羞怯与非羞怯大学生在早期面孔加工中的差异——来自ERP的电生理学证据

羞怯与社会认知密切相关,而面孔识别是人们社会生活中的一项重要的社会认知功能。目前关于羞怯的电生理学研究大多关注表情的效价效应和面孔的新旧效应对羞怯个体面孔加工的影响,却忽视了羞怯个体在基本的面孔识别能力——面孔-物体识别中可能存在的认知神经差异。因此,本研究采用ERP技术,使用GO/Nogo范式的面孔-物体识别任务,对17名羞怯大学生和17名非羞怯大学生在面孔结构编码中的N170成分进行考察,以期发现不同羞怯水平大学生在早期面孔加工中的认知神经差异。本研究发现,非羞怯大学生对面孔结构具有加工优势,识别面孔时,非羞怯大学生的N170波幅显著大于羞怯大学生的N170波幅,识别物体时则不存在组间差异;N170是面孔识别的特异性成分,面孔诱发的N170波幅显著大于物体诱发的N170波幅;识别面孔时,N170表现出大脑右半球的加工优势。     

文字与面孔识别的半球偏侧化互补模式的竞争性发展机制

成人的大脑左侧VWFA对正字法信息更敏感,而右侧FFA优先处理面孔信息。然而,这种偏侧化互补模式的发展机制还亟待阐明。神经元再利用假设认为,在文字阅读学习过程中,文字识别会与面孔表征在左侧FG竞争神经加工资源,导致文字识别出现VWFA的左侧化,并推动了面孔识别FFA的右侧化。分布式半球组织的观点提出了神经计算加工三原则,试图系统阐释文字与面孔偏侧化竞争性发展的多层次双向动态加工机制。近期,FG的结构分区与功能特征研究取得了一些新成果,并据此构建了一个文字与面孔识别的多维度计算加工模型。因此,有必要基于神经元再利用假设和分布式半球组织的观点,并结合FG的结构与功能特征和近期研究证据,以系统探讨文字与面孔识别的半球偏侧化互补模式竞争性发展的认知神经加工机制。未来研究应进一步探究文字与面孔竞争加工的皮层空间位置和功能神经组织学基础、汉字与面孔竞争的加工机制、面孔识别的右侧化发展机制以及数字和音符阅读学习导致大脑可塑性改变的机制。     

面孔倒置效应的研究与理论述评

面孔倒置效应是指, 个体对倒置面孔的再认成绩显著低于对正立面孔的再认成绩, 而且, 与普通物体的倒置效应相比, 面孔的倒置效应更大。研究者们针对面孔倒置效应提出了多种理论假说, 两种主要的理论解释是：第一, 倒置面孔破坏了面孔的结构特征, 影响了面孔的整体加工, 所以, 个体对倒置面孔的再认成绩较差; 第二, 眼睛在面孔加工中起重要作用, 尤其在倒置面孔中的作用更明显, 使得倒置面孔N170波幅较高。ERP和fMRI研究提示, 未来研究需要进一步明确眼睛、注意等在面孔倒置效应中的作用。     

面孔识别的“特殊性”

面孔是复杂的、多维的、自然的特殊视觉刺激,在人类生活中占据非常重要的地位。面孔识别可以不受大不小、光线、背景、位置、年龄、表情、姿势等的影响,因此设想面孔识别是否具有与一般物体识别和字词识别不同的加工过程?本文首先提供了有关面孔识别“特殊”的证据,然后列举了占统治地位的关于面孔属于整体化表征的各种假说;又从神经心理学角度阐明了面孔识别系统的功能特点;指出近期在计算机科学领域很好地模拟了面孔的整体性表征。最后的结论是,与字词、物体识别比较,面孔识别的特殊性在于其程度而非种类,仅仅在量上而非质上与物体识别及字词识别有差异。一定程度上讲,面孔只是一个特殊的物体。     

面孔情绪识别过程中的多通道效应

摘 要 面孔情绪识别过程中的多感觉通道效应指参与刺激加工的各个通道对面孔表情认知的综合影响。研究者们通过行为实验、事件相关电位以及脑成像技术等对该过程中的多个获取信息的通道进行研究,肢体表情、情绪性声音、特定气味能系统地影响面孔表情的情绪识别。一系列的研究对多通道效应的作用时间、潜在作用机制、相关激活脑区进行了探索。未来的研究可以整合脑网络的技术,并结合其他学科的新技术以更细致具体地考察这些通道下信息的物理属性所起的作用。 关键词 面孔表情 多通道效应 面孔情绪识别 肢体表情 情绪性声音 嗅觉信号     

场景知觉中物体加工的背景效应

在场景中加工物体信息时, 与物体相伴随的背景会影响对物体的加工。这种物体加工的背景效应在很多的研究中得到了证实。场景知觉中的背景效应有不同的表现, 对于场景中物体识别和背景的关系, 研究者从功能独立、相互作用和背景引导等理论角度给予了解释。其次, 自然场景材料和非自然场景材料所提供的背景信息不同, 研究者从不同的刺激水平探讨了这二者之间的背景效应存在的差异。同时, 随着技术的进步, 研究者也在探讨场景知觉过程中物体加工背景效应的生理机制, 并发现了一些与物体识别的背景效应有关的脑区定位。这些相关的研究为深入了解人是如何知觉和加工真实而复杂的环境提供了新的研究内容和视角。     

婴儿面孔种族效应的发展：经验的作用

面孔种族效应是指个体对本族面孔与他族面孔的加工存在差异,即对本族面孔的识别比他族面孔更快速、更准确,而对他族面孔的分类则优于本族面孔。经验是否以及如何影响面孔种族效应的发展,一直是研究者关注的焦点。近十几年,越来越多的学者对婴儿面孔种族效应进行了研究,已有成果主要涉及两个方面：（1）自然条件下婴儿面孔种族效应的出现与发展,即婴儿在面孔种族偏好、识别与分类以及面孔种族加工方式上的变化;（2）训练对婴儿面孔种族效应的影响。未来应丰富研究模式,增强实验材料的生态性,联合新的神经生理技术手段,进一步揭示婴儿经验对面孔种族效应的作用机制。     

身体姿势识别倒置效应量的连续性变化

以生理机制上整体可能身体姿势、整体不可能身体姿势和碎片身体姿势作为材料,系统操纵两个角度差为零的身体姿势偏离其竖直状态的角度,对错误率和反应时进行线性拟合。结果发现:(1)整体可能身体姿势、整体不可能身体姿势的识别错误率和反应时与其偏离直立状态角度之间可以拟合显著的线性关系,而碎片身体姿势的识别错误率和反应时与其偏离直立状态角度之间无法拟合显著的线性关系;(2)整体身体姿势(可能身体姿势和不可能的身体姿势)识别均出现了显著的倒置效应,而碎片身体姿势识别未出现倒置效应。这些结果表明身体姿势识别倒置效应量的延续性依赖于整体布局加工。     

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。     

非安全依恋可塑性的神经机制

非安全依恋可塑性是借助认知启动技术(例如安全依恋启动)使非安全依恋个体长期处于敏感和支持性的环境中, 从而唤醒个体积极的依恋经历, 使其对依恋关系形成新的认知图式, 最终实现非安全依恋个体内部工作模型的重构。本项目针对非安全依恋个体的认知加工缺陷, 采用安全依恋启动的方法探索非安全依恋可塑性的发生机制及相应的神经生理基础。项目拟从单次安全依恋启动对非安全依恋个体认知加工缺陷的改善效应、多任务条件下对重复安全启动效应的检验以及重复安全依恋启动效应的追踪研究三方面开展非安全依恋可塑性研究; 研究手段采用行为-生理-脑成像的技术, 从安全依恋启动的性质、方式和时间三个维度上系统地探究非安全依恋可塑性的发生机制与神经基础。非安全依恋可塑性研究为安全依恋研究提供了新视角, 研究提出的依恋图式重构理论是对安全基地图式理论的印证与发展, 对重复安全启动效应的检验及追踪研究试图为非安全依恋可塑性研究构建一套科学有效的评估标准。研究成果对于非安全依恋人群的干预训练、提升依恋安全感、维护心理健康具有重要价值。     

Conceptual knowledge attenuates viewpoint dependency in visual object recognition

Learning verbal semantic knowledge for objects has been shown to attenuate recognition costs incurred by changes in view from a learned viewpoint. Such findings were attributed to the semantic or meaningful nature of the learned verbal associations. However, recent findings demonstrate surprising benefits to visual perception after learning even noninformative verbal labels for stimuli. Here we test whether learning verbal information for novel objects, independent of its semantic nature, can facilitate a reduction in viewpoint-dependent recognition. To dissociate more general effects of verbal associations from those stemming from the semantic nature of the associations, participants learned to associate semantically meaningful (adjectives) or nonmeaningful (number codes) verbal information with novel objects. Consistent with a role of semantic representations in attenuating the viewpoint-dependent nature of object recognition, the costs incurred by a change in viewpoint were attenuated for stimuli with learned semantic associations relative to those associated with nonmeaningful verbal information. This finding is discussed in terms of its implications for understanding basic mechanisms of object perception as well as the classic viewpoint-dependent nature of object recognition.     

Facelikeness matters: A parametric multipart object set to understand the role of spatial configuration in visual recognition

There is a view that faces and objects are processed by different brain mechanisms. Different factors may modulate the extent to which face mechanisms are used for objects. To distinguish these factors, we present a new parametric multipart three-dimensional object set that provides researchers with a rich degree of control of important features for visual recognition such as individual parts and the spatial configuration of those parts. All other properties being equal, we demonstrate that perceived facelikeness in terms of spatial configuration facilitated performance at matching individual exemplars of the new object set across viewpoint changes (Experiment 1). Importantly, facelikeness did not affect perceptual discriminability (Experiment 2) or similarity (Experiment 3). Our findings suggest that perceptual resemblance to faces based on spatial configuration of parts is important for visual recognition even after equating physical and perceptual similarity. Furthermore, the large parametrically controlled object set and the standardized procedures to generate additional exemplars will provide the research community with invaluable tools to further understand visual recognition and visual learning.     

从面孔模块到马赛克──视觉特异性加工的脑机制

“脑功能的模块性”是视觉乃至整个认知神经科学的研究热点。特异性的面孔加工模块被当作是认知模块假说的最好证据。但综述跨学科的正反两方面实验证据表明,视觉加工存在特异性,并没有普遍的模块式的亚单元,而是“马赛克”镶嵌式的组构。     

Empirical tests of the recognition heuristic

The recognition heuristic postulates that individuals should choose a recognized object more often than an unrecognized one whenever recognition is related to the criterion. This behavior has been described as a one‐cue, noncompensatory decision‐making strategy. This claim and other assumptions were tested in four experiments using paired‐comparison tasks with cities and other geographical objects. The main results were (1) that the recognized object was chosen more often than the unrecognized one when the recognition cue was valid; (2) that participants' behavior did not reflect the recognition validity of their own knowledge; (3) that a less‐is‐more effect (i.e., better performance with less knowledge) was either absent or of only small size; and (4) that judgments were influenced by further knowledge, which could even compensate for the recognition cue. In sum, the recognition cue represents an important piece of knowledge in paired comparisons, but apparently not the only one. Copyright © 2006 John Wiley & Sons, Ltd.     

An ERP study on self-relevant object recognition

We performed an event-related potential study to investigate the self-relevance effect in object recognition. Three stimulus categories were prepared: SELF (participant's own objects), FAMILIAR (disposable and public objects, defined as objects with less-self-relevant familiarity), and UNFAMILIAR (others' objects). The participants' task was to watch the stimuli passively. Results showed that left-lateralized N250 activity differentiated SELF and FAMILIAR from UNFAMILIAR, but SELF and FAMILIAR were not differentiated. In the later time-course, SELF was dissociated from FAMILIAR, indicating the self-relevance effect in object recognition at this stage. This activity did not show consistent lateralization, in contrast to previous studies reporting right lateralization in self-relevant face and name recognition. We concluded that in object recognition, self-relevance was processed by higher-order cognitive functions later than 300ms after stimulus onset.     

Negative priming of unattended part primes: Implications for models of holistic and analytic processing in object recognition

The “hybrid” model of object recognition (Hummel, 2001) proposes that unattended objects are processed holistically, while attended objects are processed both holistically and analytically. Supporting evidence for this claim was reported by Thoma, Hummel, and Davidoff (2004) who showed that, unlike whole object primes, unattended split object parts (presumed to require analytic processing) do not elicit repetition priming. Here we tested the generality of this finding by contrasting priming for whole and part prime stimuli as a function of prime informativeness and by modifying the design so that both unattended whole and part prime displays contained a single perceptual object. Unlike Thoma et al. (2004) the results showed negative (rather than an absence of) priming for unattended half object primes. These findings place new constraints on theoretical models of the role of attention in object recognition.     

Distorting Face Representations in Newborn Brains

What role does experience play in the development of face recognition? A growing body of evidence indicates that newborn brains need slowly changing visual experiences to develop accurate visual recognition abilities. All of the work supporting this “slowness constraint” on visual development comes from studies testing basic-level object recognition. Here, we present the results of controlled-rearing experiments that provide evidence for a slowness constraint on the development of face recognition, a prototypical subordinate-level object recognition task. We found that (1) newborn chicks can rapidly develop view-invariant face recognition and (2) the development of this ability relies on experience with slowly moving faces. When chicks were reared with quickly moving faces, they built distorted face representations that largely lacked invariance to viewpoint changes, effectively “breaking” their face recognition abilities. These results provide causal evidence that slowly changing visual experiences play a critical role in the development of face recognition, akin to basic-level object recognition. Thus, face recognition is not a hardwired property of vision but is learned rapidly as the visual system adapts to the temporal structure of the animal's visual environment.     

可操作物体识别过程中的两种操作动作表征

已有大量研究表明, 视觉背侧通路中的背侧−背侧通路和腹侧−背侧通路分别表征与物体相关的抓握和使用动作, 形成结构性和功能性操作动作表征。这两种操作动作表征在神经基础、激活条件、时间进程, 以及与长时记忆的联系方面都存在差异, 并且共同参与到可操作物体的识别过程中。关于结构性和功能性操作动作表征的研究不仅证明了操作动作信息对于可操作物体识别的重要性, 而且对于深入研究物体如何在大脑中表征具有重要意义。     

View combination: a generalization mechanism for visual recognition

We examined whether view combination mechanisms shown to underlie object and scene recognition can integrate visual information across views that have little or no three-dimensional information at either the object or scene level. In three experiments, people learned four “views” of a two dimensional visual array derived from a three-dimensional scene. In Experiments 1 and 2, the stimuli were arrays of colored rectangles that preserved the relative sizes, distances, and angles among objects in the original scene, as well as the original occlusion relations. Participants recognized a novel central view more efficiently than any of the Trained views, which in turn were recognized more efficiently than equidistant novel views. Experiment 2 eliminated presentation frequency as an explanation for this effect. Experiment 3 used colored dots that preserved only identity and relative location information, which resulted in a weaker effect, though still one that was inconsistent with both part-based and normalization accounts of recognition. We argue that, for recognition processes to function so effectively with such minimalist stimuli, view combination must be a very general and fundamental mechanism, potentially enabling both visual recognition and categorization.     

Novel object detection and recognition system based on points of interest selection and SVM classification

Due to the progression in computer vision technology, object recognition systems have gained considerable research interest. Though there are numerous object recognition systems in the literature, there is always a constant demand for better object recognition systems. Taking this as a challenge, this work proposes a novel object recognition system based on points of interest and feature extraction. Initially, the points of interest of the image are selected by means of Derivative Kadir-Brady (DKB) detector and the neighbourhood pixels of a particular window size are selected for further processing. The gabor and curvelet features are extracted from the area of interest, followed by the Support Vector Machine (SVM) classification. The performance of the proposed object recognition system is evaluated against three analogous techniques in terms of accuracy, precision, recall and F-measure. On experimental analysis, it is proven that the proposed approach outperforms the existing approaches and the performance of the proposed work is satisfactory.