首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 171 毫秒
1.
人类的时间知觉会受到情绪的调节发生主观扭曲,这种调节可以通过情绪的体验与预期来实现.本文区分了体验性情绪和预期性情绪调节时间知觉的作用方式和认知机制,基于标量计时理论,提出了在不同加工阶段情绪调节时间知觉的认知理论模型,并梳理了情绪调节时间知觉的神经生理学基础和脑机制方面的证据.未来研究需更关注预期性情绪对时间知觉的调节作用,考察注意、唤醒和效价等因素的交互影响,并进一步探究情绪调节时间知觉的神经机制.  相似文献   

2.
视觉加工的核心是对视觉场景中与认知行为相关的客体进行区分与识别。自然情境下的视觉输入往往由极为复杂的三维场景信息组成,包含多个视觉客体。一般认为,视觉轮廓信息是对视觉图像进行划分,识别客体的重要依据。为此,视觉科学家们对视觉轮廓加工的认知神经机制进行了大量的研究与探索。然而,这些研究往往仅仅集中于轮廓加工的某一方面或特定阶段,迄今尚未有学者针对关于轮廓加工的研究结果进行系统性的总结。我们提出,视觉轮廓加工共包括轮廓检测、轮廓从属判断、轮廓整合三个相互作用的关键性阶段,并在综合现有电生理、人类脑成像及脑电研究证据的基础上,分别对这三个阶段对应的神经生理特性、加工机理与信息交互机制进行探讨。最后,我们列举了进一步研究轮廓加工认知神经机制所面临的主要挑战。  相似文献   

3.
A型肉毒毒素(简称肉毒素)可引起可逆的局部肌肉麻痹,注射于特定面部肌肉可影响个体的情绪体验,还会干扰个体对情绪性材料(面部表情、语言文字和视频)中情绪信息的加工。认知神经科学研究发现,注射肉毒素会影响杏仁核的激活,影响奖赏系统的功能,以及其他大脑皮层的认知神经功能。面部反馈假说和社会反馈假说分别从个体与社会层面对肉毒素的作用加以解释:注射肉毒素使被注射者的肌肉反馈减少,弱化相应情绪的体验和加工;人际交往中,面部模仿使观察者的情绪体验与被注射者趋同,反过来同样影响被注射者的情绪体验。基于已有研究,本文提出面部反馈与社会反馈的整合模型对注射肉毒素影响情绪加工的认知神经机制进行系统阐释。未来研究可拓展相关的研究范式和方法,关注肉毒素注射对不同层面和水平的情绪加工的影响,及其相应的认知神经机制,进一步明确面部反馈与社会反馈的相互作用,并且考察肉毒素用于抑郁症等心理疾病治疗的作用机制。  相似文献   

4.
暗示性运动是指个体观看静止图片时从中知觉到的运动.研究者采用高低认知水平两类暗示性运动刺激材料,借助"冻结帧"、直接观看、运动后效和f MRI适应等任务范式,探讨了注意和意识在暗示性运动加工中的作用及其记忆特点;并借助脑成像等技术,考察了颞中区、颞上皮层区、颞上沟、镜像神经元系统等脑区在暗示性运动加工中的作用.但由于暗示性运动加工涉及"视觉腹侧通路与背侧通路功能的分离与整合"问题,目前对相关研究结果和解释还存在争议,暗示性运动加工的认知神经机制仍有待于进一步研究.  相似文献   

5.
语音是人类交流的主要方式,语音理解也是人脑特有的核心认知功能。人脑中的动态神经活动如何编码连续语音流的声学特征,并解析出多个层级的语言结构是认知神经科学领域的重要问题。近年来,一系列脑电图、脑磁图研究通过包络跟踪响应、层级跟踪响应等新指标来刻画连续语音的神经加工机制。本文对这些研究进行综述,并聚焦于对两个语音加工问题:一是大脑如何编码语音中连续变化的声学特征。这方面的研究表明,大脑中的低频神经活动可以动态跟踪语音包络并且受到高级认知功能调节。二是大脑如何表征语音中不同大小的语言单元,比如音节、词、短语、语句。研究显示,大脑皮层中不同时间尺度的神经活动分别跟踪不同大小的语言单元,构成对多层级语言单元的并行表征。综合上述,近期研究初步揭示了大脑如何表征连续语音的声学特征并构建不同层次的语言单元,为进一步研究大脑如何加工连续语音提供了新的思路。  相似文献   

6.
社会神经科学是研究人类的社会行为及其神经机制的综合性学科.从1992年学科成立至今,社会神经科学研究取得了丰硕的成果.本文系统介绍了该领域4个主要研究方向:社会知觉、社会认知、社会调节和社会互动的研究成果,并在此基础上总结了各研究方向的核心问题,即社会知觉加工的模块化问题、人类社会认知的独特性问题和社会调节加工的跨文化一致性问题.已有研究表明,社会知觉加工至少在计算算法层面是特异化的;心智化系统是人类独有的加工模块;人类社会调节不具备跨文化的一致性;大脑间耦合可能是社会互动共有的神经机制.最后,展望了社会神经科学未来的发展方向.  相似文献   

7.
多方式认知功能成像研究进展   总被引:4,自引:1,他引:4  
对大脑结构和功能的深入研究要求认知功能成像技术同时具有高时间分辨率和高空间分辨率.多方式认知功能成像通过不同成像技术fMRI/PET和EEG/MEG的结合,能够同时在空间定位和时间过程上研究大脑认知活动的动态过程.多方式认知功能成像已经被成功地应用于选择性注意、视觉通路、随意运动和语义加工等的研究,并揭示了相关大脑活动的空间和时间特征.今后的研究将进一步提高多方式认知功能成像的时空分辨率和准确性,以更深入地探索认知功能的神经机制.  相似文献   

8.
目的:探讨卒中后失语患者高级语言认知功能的改变。方法:利用事件相关电位N400探讨15例脑卒中后失语患者(观察组)及15例正常人(对照组)图片-词语(名词和动词)语义一致(匹配)与语义不一致(不匹配)时的语言加工过程。结果:与对照组相比脑卒中后失语患者N400潜伏期有统计学差异。结论:卒中后失语患者存在语言加工过程的延迟,额叶以及顶叶可能在名词及动词早期的语义生成的过程中起重要作用。  相似文献   

9.
如何减少注意资源的消耗、提升人类在动态视觉持续性注意任务中的表现,是持续性注意研究关注的重点问题,具有理论和实践的重要意义。多目标追踪任务是研究个体持续性注意的常用实验室方法。多目标追踪任务中,观察者可以利用基于物体特征的分组效应将多个运动目标知觉为一个更大的运动单元,从而减少注意资源的消耗、提高追踪任务表现。为了进一步节省注意资源、提升注意追踪的表现,研究者提出了注意追踪中分组效应的可加性问题。分组效应的可加性表现为基于两个及以上特征的分组对追踪表现的提高优于基于一个特征的分组。可加性的研究对理解不同分组效应的认知机制,个体动态视觉追踪中的注意机制和注意资源分配等具有重要意义。本文对以往的行为以及神经影像学研究进行了汇总,讨论了不同类型分组效应的知觉加工机制及其可加性,系统阐述了基于不同表面特征的不可加性,和基于表面特征与特定时空特征可加性的认知及其神经基础。未来可以从行为学实验角度探究更多基于不同特征分组效应的可加性,或者从注意追踪中基于不同分组效应的神经机制入手,探讨分组效应的可加性问题,为分组效应的分类及可加性研究提供更多认知和神经层面的依据。  相似文献   

10.
音乐是一种听觉艺术形式,在儿童教育和发展中,尤其是语言能力发展中扮演着重要角色。语音意识是个体感知识别、分析和运用语音的能力,是预测儿童语言读写能力的重要指标。本文梳理了近十年来音乐训练影响儿童语音意识的研究证据,并讨论了音乐训练可能促进语音意识的神经基础和解释模型。大量研究表明,音乐训练可以在行为水平提高儿童在语音意识测量任务上的成绩。此外,音乐训练从两方面影响语音加工的神经基础:一方面通过影响皮层下基本听觉神经通路与大脑听觉皮层,促进儿童前注意水平的语音感知能力;另一方面通过影响语音加工大脑区域间的功能连接,促进语音编码,强化语音加工的听觉-运动整合功能。相关神经机制为音乐训练促进儿童的语音意识提供了生物学基础。基于已有研究,本文提出综合的层级模型对音乐训练影响儿童语音意识的认知神经机制进行系统的解释,该模型认为音乐训练影响语音意识的认知神经机制分为3个层级:第一层级,音乐训练通过影响基本听觉神经通路促进了语音的基本听觉加工,其中节奏训练促进对语音时长信息的感知,音高训练促进对语音频率信息的感知;第二层级,音乐训练通过影响语音加工的神经网络,进一步促进语音编码,其中节奏训练主要促进...  相似文献   

11.
The results of the multivariate analysis of variance confirmed statistically significant differences in latency and amplitude of some ERPs waves to nouns and ERPs to verbs. ERPs to nouns differ from ERPs to verbs by a significantly longer latency and greater amplitude of some waves. A comparison of the characteristics of ERPs to nouns and ERPs to verbs separately in males and females produced basically identical results; in females, however, there are much fewer significant differences than in males. Interaction between the site of the recording electrode and features of ERPs to words of different word classes however could not be demonstrated.  相似文献   

12.
Word formation in Arabic has traditionally been assumed to involve interdigitation of a consonantal root with a vocalic pattern. This view is adopted by a large number of modern generative morphologists. More recently, however, several morphologists have argued that words in Semitic are formed from fully vocalised stems. In this paper, I argue that in San'ani (the dialect of San'a), and in some other Arabic dialects, there is a class of verbs that have as part of either their denotations or connotations a diminutive sense. I then consider diminutive nouns in the dialect. On the basis of semantic and phonological relationships between diminutive verbs and their non-diminutive counterparts, as well as native speakers' explanations of certain diminutive verbs, and the relationship between diminutive nouns and their non-diminutive counterparts, I argue that while some derivational processes take the root as the basic morphological unit, phonological and semantic similarities between certain stems can only be accounted for by derivation from a fully vocalised stem. I therefore conclude that both root-based and stem-based types of word formation occur.  相似文献   

13.
In sentence comprehension research, the case system, which is one of the subsystems of the language processing system, has been assumed to play a crucial role in signifying relationships in sentences between noun phrases (NPs) and other elements, such as verbs, prepositions, nouns, and tense. However, so far, less attention has been paid to the question of how cases are processed in our brain. To this end, the current study used fMRI and scanned the brain activity of 15 native English speakers during an English-case processing task. The results showed that, while the processing of all cases activates the left inferior frontal gyrus and posterior part of the middle temporal gyrus, genitive case processing activates these two regions more than nominative and accusative case processing. Since the effect of the difference in behavioral performance among these three cases is excluded from brain activation data, the observed different brain activations would be due to the different processing patterns among the cases, indicating that cases are processed differently in our brains. The different brain activations between genitive case processing and nominative/accusative case processing may be due to the difference in structural complexity between them.  相似文献   

14.
A central question in cognitive neuroscience is whether mechanisms exist that are specialized for particular domains. One of the most commonly cited examples of a domain-specific competence is the human ability to recognize upright faces. However, according to a widely discussed alternative hypothesis, face recognition is instead performed by mechanisms specialized for processing any object class for which an individual has expertise. Faces, according to this domain-general hypothesis, are just one example of an expert class. Nonface object expertise has been intensively investigated using a training procedure involving an artificial stimulus class known as greebles. A key prediction of this hypothesis is that individuals with face recognition impairments will also have impairments with other categories that control subjects have expertise with. Our results show that a man with severe prosopagnosia performed normally throughout the standard greeble training procedure. These findings indicate that face recognition and greeble recognition rely on separate mechanisms.  相似文献   

15.
付玲 《生物物理学报》2007,23(4):314-322
大脑功能的成像检测在认知神经科学领域具有极其重要的意义。现代光子学技术的发展为认知脑成像提供了新的研究手段,在神经系统信息处理机制研究中发挥重要作用。文章介绍了在神经元、神经元网络、特定脑皮层功能构筑以及系统与行为等不同层次开展神经系统信息处理机制研究的各种光学成像技术,包括多光子激发荧光显微成像、内源信号光学成像、激光散斑成像和近红外光学成像等,并评述了这些有特色的光学成像技术在多层次获取和分析神经信息中的研究进展。  相似文献   

16.

Background

One of the most debated issues in the cognitive neuroscience of language is whether distinct semantic domains are differentially represented in the brain. Clinical studies described several anomic dissociations with no clear neuroanatomical correlate. Neuroimaging studies have shown that memory retrieval is more demanding for proper than common nouns in that the former are purely arbitrary referential expressions. In this study a semantic relatedness paradigm was devised to investigate neural processing of proper and common nouns.

Methodology/Principal Findings

780 words (arranged in pairs of Italian nouns/adjectives and the first/last names of well known persons) were presented. Half pairs were semantically related (“Woody Allen” or “social security”), while the others were not (“Sigmund Parodi” or “judicial cream”). All items were balanced for length, frequency, familiarity and semantic relatedness. Participants were to decide about the semantic relatedness of the two items in a pair. RTs and N400 data suggest that the task was more demanding for common nouns. The LORETA neural generators for the related-unrelated contrast (for proper names) included the left fusiform gyrus, right medial temporal gyrus, limbic and parahippocampal regions, inferior parietal and inferior frontal areas, which are thought to be involved in the conjoined processing a familiar face with the relevant episodic information. Person name was more emotional and sensory vivid than common noun semantic access.

Conclusions/Significance

When memory retrieval is not required, proper name access (conspecifics knowledge) is not more demanding. The neural generators of N400 to unrelated items (unknown persons and things) did not differ as a function of lexical class, thus suggesting that proper and common nouns are not treated differently as belonging to different grammatical classes.  相似文献   

17.
This paper presents a functional brain-imaging strategy designed to isolate neural correlates of consciousness in humans. This strategy is based on skill learning. In the example presented (rapidly generating verbs for visually presented nouns), a cognitive skill is examined before and after practice. As shown, there are marked qualitative differences in the neural circuitry supporting performance of this task in the naive and practised state that include, importantly, both increases and decreases from the baseline activity of the brain.  相似文献   

18.
This research detects the most common words recurring in 326 adolescents' dream language. The analyzed dreams have been previously recorded and then transcribed. Grouping words, we obtained the frequency of the main parts of speech (nouns, verbs, adjectives and pronouns). Among the nouns, far more frequently represented are terms that refer to important objects of an affective relation. Other significant nouns relate to objects linked to both familial and extra-familial environments. Words related to family relations declined in frequency as age increased and were substituted by terms that refer to relations among friends and to the external world and its objects. Some of these results can be usefully compared with the conclusions derived from the application of other methods of content analysis. This method using dream language analysis could be applied to research concerning dream content, also through specific dictionaries (groups of words defined and classified in relation to a certain theme).  相似文献   

19.
Communicative interactions involve a kind of procedural knowledge that is used by the human brain for processing verbal and nonverbal inputs and for language production. Although considerable work has been done on modeling human language abilities, it has been difficult to bring them together to a comprehensive tabula rasa system compatible with current knowledge of how verbal information is processed in the brain. This work presents a cognitive system, entirely based on a large-scale neural architecture, which was developed to shed light on the procedural knowledge involved in language elaboration. The main component of this system is the central executive, which is a supervising system that coordinates the other components of the working memory. In our model, the central executive is a neural network that takes as input the neural activation states of the short-term memory and yields as output mental actions, which control the flow of information among the working memory components through neural gating mechanisms. The proposed system is capable of learning to communicate through natural language starting from tabula rasa, without any a priori knowledge of the structure of phrases, meaning of words, role of the different classes of words, only by interacting with a human through a text-based interface, using an open-ended incremental learning process. It is able to learn nouns, verbs, adjectives, pronouns and other word classes, and to use them in expressive language. The model was validated on a corpus of 1587 input sentences, based on literature on early language assessment, at the level of about 4-years old child, and produced 521 output sentences, expressing a broad range of language processing functionalities.  相似文献   

20.
Within the alternative concepts of “two-system” and “single-system” language models, brain mechanisms for the generation of regular and irregular forms of Russian verbs have been studied. The evoked EEG activity was recorded in 19 channels with random alternation of different speech-morphology operations. The infinitives of imperfective verbs that belong either to the productive group (conventionally, the default, or regular, class) or to the unproductive group (conventionally, the irregular class) were presented to healthy subjects. The subjects were to produce the first-person present-time forms of these verbs. The results of the analysis of the event-related potentials (ERPs) of 22 subjects are presented. Statistically valid ERP amplitude distinctions between the verb groups are found only in latencies of 600–850 ms in the central and parietal zones of the cortex. The peak values of the irregular-verb potentials are negative in this region in relation to the peak values of the regular-verb potentials. The findings are interpreted as the effect of various complexities of mental work with verbs of different groups and do not support the hypothesis of the universality of the two-system brain mechanism for processing regular and irregular language phenomena.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号