场景知觉及其研究范式

场景知觉关注的是人如何知觉和加工复杂的真实环境信息。场景包括物体和背景两个重要的组成部分,根据复杂性与真实性程度,场景刺激材料可以分为三种不同的类型。已有研究主要从自上而下和自下而上两种方式来解释场景知觉中信息的提取和加工,也有研究试图从二者交互的角度来进行解释。此外,基于不同的实验目的和技术,研究者分别采用了眼动、背景提示、物体觉察、变化觉察和点线索追随几种不同的研究范式来探讨场景信息的知觉问题。场景知觉研究在场景的定义、不同范式间的整合、研究内部效度和不同加工阶段的加工方式四个方面还需要进一步深入和探讨     

视觉短时记忆与视知觉的信息整合

与知觉整合和跨眼跳的信息整合一样,视觉短时记忆与视知觉的信息整合也是人们加工并保持整体性场景知觉的重要前提条件。近年来研究者们使用空白单元格定位任务进行了一些研究,试图寻求视觉短时记忆与视知觉信息整合的实验证据并探讨其整合机制。该文对已有的相关实验范式、实验证据和整合机制进行了介绍并加以分析,并指出未来研究可以在行为数据的基础上结合眼动和脑成像的数据寻求汇聚性证据     

生物运动及其在社会认知障碍研究中的应用

人类对生物运动具有较强的视觉敏感性,即使在视觉线索有限的情况下,仍能提取其中的社会性信息。本研究系统梳理了当前生物运动视知觉实验研究涉及的各类社会性信息,并归纳分析社会认知缺陷与生物运动视知觉加工之间的内在联系,以期促进对生物运动视知觉加工心理机制问题的深入探讨     

阈下知觉的加工水平及其发生条件—— 基于视觉掩蔽启动范式的视角

Dehaene等(1998)和Greenwald等(1996)的研究通过在方法上的完善, 为阈下知觉的存在提供了确凿的证据。但是阈下知觉可以达到什么样的深度这一问题尚仍然存在争议, 有研究者认为阈下知觉可以达到语义加工的水平, 而有的研究者认为阈下知觉只是对刺激视觉特征的一种浅层加工, 并形成了一些非语义加工的假说。在以往研究的基础上, 本研究通过完善实验范式, 分别采用图片、字词作为实验材料对阈下知觉的深度和影响因素进行探讨。实验1和实验2立据于阈下非语义加工的各种理论, 为阈下语义加工的存在提供了证据。同时实验2表明, 阈下知觉达到的水平取决于靶子集的大小, 更确切的说取决于被试对靶刺激进行了何种水平的加工。     

场景主旨的层级加工：来自注意瞬脱范式的证据

场景主旨加工的层级优先性及其对注意资源的需求一直备受关注。本研究采用注意瞬脱范式,记录被试完成面孔再认任务和四种时间延迟条件下不同层级场景主旨分类任务的正确率。结果发现,上级水平场景主旨分类任务的正确率没有出现注意瞬脱效应,而基本水平的场景主旨分类任务的正确率出现了注意瞬脱效应,前者高于后者;并且当进行上级水平场景主旨分类任务时,面孔再认的正确率显著高于进行基本水平场景主旨分类任务时的正确率。由此可见,场景主旨的层级水平调节场景主旨加工对注意资源的需求,支持场景主旨加工具有上级水平优势的观点。     

偏侧化颜色范畴知觉不依赖于语言?

本研究探讨了偏左脑颜色范畴知觉依赖于语言还是范畴。三组被试分别完成无干扰、语言加工干扰和范畴加工干扰视觉搜索任务。结果发现：无干扰组、语言加工干扰组和范畴加工干扰组的视觉搜索任务中分别出现了偏左脑颜色范畴知觉、左脑劣势颜色范畴知觉和无偏侧化颜色范畴知觉。此结果表明,偏左脑颜色范畴知觉可能主要是语言范畴作为一种范畴对颜色知觉的影响效应,但语言范畴的语言属性也会对颜色知觉产生影响。     

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。     

场景主旨对恐惧刺激加工影响的ERP研究

背景的情绪属性对恐惧面孔早期加工产生影响,但场景主旨的含义属性与恐惧刺激加工的关系并不清楚。以门和蛇的合成图片探讨不同任务的场景主旨加工及与其中恐惧刺激加工相互影响的脑机制,结果发现场景主旨信息对恐惧刺激加工存在影响。P1波幅的恐惧主效应显著,场景主旨的早期加工受到刺激图片恐惧属性的影响。N2在场景上主效应显著,即N2受到刺激图片情绪属性和实验任务的共同影响。     

视觉掩蔽研究现状及展望

视觉掩蔽是指某个物体因另一在空间或时间上与其相邻的物体的呈现而导致可见度降低的现象。目前,掩蔽的研究集中于那些涉及到特征、目标和场景表征,注意控制机制,以及现象知觉有关的加工等。该综述主要介绍了视觉掩蔽的概念和范式,研究的典型现象及参数,并介绍了相关的神经科学研究,概述并评论了4类重要的视觉掩蔽理论模型：知觉修正、双通道、边界轮廓系统以及目标替换。最后讨论了目前视觉掩蔽研究遇到的一些困难和挑战,包括刺激与任务的不统一带来的影响、神经科学方法的局限性以及模型模拟的复杂性,并从神经意识相关、功能性观点与模型发展三方面对视觉掩蔽未来的研究方向进行了展望。     

镜像等效或守恒及其打破：从行为到认知神经机制的研究证据

镜像等效或守恒是动物与人类个体对两侧对称自然物体的一种进化自适应加工。但是, 这种知觉特性会妨碍包含镜像字符的文字阅读学习。阅读者有必要学会利用镜像泛化抑制的“去学习”机制, 打破镜像等效或守恒, 以获得识别镜像字符的能力。这一过程中, 左侧梭状回皮层通过与早期视觉皮层、顶叶皮层和口语脑网络的交互作用, 逐渐发展出一个可以识别镜像字符的视觉词形区(visual word form area, VWFA)。今后的研究需要关注两半球及其连合纤维在镜像等效或守恒加工中的作用、镜像泛化与抑制的详尽加工机制及其对镜像书写的影响、正常汉语儿童的汉字镜像泛化加工等问题。     

The importance of information localization in scene gist recognition

People can recognize the meaning or gist of a scene from a single glance, and a few recent studies have begun to examine the sorts of information that contribute to scene gist recognition. The authors of the present study used visual masking coupled with image manipulations (randomizing phase while maintaining the Fourier amplitude spectrum; random image structure evolution [RISE]; J. Sadr & P. Sinha, 2004) to explore whether and when unlocalized Fourier amplitude information contributes to gist perception. In 4 experiments, the authors found that differences between scene categories in the Fourier amplitude spectrum are insufficient for gist recognition or gist masking. Whereas the global 1/f spatial frequency amplitude spectra of scenes plays a role in gist masking, local phase information is necessary for gist recognition and for the strongest gist masking. Moreover, the ability to recognize the gist of a target image was influenced by mask recognizability, suggesting that conceptual masking occurs even at the earliest stages of scene processing.     

视空工作记忆负载对场景主旨加工的影响

本研究采用工作记忆任务和场景辨别任务相结合的双任务范式探究客体工作记忆负载 (实验1)和空间工作记忆负载 (实验2) 对场景主旨辨别的影响。结果发现: (1) 与无负载条件相比, 客体负载条件下的非参辨别力指数(A’)明显下降, 而空间负载条件下A’无明显变化; (2) 随着场景图片呈现时间的延长, 场景辨别任务的A’逐渐提高; (3) 对自然场景和人工场景匹配情况下的A’ 明显高于对自然与自然或者人工与人工匹配情况下的A’。由此可见, 场景主旨识别, 特别是基本水平的场景主旨辨别, 与客体工作记忆共享部分认知资源, 而不与/很少与空间工作记忆共享认知资源; 在识别过程中, 上级水平范畴识别优先于基本水平范畴识别, 进一步支持了上级水平范畴优先的主旨层级加工观点。     

The relative contribution of scene context and target features to visual search in scenes

Many experiments have shown that knowing a targets visual features improves search performance over knowing the target name. Other experiments have shown that scene context can facilitate object search in natural scenes. In this study, we investigated how scene context and target features affect search performance. We examined two possible sources of information from scene context—the scenes gist and the visual details of the scene—and how they potentially interact with target-feature information. Prior to commencing search, participants were shown a scene and a target cue depicting either a picture or the category name (or no-information control). Using eye movement measures, we investigated how the target features and scene context influenced two components of search: early attentional guidance processes and later verification processes involved in the identification of the target. We found that both scene context and target features improved guidance, but that target features also improved speed of target recognition. Furthermore, we found that a scenes visual details played an important role in improving guidance, much more so than did the scenes gist alone.     

Early conceptual and linguistic processes operate in independent channels

Language and concepts are intimately linked, but how do they interact? In the study reported here, we probed the relation between conceptual and linguistic processing at the earliest processing stages. We presented observers with sequences of visual scenes lasting 200 or 250 ms per picture. Results showed that observers understood and remembered the scenes' abstract gist and, therefore, their conceptual meaning. However, observers remembered the scenes at least as well when they simultaneously performed a linguistic secondary task (i.e., reading and retaining sentences); in contrast, a nonlinguistic secondary task (equated for difficulty with the linguistic task) impaired scene recognition. Further, encoding scenes interfered with performance on the nonlinguistic task and vice versa, but scene processing and performing the linguistic task did not affect each other. At the earliest stages of conceptual processing, the extraction of meaning from visually presented linguistic stimuli and the extraction of conceptual information from the world take place in remarkably independent channels.     

Natural scenes can be identified as rapidly as individual features

Can observers determine the gist of a natural scene in a purely feedforward manner, or does this process require deliberation and feedback? Observers can recognise images that are presented for very brief periods of time before being masked. It is unclear whether this recognition process occurs in a purely feedforward manner or whether feedback from higher cortical areas to lower cortical areas is necessary. The current study revealed that the minimum presentation time required to identify or to determine the gist of a natural scene was no different from that required to determine the orientation or colour of an isolated line. Conversely, a visual task that would be expected to necessitate feedback (determining whether an image contained exactly six lines) required a significantly greater minimum presentation time. Assuming that the orientation or colour of an isolated line can be determined in a purely feedforward manner, these results indicate that the identification and the determination of the gist of a natural scene can also be performed in a purely feedforward manner. These results challenge a number of theories of visual recognition that require feedback.     

Scene context influences without scene gist: Eye movements guided by spatial associations in visual search

Although the use of semantic information about the world seems ubiquitous in every task we perform, it is not clear whether we rely on a scene’s semantic information to guide attention when searching for something in a specific scene context (e.g., keys in one’s living room). To address this question, we compared contribution of a scene’s semantic information (i.e., scene gist) versus learned spatial associations between objects and context. Using the flash-preview–moving-window paradigm Castelhano and Henderson (Journal of Experimental Psychology: Human Perception and Performance 33:753–763, 2007), participants searched for target objects that were placed in either consistent or inconsistent locations and were semantically consistent or inconsistent with the scene gist. The results showed that learned spatial associations were used to guide search even in inconsistent contexts, providing evidence that scene context can affect search performance without consistent scene gist information. We discuss the results in terms of hierarchical organization of top-down influences of scene context.     

The influence of color on the perception of scene gist

In 3 experiments the authors used a new contextual bias paradigm to explore how quickly information is extracted from a scene to activate gist, whether color contributes to this activation, and how color contributes, if it does. Participants were shown a brief presentation of a scene followed by the name of a target object. The target object could be consistent or inconsistent with scene gist but was never actually present in the scene. Scene gist activation was operationalized as the degree to which participants respond "yes" to consistent versus inconsistent objects, reflecting a response bias produced by scene gist. Experiment 1 demonstrated that scene gist is activated after a 42-ms exposure and that the strength of the activation increases with longer presentation durations. Experiments 2 and 3 explored the contribution of color to the activation of scene gist. The results revealed that color has an influence across a wide variety of scenes and is directly associated with scene gist.     

Infants detect changes in everyday scenes: The role of scene gist

When watching physical events, infants bring to bear prior knowledge about objects and readily detect changes that contradict physical rules. Here we investigate the possibility that scene gist may affect infants, as it affects adults, when detecting changes in everyday scenes. In Experiment 1, 15-month-old infants missed a perceptually salient change that preserved the gist of a generic outdoor scene; the same change was readily detected if infants had insufficient time to process the display and had to rely on perceptual information for change detection. In Experiment 2, 15-month-olds detected a perceptually subtle change that preserved the scene gist but violated the rule of object continuity, suggesting that physical rules may overpower scene gist in infants’ change detection. Finally, Experiments 3 and 4 provided converging evidence for the effects of scene gist, showing that 15-month-olds missed a perceptually salient change that preserved the gist and detected a perceptually subtle change that disrupted the gist. Together, these results suggest that prior knowledge, including scene knowledge and physical knowledge, affects the process by which infants maintain their representations of everyday scenes.     

Learning to attend: a connectionist model of situated language comprehension

Evidence from numerous studies using the visual world paradigm has revealed both that spoken language can rapidly guide attention in a related visual scene and that scene information can immediately influence comprehension processes. These findings motivated the coordinated interplay account ( Knoeferle & Crocker, 2006 ) of situated comprehension, which claims that utterance-mediated attention crucially underlies this closely coordinated interaction of language and scene processing. We present a recurrent sigma-pi neural network that models the rapid use of scene information, exploiting an utterance-mediated attentional mechanism that directly instantiates the CIA. The model is shown to achieve high levels of performance (both with and without scene contexts), while also exhibiting hallmark behaviors of situated comprehension, such as incremental processing, anticipation of appropriate role fillers, as well as the immediate use, and priority, of depicted event information through the coordinated use of utterance-mediated attention to the scene.