对“物体内注意转移”优势效应之机制的进一步检验

针对“选择性注意基于空间还是基于物体”的问题,从Ｅｇｌｙ等与Ｖｅｃｅｒａ等的争论出发,考察“物体内注意转移”的优势效应是否与空间因素有关,首先,与以往研究结果一致,观察到：与提示无效时相比,空间提示有效时被试对目标的反应较快,这提示基于空间的注意成分的存在;通过改变两个背景物体的形状和颜色,减弱两者之间的知觉组织之后,还发现“物体内注意转移”的优势效应与空莘距离无关,后一结果为基于物体的选择性注意     

物体表征强度对基于动态物体的注意的影响

基于物体的注意已得到许多静态物体实验的证实, 然而, 对注意分配如何受动态物体影响的研究较少, 存在提示物体假设和动态更新假设两种观点。提示物体假设认为基于物体的注意由最初的物体决定, 而动态更新假设则认为由变化之后的物体决定。动态物体的注意研究还发现了即时物体效应, 即注意基于新物体进行。对于物体变化时注意究竟基于旧物体还是新物体, 新旧物体的相对物体表征强度在其中起决定作用; 当提示物体表征较强时表现为提示物体(即旧物体)决定注意分配, 而当即时物体表征较强时表现为即时物体(即新物体)决定注意分配。相对物体表征强度的概念对理解物体动态变化情况下基于物体的注意的分配以及解决相关理论之冲突可能有重要作用。     

组织竞争与教师组织认同的关系机制

采用组织认同问卷、组织认同图解量表、组织竞争问卷、组织同一性知觉问卷和组织声望知觉问卷对700名教师进行施测,考察组织竞争影响教师组织认同的关系机制.结果表明:外部竞争、内部竞争、组织同一性知觉、组织声望知觉均与教师组织认同呈显著正相关;外部竞争通过两条路径影响教师的组织认同水平,一是外部竞争—组织同一性知觉—组织认同,二是外部竞争—组织同一性知觉—组织声望知觉—组织认同;内部竞争通过组织声望知觉影响教师的组织认同水平,即内部竞争—组织声望知觉—组织认同.     

语法性别对认知的影响及其机制

语法性是许多语言中普遍存在的现象。它本质上属于句法属性,但是一定程度上关联着语义,而且会影响个体对物体的分类、知觉、认知加工,以及对二语的学习等认知活动,其对认知的影响程度受任务、语言、语法性透明度等因素调节。语法性影响认知的机制主要有概念水平上的相似性假设;生物性假设;词汇水平上的双选择模型。未来的研究要进一步探究语法性的认知机制、二语学习中语法性习得的认知过程、语法性不同形式性别差异影响的机制。     

实物形状的知觉相似性对视觉隐喻加工的影响

视觉隐喻是众多研究者比较关注的领域, 当前多以物体简笔画、漫画及广告等方面的研究为主, 但对与生活密切相关的实物的视觉隐喻研究甚少。因此研究采用掩蔽启动范式、李克特9点量表及语音生成等研究方法, 在物体概念类型(概念相同、概念相异)及形状类型(形状相似、形状相异)条件下, 针对实物图片的形状知觉相似性是否对视觉隐喻加工产生影响进行探讨。结果发现无论物体概念是否相同, 形状相似性对个体的物体识别具有“促进”作用, 并有利于视觉隐喻加工; 在物体识别中, 当两个物体概念不同时, 个体会试图建立一个特设类别来对形状相似的物体进行归类, 从而实现了视觉隐喻的加工。因此研究进一步证明了实物形状的知觉相似性有利于视觉隐喻的加工。     

知觉组织影响时序知觉的认知机制:ERP研究的证据

以往研究显示,知觉组织影响时序知觉,采用ERP技术拟探讨知觉组织影响时序知觉的认知机制。采集23名被试完成同时判断任务的脑电数据。行为结果发现,知觉组织影响时序知觉,具体表现为知觉组织条件的同时判断频率显著高于非知觉组织条件。ERPs结果发现,在P1和P2成分上,知觉组织条件与非知觉组织条件引发的波幅没有显著差异; 而在N1成分上,知觉组织条件诱发的N1波幅显著大于非知觉组织条件。这表明,知觉组织对时序知觉的影响可能发生在视觉刺激加工的早期阶段,视觉刺激的知觉组织先于时序信息加工。     

大学生的气味词分类—— 基于语义相似性和知觉相似性的探讨

通过两个实验, 考察了大学生对60个气味词的基于语义相似性和基于知觉相似性的分类, 并运用多维标度法和聚类分析法进行分析。结果发现：(1)在语义水平上, 大学生根据发出气味的物体的功能(与食物有关/与食物无关)和语义性质(人造物/自然物)对气味词分类; (2)在表象水平上, 大学生根据气味的感觉情调(气味的愉悦度)和强度(浓度)对气味词分类; (3)气味词具有粗略的语义特征, 原型在气味词概念组织中具有重要作用; (4)男、女大学生对于气味词的分类基本一致, 但在具体项目上存在着性别差异。     

视知觉组织在整体知觉中的作用--脑损伤病人的实验研究

本实验研究大脑损伤如何影响复合图形的整体知觉。三例病人脑损伤部位分别在大脑枕区、顶区、颞区、额区及基底节和豆状核。复合图形被呈现给病人和正常对照被试。强迫选择识别等任务表明,当空间相邻性决定局部图形的知觉组织时,病人识别整体性质的正确率高于(ZD和FL)或略底于(GK)识别局部性质的正确率;当形状相似性决定局部图形的知觉组织时,病人识别整体性质的正确率显著降低,而识别局部性质的正确率受到的影响较小。在同样的任务中正常被试识别整体和局部性质的正确率受知觉组织因素的影响很小。这些结果提示大脑损伤对整体知觉的破坏可能主要通过影响基于形状相似性的知觉组织实现。     

用"你"表述物体的功能会抑制成因对分类的影响

已有研究显示物体的成因等变量会影响人造物概念的分类;但这种影响的中介变量为何,基于设计和基于用途的理论有不同的假设.实验采用物体自由命名任务,在陈述物体的功能时,操纵角色词的类型(旁观者"有人"和使用者"你"),比较被试对物体的命名在领域水平的分类倾向.结果发现,呈现"旁观者"角色词时,呈现或不呈现物体自然形成的成因故事会造成不同的分类倾向;但是在呈现"使用者"角色词时,成因故事对分类倾向的影响消失了.提示物体的功能是成因和分类的中介变量,支持基于用途的人造物分类模型.     

面孔-人格知觉中眼部线索及其效应

人们常常会基于他人面孔特征对其人格做出相应推论。在影响面孔-人格知觉的五官特征中, 眼部特征最具复杂性。总体上, 眼部线索可分为可变和不可变两大类。可变线索包括注视方向、眼睑开放程度与眼部区域的表情等; 不可变线索包括眼睛大小、巩膜着色程度、虹膜颜色以及巩膜暴露指数等。从以上线索效应的潜在作用机制来看, 可以将眼部线索分为三大类, 即受病理因素影响的眼部线索、与特定群体相关的眼部线索和受主观意识或生理因素调控的眼部线索。此外, 也进一步指出了未来研究还需加以考虑的其他眼部特征效应, 以及待拓展深入的研究视角。     

Visual exploration pattern in hemineglect

The analysis of eye movement parameters in visual neglect such as cumulative fixation duration, saccade amplitude, or the numbers of saccades has been used to probe attention deficits in neglect patients, since the pattern of exploratory eye movements has been taken as a strong index of attention distribution. The current overview of the literature of visual neglect has its emphasis on studies dealing with eye movement and exploration analysis. We present our own results in 15 neglect patients. The free exploration behavior was analyzed in these patients presenting 32 naturalistic color photographs of everyday scenes. Cumulative fixation duration, spatial distribution of fixations in the horizontal and vertical plane, the number and amplitude of exploratory saccades was analyzed and compared with the results of an age-matched control group. A main result of our study was that in neglect patients, fixation distribution of free exploration of natural scenes is not only influenced by the left–right bias in the horizontal direction but also by the vertical direction.     

汉语发展性阅读障碍儿童的视知觉学习*

研究采用知觉学习经典范式中的视觉搜索任务探讨汉语发展性阅读障碍儿童的知觉学习过程。研究考察了阅读障碍儿童与正常儿童在简单搜索任务、复杂搜索任务和限制时间的复杂搜索任务上的知觉学习特点。结果发现,阅读障碍儿童在复杂搜索任务中初始搜索时间显著长于正常控制组;在限制时间的复杂搜索任务中更进一步发现阅读障碍儿童的反应正确率显著低于正常控制组儿童;而且两组儿童视觉搜索任务的正确率与汉语阅读的识字量成绩存在显著相关。上述结果表明,汉语发展性阅读障碍儿童存在复杂搜索的知觉学习缺陷,这种缺陷可能在某种程度上与儿童的阅读技能发展有关。     

工作记忆内容对视知觉的功能性影响

工作记忆和知觉是人类信息加工系统中的两个基本认知结构, 阐明两者之间的功能关系对于揭示人类信息加工的本质规律具有重要和根本的科学意义。工作记忆和知觉可以在多个方面发生交互作用, 其中工作记忆内容对视知觉的影响就是一个很重要的方面。文章在系统回顾工作记忆内容影响视知觉的相关研究的基础上, 提出工作记忆内容可以引导知觉选择、增强知觉表征和改变知觉经验, 指出工作记忆中的自上而下调控机制可能是工作记忆内容影响知觉的神经基础。     

Perceptual Grouping and Motion Coherence in Visual Search

Search for a conjunction of form and motion is greatly affected by manipulations of phase in the target and nontarget motion sets. To test whether this finding can be best explained by perceptual grouping, we moved a random set of dots in phase or counterphase with target or nontarget motion. Perceptual grouping was found to have a dramatic effect on search performance. We propose that this interaction between perceptual grouping and visual search is governed by three general rules. Our data also provide convincing evidence of the preattentive organization of a visual display into surfaces defined by common motion.     

Visual attention and perceptual grouping.

Perceptual organization is thought to involve an analysis of both textural discontinuities and perceptual grouping. In earlier work, we found that textural discontinuities were detected normally even when visual attention was engaged elsewhere. Here we report how perceptual grouping is affected when visual attention is engaged by a concurrent visual task. To elicit perceptual grouping, we used the Gestalt demonstrations of grouping on the basis of proximity and of similarity. Four tasks were investigated, some requiring the observer to discriminate between horizontal and vertical grouping, and some requiring the observer to merely detect the presence or absence of grouping. Visual attention was engaged at the center of the display by a form identification task. The detection of a textural discontinuity served as a control task. Concurrent form identification conflicted with all four grouping tasks, resulting in a significant reduction of grouping performance in each case. No performance reduction was observed when either form identification or grouping discrimination was combined with the detection of a textural discontinuity. These results suggest that perceptual grouping and form identification compete for visual attention, whereas the detection of a textural discontinuity does not.     

Visual attention and perceptual grouping

Perceptual organization is thought to involve an analysis of bothtextural discontinuities andperceptual grouping. In earlier work, we found that textural discontinuities were detected normally even when visual attention was engaged elsewhere. Here we report how perceptual grouping is affected when visual attention is engaged by a concurrent visual task. To elicit perceptual grouping, we used the Gestalt demonstrations of grouping on the basis of proximity and of similarity. Four tasks were investigated, some requiring the observer to discriminate between horizontal and vertical grouping, and some requiring the observer to merely detect the presence or absence of grouping. Visual attention was engaged at the center of the display by a form identification task. The detection of a textural discontinuity served as a control task. Concurrent form identification conflicted with all four grouping tasks, resulting in a significant reduction of grouping performance in each case. No performance reduction was observed when either form identification or grouping discrimination was combined with the detection of a textural discontinuity. These results suggest that perceptual grouping and form identification compete for visual attention, whereas the detection of a textural discontinuity does not.     

Influence of Stimulus Salience and Attentional Demands on Visual Search Patterns in Hemispatial Neglect

Seventy-five left and right brain-damaged patients, with or without hemispatial neglect, and 40 age-matched control subjects were tested on cancellation tasks with two different visual textures modeled after Julesz (1981). In one condition (“preattentive”), target elements segregated easily from background elements and were perceived effortlessly. In the other (“attentive”), target elements did not segregate easily and could be detected only after prolonged focal scrutiny. Both controls and patients were more accurate and faster on the preattentive than attentive texture. However, only neglect patients were disproportionately impaired on the attentive texture, thus suggesting that unilateral neglect is exacerbated by the low visual salience of the stimuli and a higher engagement of focal attention. Thus, a simple bedside test may help to tell apart the level of visual information processing maximally impaired in neglect patients.     

Visual neglect and left-sided context effects

Patients with visual neglect generally fail to respond to an item placed on the left of a target location, even when both stimuli are situated in the right visual field. Little is known, however, about the level of processing for the unattended items. Two patients with left visual neglect served as subjects in several experiments measuring passive contextual effects of a left-sided item on responses to a focal target. The results reveal that a neglected item may influence the speed of responding. The findings are interpreted relative to the loci of context effects in normal subjects.     

Visual neglect in the first weeks after a stroke in the right hemisphere

The aim of the study was to characterize symptoms of visual neglect among patients who recently survived a stroke in the right hemisphere (RH), and to contribute to the understanding of change in symptoms during the first months after a RH stroke. Thirteen patients with a RH stroke and twenty controls were assessed by using standard neglect tests. Five patients were followed up by repetitive test sessions during the next four months. To assess more subtle symptoms, reaction-time (RT) measures derived from an experimental cue-target paradigm were included in the final test session. A high frequency of neglect symptoms was documented at the first test session. The changes in performance during the first weeks were characterized by a high inter-individual as well as a high intra-individual variability. Although the remission rate on standard tests was high in the follow-up study, the RT measures indicated sustained symptoms of visual extinction in all patients. The long-term implication of the changes of neglect symptoms during the first weeks after a stroke and signs of sustained symptoms of visual extinction calls for further longitudinal studies including a larger group of patients.