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1.
近二十年,使用认知神经科学手段探讨情绪调节成为了研究的热点。晚期正成分(Late Positive Potential,LPP)是情绪调节脑电研究中的一个典型成分,在不同的时间窗中分析LPP的波幅的变化及其优势激活脑区的迁移能够反映情绪调节加工过程中个体由对情绪刺激的感知到相应的认知调控过程的转变。LPP的时间-空间迁移模式被应用于情绪调节的发展研究,揭示从童年到青少年再到成年期个体情绪的潜在神经机制。研究者关注幼儿期、童年期、青少期、成人期个体在情绪调节加工过程中LPP波幅的变化及其时间-空间迁移模式特征,把不同年龄段个体情绪调节的发展特点与其大脑关键脑区(主要是前额叶)发育状况进行联系,为儿童身体发育和心理发展的主题提供更多的证据支持。未来的研究应加强对LPP在异常发展研究中应用,关注大脑发育与激素变化对LPP变化的影响,并加强对LPP调节效应的个体差异等问题的探讨。  相似文献   

2.
The brain stores information in an associative manner so that contextually related entities are connected in memory. Such associative representations mediate the brain’s ability to generate predictions about which other objects and events to expect in a given context. Likewise, the brain encodes and is able to rapidly retrieve the affective value of stimuli in our environment. That both contextual associations and affect serve as building blocks of numerous mental functions often makes interpretation of brain activation ambiguous. A critical brain region where such activation has often resulted in equivocal interpretation is the medial orbitofrontal cortex (mOFC), which has been implicated separately in both affective and associative processing. To characterize its role more unequivocally, we tested whether activity in the mOFC was most directly attributable to affective processing, associative processing, or a combination of both. Subjects performed an object recognition task while undergoing fMRI scans. Objects varied independently in their affective valence and in their degree of association with other objects (associativity). Analyses revealed an overlapping sensitivity whereby the left mOFC responded both to increasingly positive affective value and to stronger associativity. These two properties individually accounted for mOFC response, even after controlling for their interrelationship. The role of the mOFC is either general enough to encompass associations that link stimuli both with reinforcing outcomes and with other stimuli or abstract enough to use both valence and associativity in conjunction to inform downstream processes related to perception and action. These results may further point to a fundamental relationship between associativity and positive affect.  相似文献   

3.
mRNA translation, or protein synthesis, is a major component of the transformation of the genetic code into any cellular activity. This complicated, multistep process is divided into three phases: initiation, elongation, and termination. Initiation is the step at which the ribosome is recruited to the mRNA, and is regarded as the major rate-limiting step in translation, while elongation consists of the elongation of the polypeptide chain; both steps are frequent targets for regulation, which is defined as a change in the rate of translation of an mRNA per unit time. In the normal brain, control of translation is a key mechanism for regulation of memory and synaptic plasticity consolidation, i.e., the off-line processing of acquired information. These regulation processes may differ between different brain structures or neuronal populations. Moreover, dysregulation of translation leads to pathological brain function such as memory impairment. Both normal and abnormal function of the translation machinery is believed to lead to translational up-regulation or down-regulation of a subset of mRNAs. However, the identification of these newly synthesized proteins and determination of the rates of protein synthesis or degradation taking place in different neuronal types and compartments at different time points in the brain demand new proteomic methods and system biology approaches. Here, we discuss in detail the relationship between translation regulation and memory or synaptic plasticity consolidation while focusing on a model of cortical-dependent taste learning task and hippocampal-dependent plasticity. In addition, we describe a novel systems biology perspective to better describe consolidation.  相似文献   

4.
The bilingual brain: cerebral representation of languages.   总被引:4,自引:0,他引:4  
The present article deals with theoretical and experimental aspects of language representation in the multilingual brain. Two general approaches were adopted in the study of the bilingual brain. The study of bilingual aphasics allows us to describe dissociations and double dissociations between the different subcomponents of the various languages. Furthermore, symptoms peculiar to bilingual aphasia were reported (pathological mixing and switching and translations disorders) which allowed the correlation of some abilities specific to bilinguals with particular neurofunctional systems. Another approach to the study of the bilingual brain is of the experimental type, such as electrophysiological investigations (electrocorticostimulation during brain surgery and event-related potentials) and functional neuroanatomy studies (positron emission tomography and functional magnetic resonance imaging). Functional neuroanatomy studies investigated the brain representation of languages when processing lexical and syntactic stimuli and short stories. Neurophysiologic and neuroimaging studies evidenced a similar cerebral representation of L1 and L2 lexicons both in early and late bilinguals. The representation of grammatical aspects of languages seems to be different between the two languages if L2 is acquired after the age of 7, with automatic processes and correctness being lower than those of the native language. These results are in line with a greater representation of the two lexicons in the declarative memory systems, whereas morphosyntactic aspects may be organized in different systems according to the acquisition vs learning modality.  相似文献   

5.
It has been suggested that neural systems for lexical processing of nouns and verbs are anatomically distinct. The aim of the present study was to investigate if brain asymmetry for the processing of these two grammatical classes is also different. Neurologically intact adults performed a lateralized lexical decision task with grammatically unambiguous words of high, medium, and low degrees of imagery. For error scores a right visual field (RVF) advantage and an overall effect of imageability were obtained. For latency scores grammatical class and imageability modified visual field differences: in the noun class a RVF advantage was obtained only for low imagery nouns, while for the verbs the RVF advantage was present for both medium and low imagery verbs. These results suggest that the participation of right hemisphere neural systems in the processing of verbs is more limited than in the processing of nouns.  相似文献   

6.
内隐自尊与外显自尊的关系:多重内隐测量的视角   总被引:4,自引:2,他引:2  
杨福义  梁宁建 《心理科学》2007,30(4):785-790
本研究以102名大学生为被试,从多重内隐测量的视角出发,运用内隐联想测验(IAT)、Go/No-go联想任务(GNAT)和外部情绪性Simon任务(EAST)三种实验程序对内隐自尊及其特性进行了测量和研究,同时运用结构方程建模对内隐自尊和外显自尊的结构关系进行了探讨。结果表明:(1)IAT、GNAT和EASI这三种基于反应时范式的内隐自尊测量方法是有效的,均能有效检测出内隐自尊效应,内隐自尊的特性表现为个体倾向于将自我与积极属性或事物相联,将他人与消极属性或事物相联;(2)内隐自尊与外显自尊是分离的结构,两者是相对独立的两个自我评价系统,支持内隐自尊和外显自尊的两维结构说;(3)双重态度模型和信息加工双过程模型两种理论模型都可以解释内隐自尊和外显自尊的分离现象。  相似文献   

7.
The problem of how word meaning is processed in the brain has been a topic of intense investigation in cognitive neuroscience. While considerable correlational evidence exists for the involvement of sensory-motor systems in conceptual processing, it is still unclear whether they play a causal role. We investigated this issue by comparing the performance of patients with Parkinson’s disease (PD) with that of age-matched controls when processing action and abstract verbs. To examine the effects of task demands, we used tasks in which semantic demands were either implicit (lexical decision and priming) or explicit (semantic similarity judgment). In both tasks, PD patients’ performance was selectively impaired for action verbs (relative to controls), indicating that the motor system plays a more central role in the processing of action verbs than in the processing of abstract verbs. These results argue for a causal role of sensory-motor systems in semantic processing.  相似文献   

8.
The P600 as an indicator of syntactic ambiguity   总被引:5,自引:0,他引:5  
In a study using event-related brain potentials, we show that the current characterization of the P600 component as an indicator of revision processes (reanalysis and repair) in sentence comprehension must be extended to include the recognition of syntactic ambiguity. By comparing the processing of ambiguous and unambiguous sentence constituents in German, we show that the P600 is elicited when our language processing system has syntactic alternatives at a certain item given in the input string. That the P600 is sensitive to syntactic ambiguity adds crucial evidence to current debates in psycholinguistic modelling, as the results clearly favour parallel models of syntactic processing which assume that ambiguity is recognized and costly.  相似文献   

9.
Previous research has demonstrated that the degree of aesthetic pleasure a person experiences correlates with the activation of reward functions in the brain. However, it is unclear whether different affective qualities and the perceptions of beauty that they evoke correspond to specific areas of brain activation. Major and minor musical keys induce two types of affective qualities--bright/happy and dark/sad--that both evoke aesthetic pleasure. In the present study, we used positron emission tomography to demonstrate that the two musical keys (major and minor) activate distinct brain areas. Minor consonant chords perceived as beautiful strongly activated the right striatum, which has been assumed to play an important role in reward and emotion processing, whereas major consonant chords perceived as beautiful induced significant activity in the left middle temporal gyrus, which is believed to be related to coherent and orderly information processing. These results suggest that major and minor keys, both of which are perceived as beautiful, are processed differently in the brain.  相似文献   

10.
The visual system historically has been defined as consisting of at least two broad subsystems subserving object and spatial vision. These visual processing streams have been organized both structurally as two distinct pathways in the brain, and functionally for the types of tasks that they mediate. The classic definition by Ungerleider and Mishkin labeled a ventral "what" stream to process object information and a dorsal "where" stream to process spatial information. More recently, Goodale and Milner redefined the two visual systems with a focus on the different ways in which visual information is transformed for different goals. They relabeled the dorsal stream as a "how" system for transforming visual information using an egocentric frame of reference in preparation for direct action. This paper reviews recent research from psychophysics, neurophysiology, neuropsychology and neuroimaging to define the roles of the ventral and dorsal visual processing streams. We discuss a possible solution that allows for both "where" and "how" systems that are functionally and structurally organized within the posterior parietal lobe.  相似文献   

11.
《Cognitive development》2002,17(3-4):1407-1428
In this article, I highlight the discipline of developmental psychopathology as an integrative framework that builds upon the historical underpinnings of a constructivist perspective. After presenting illustrative developmental psychopathology principles that I consider to be central to a constructivist view, I turn my attention to the role of experience on brain development. This serves as the entree into a discussion of research conducted with maltreated children on brain event-related potentials (ERPs) and the cognitive processing of emotional stimuli, neuroendocrine functioning, and acoustic startle. Each of these components of brain functioning serve to underscore how different neurobiological systems reflect the way in which individuals ascribe meaning to traumatic experiences. Research on child maltreatment, an “experiment of nature,” reveals that maltreated children actively construct their reality at both the biological and psychological levels of analysis, at least in part based on the meaning these children impute to their caregiving experiences.  相似文献   

12.
Ordinality is – beyond numerical magnitude (i.e., quantity) – an important characteristic of the number system. There is converging empirical evidence that (intra)parietal brain regions mediate number magnitude processing. Furthermore, recent findings suggest that the human intraparietal sulcus (IPS) supports magnitude and ordinality in a domain-general way. However, the latter findings are derived from adult studies and with respect to children (i.e., developing brain systems) both the neural correlates of ordinality processing and the precise role of the IPS (domain-general vs. domain-specific) in ordinality processing are thus far unknown. The present study aims at filling this gap by employing functional magnetic resonance imaging (fMRI) to investigate numerical and non-numerical ordinality knowledge in children with and without developmental dyscalculia. In children (without DD) processing of numerical and non-numerical ordinality alike is supported by (intra)parietal cortex, thus extending the notion of a domain-general (intra)parietal cortex to developing brain systems. Moreover, activation extents in response to numerical ordinality processing differ significantly between children with and without dyscalculia in inferior parietal regions (supramarginal gyrus and IPS).  相似文献   

13.
14.
Recent research suggests that emotion effects in word processing resemble those in other stimulus domains such as pictures or faces. The present study aims to provide more direct evidence for this notion by comparing emotion effects in word and face processing in a within-subject design. Event-related brain potentials (ERPs) were recorded as participants made decisions on the lexicality of emotionally positive, negative, and neutral German verbs or pseudowords, and on the integrity of intact happy, angry, and neutral faces or slightly distorted faces. Relative to neutral and negative stimuli both positive verbs and happy faces elicited posterior ERP negativities that were indistinguishable in scalp distribution and resembled the early posterior negativities reported by others. Importantly, these ERP modulations appeared at very different latencies. Therefore, it appears that similar brain systems reflect the decoding of both biological and symbolic emotional signals of positive valence, differing mainly in the speed of meaning access, which is more direct and faster for facial expressions than for words.  相似文献   

15.
本研究试图探究背景应激对应激相关大脑自发神经活动的影响。使用日常应激水平作为背景应激的量化指标,同时,使用静息态fMRI技术采集了个体在静息态下的大脑自发神经活动,并使用局部一致性(ReHo)作为指标。结果发现,背景应激越高的个体,右侧海马(扩展到丘脑和脑干)静息态下局部一致性水平越高。结果提示,经历了高背景应激的个体会表现出边缘系统脑区自发神经活动的持续活跃状态。  相似文献   

16.
躯体和面孔是个体情绪表达与识别的重要线索。与面部表情相比,躯体表情加工的显著特点是补偿情绪信息,感知运动与行为信息,及产生适应性行为。情绪躯体与面孔加工的神经基础可能相邻或部分重合,但也存在分离;EBA、FBA、SPL、IPL等是与躯体表情加工相关的特异性脑区。今后应系统研究面孔、躯体及语音情绪线索加工潜在的神经基础,探讨躯体情绪加工的跨文化差异,考察情绪障碍患者的躯体表情加工特点。  相似文献   

17.
Toward a theory of visual consciousness.   总被引:3,自引:0,他引:3  
The visual brain consists of several parallel, functionally specialized processing systems, each having several stages (nodes) which terminate their tasks at different times; consequently, simultaneously presented attributes are perceived at the same time if processed at the same node and at different times if processed by different nodes. Clinical evidence shows that these processing systems can act fairly autonomously. Damage restricted to one system compromises specifically the perception of the attribute that that system is specialized for; damage to a given node of a processing system that leaves earlier nodes intact results in a degraded perceptual capacity for the relevant attribute, which is directly related to the physiological capacities of the cells left intact by the damage. By contrast, a system that is spared when all others are damaged can function more or less normally. Moreover, internally created visual percepts-illusions, afterimages, imagery, and hallucinations-activate specifically the nodes specialized for the attribute perceived. Finally, anatomical evidence shows that there is no final integrator station in the brain, one which receives input from all visual areas; instead, each node has multiple outputs and no node is recipient only. Taken together, the above evidence leads us to propose that each node of a processing-perceptual system creates its own microconsciousness. We propose that, if any binding occurs to give us our integrated image of the visual world, it must be a binding between microconsciousnesses generated at different nodes. Since any two microconsciousnesses generated at any two nodes can be bound together, perceptual integration is not hierarchical, but parallel and postconscious. By contrast, the neural machinery conferring properties on those cells whose activity has a conscious correlate is hierarchical, and we refer to it as generative binding, to distinguish it from the binding that might occur between the microconsciousnesses.  相似文献   

18.
Several models of person perception predict that expectancy violations have both affective and cognitive consequences for the perceiver. Although extant evidence generally supports these claims, the temporal resolution of traditional self-report measures has limited researchers' ability to convincingly link underlying physiological processes with observed outcomes. In this study, we examined these issues by measuring brain (event-related brain potentials) and peripheral (facial electromyogram) electrophysiological activity while participants read positive and negative expectancy-consistent, expectancy-violating, expectancy-irrelevant, and semantically incongruent behavioral sentences about fictitious characters. The electromyogram results indicated that negative (but not positive) expectancy-violating behaviors elicited enhanced negative affect as early as 100 to 300 ms poststimulus. The event-related potentials showed enhanced positivities with latency exceeding 300 ms in response to expectancy violations and negative behaviors. Semantically incongruent sentence endings influenced a separate negative component (N400), suggesting fundamental differences between semantic- and behavior-consistency processing. This difference also was evident in participants' recall. Implications for theoretical models of expectancy violation are discussed.  相似文献   

19.
Recent studies suggest that cross-frequency coupling (CFC) might play a functional role in neuronal computation, communication and learning. In particular, the strength of phase-amplitude CFC differs across brain areas in a task-relevant manner, changes quickly in response to sensory, motor and cognitive events, and correlates with performance in learning tasks. Importantly, whereas high-frequency brain activity reflects local domains of cortical processing, low-frequency brain rhythms are dynamically entrained across distributed brain regions by both external sensory input and internal cognitive events. CFC might thus serve as a mechanism to transfer information from large-scale brain networks operating at behavioral timescales to the fast, local cortical processing required for effective computation and synaptic modification, thus integrating functional systems across multiple spatiotemporal scales.  相似文献   

20.
The evolution of biological (intermediary) complexity strongly depends upon the information‐processing advantages it confers to cells and organisms. As a matter of fact, highly complex biological structures such as the cellular signaling system and the vertebrate nervous system have been evolved in order to inform the living system about its surround, subsequently orienting the internal, productive activities. The evolutionary success of these types of informational structures ("infostructures") exemplifies that, almost universally, the “bit” may act as a successful substitute for the “joule”. Recent molecular biology research on cellular signaling systems has disclosed their amazing information‐processing sophistication and the crucial role they play in the formation and functioning of the vertebrate brain. In the neurosciences, duality theory has highlighted the way in which the cortical maps and the cerebral substructures of the vertebrate brain are “topologically” integrated in order to perform an adaptive information‐processing. The development of comprehensive conceptualizations relating brain processing and intracellular processing may well be a strategic step in the development of a vertical “information science”.  相似文献   

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