神经科学新的研究手段的广泛运用,使得神经科学在儿童早期认知发展的神经机制研究中取得了长足的进展。本文主要涉及神经发育中神经系统的可塑性、关键期,以及知觉、注意、记忆和空间认知等认知发展诸多方面的神经机制。