额叶与非额叶脑肿瘤患者分心记忆和符号数字作业的比较研究

本文以95例额叶、颞叶和顶枕叶脑肿瘤患者为被试,探讨了脑肿瘤部位同分心记忆和符号数字的关系。结果表明,额叶患者的故事意义分的分心消耗值显著高于正常人,其词的分心回忆和分心消耗值显著差于颞叶组,表明额叶在分心作业中较颞叶参与较多。右顶叶也有涉及分心注意较多的趋势,提示大脑前部可能与分心注意关系较密切。“符号数字”作业中,则“写”的作业有颞叶组好于额叶组,“说”的作业颞叶组好于顶枕组的趋势。     

心算加工的认知神经科学研究

近几年(1999-2005)有关心算加工的脑活动机制研究发现,类似九九乘法表这样的算术知识提取(如3×5)主要与左脑顶内沟有关,但当心算变得更复杂时(如26×38),左脑额叶下部出现明显激活,这表明心算与语言和工作记忆关系密切。另一方面,也存在不依赖于语言的即表现为视觉表象活动的心算,右脑的一些脑区在其中起了作用。简言之,所有与心算有关的脑区涉及到大脑前额皮层和颞顶枕联合皮层的综合作用,并总体表现为左脑优势,但具有特殊心算能力的人其心算还与右脑前额叶和颞叶内侧脑区的活动有关。     

默读汉字词的脑功能偏侧化成像研究

采用读词名的方法 ,对 12名正常大学生 ,运用功能性磁共振成像技术 (fMRI) ,研究了汉字词及假词视觉识别时的脑功能偏侧化现象。实验结果表明 ,汉字词激活左下额区 (BA4 5 )以及右颞叶 (BA2 1、2 2 )、右枕叶 (BA18) ,而假词除额区外表现出广泛的激活。此结果显示除左脑半球与汉字词加工密切相关外 ,右脑半球在汉字词加工中有一定参与但其确切作用有待进一步研究     

心算的加工机制：来自认知神经科学的研究

心算加工分编码（表征）、运算（或提取）和反应三个阶段,这三个阶段相互影响。不同输入形式的数字表征在顶叶的不同区域完成。算术知识提取主要与左脑顶内沟有关,但当心算变得更复杂时而需要具体运算时,左脑额叶下部出现明显激活。所有与心算有关的脑区涉及大脑前额皮层和颞顶枕联合皮层的综合作用,并总体表现为左脑优势,但估算、珠心算以及某些具有特殊心算能力的人的心算还依赖视空间表征,这与右脑额顶区和楔前叶的活动有关     

线方向判断测验在神经内,外科临床的应用与评价

对200名正常人及168例脑损害病人分别进行了线方向判断测验的测查。发现在对照组中,年龄、性别、文化水平对测验成绩均有一定的影响,尤以文化水平的影响最为显著。各病种组与对照组比较,发现脑梗塞组与脑肿瘤组成绩比外伤组和血管畸形组为差。同时还发现所有病种组右脑损害患者分数均低于左脑损害患者。     

额叶参与对新异联系的启动效应——来自脑损伤病人的证据

对新异联系的启动效应是内隐记忆的一种形式,又称联想启动。采用知觉辨认任务,探讨额叶损伤与联想启动的关系。25例额叶损伤病人及18例匹配的正常被试参与实验。结果表明,额叶受损病人辨认旧词对与重组词对的正确率没有明显差别;而且,轻度记忆损伤的额叶病人再认成绩正常,但联想启动值低于对照组,内隐记忆和外显数、坚持性反应数和语词流畅性等有中度相关。这些结果提示,额叶不仅与情节记忆、工作记忆等外显记忆有关,也参与了以非相关词对为材料的联想启动。     

成年人词语流畅性的年龄差异和词语记忆

本文以自觉健康的青年、中年和老年人78例为被试,研究了成年人口语、阅读和书写流畅性的年龄差异及其和词语记忆的关系。结果:1.大多数词语流畅能力以及词语记忆均为中年以后衰退,Stroop测验的读色字及读字色作业则中年即开始减退。2.除年龄因素外,词语流畅性还受被试者文化程度和测验内容的影响,同时还表现有文化因素或测验和年龄的交互作用。文化程度越低,测验难度越大,年龄差异越显著。3.词语流畅性和词语记忆有显著相关。这可能是由于两者都有较多的记忆和注意过程的参与。4.在两项颜色命名测验及说同类词作业中都见到女性优于男性的现象。     

逆行性遗忘、额叶与远期记忆的组织

通过对一例严重记忆障碍合并额叶损伤病人的逆行性遗忘的分析,对远期记忆的组织特点进行了探讨。被试的额叶功能受损较为明显。除顺行性遗忘外,患者的逆行性遗忘也较为严重。对病人进行的逆行性遗忘检测包括：著名人物测验、著名事件、一般知识测验和自传性记忆测验等。被试对著名人物、著名事件的回忆和再认成绩、以及有关个人的情节和语义记忆成绩均较低,但没有典型的随时间下降的趋势,而是呈平直斜率;患者儿童期的自传性记忆和公众事件记忆也受损。这两个特点均与内侧颞叶一间脑系统损伤的特点不同,提示额叶参与了远期记忆的提取等过程。     

抑郁倾向对合作的影响：双人同步近红外脑成像研究

抑郁人群不但表现出注意、记忆等个体认知层面的负性偏向, 还伴随有明显的社会认知障碍。已有研究在抑郁对社会认知的影响方面还考察得不多。本研究采用囚徒困境范式考察抑郁倾向对社会合作的影响。结果显示, 高抑郁倾向组比低抑郁倾向组的合作率更低, 双侧背外侧前额叶的激活更弱, 抑郁对右侧背外侧前额叶及眶额叶的脑间同步性有调节作用; 低抑郁被试与低抑郁被试配对时右侧颞顶联合区脑间同步性强于高抑郁被试与高抑郁被试配对, 或者高抑郁被试与低抑郁被试配对时的右侧颞顶联合区脑间同步性, 该效应当且仅当双方的选择相同时显著。结果表明, 抑郁群体在社会奖赏加工、冲突控制及心理理论脑区均存在功能性缺陷, 这些结果为理解抑郁人群合作意愿下降提供了脑成像证据。     

不同科学创造力个体干扰抑制机制的比较*

选取《科学创造力量表》筛选出高、低科学创造力个体各20名,通过完成经典Stroop色字干扰抑制任务,探讨高、低科学创造力的个体抑制机制的差异。结果发现:在Stroop色字任务上,无论是高科学创造力组还是低科学创造力组,都出现了Stroop干扰效应,但低科学创造力组的Stroop效应更明显;高科学创造力组在字色不一致条件下的错误率显著低于低科学创造力组,但是两组被试在Stroop任务反应时上差异不显著。本研究结果提示高科学创造力个体的认知抑制能力强于低科学创造力个体。     

汉语双字词在心理词典中的表征方式:来自fNIRS的证据

以汉语双字构成的真词与假词为实验材料,22名大学生为被试,采用功能性近红外脑成像技术(f NIRS)和事件相关设计,考察被试在完成词汇判断任务时的大脑激活模式,探索汉语双字词在心理词典中的表征方式。结果发现:(1)在完成真假词判断任务时,被试大脑左侧额叶和左侧颞叶均被激活;(2)与判断假词相比,被试在判断真词时显著地激活左额上回和左额中回。这一结果说明汉语双字词在心理词典中是混合表征的。     

Two-channel visual memory

Ss attempted immediate recall of word and color attributes of series of three “Stroop” words (Experiments I and 2) or three colored number words (Experiments 3 and 4), presented either at 2 words/sec or I word/2 sec. They were instructed to give either channel-by-channel recall, grouping words and colors together, or temporal recall, in which the two attributes of each item were to be reported together. In Experiments I and 3, in which words were to be reported before colors, channel-by-channel recall was rather better than temporal recall, especially at the fast rate. In Experiments 2 and 4, the colors were to be reported before the words, and channel-by-channel recall tended to be worse than temporal recall. In all four experiments serial position data suggested that the channel-by-channel strategy was to attend to one attribute (either words or colors) during presentation and hold the other in preattentive storage. By contrast, when instructed to give temporal report, Ss apparently alternated attention between attributes during presentation.     

The reverse Stroop effect

In classic Stroop interference, manual or oral identification of sensory colors presented as incongruent color words is delayed relative to simple color naming. In the experiment reported here, this effect was shown to all but disappear when the response was simply to point to a matching patch of color. Conversely, strong reverse Stroop interference occurred with the pointing task. That is, when the sensory color of a color word was incongruent with that word, responses to color words were delayed by an average of 69 msec relative to a word presented in gray. Thus, incongruently colored words interfere strongly with pointing to a color patch named by the words, but little interference from incongruent color words is found when the goal is to match the color of the word. These results suggest that Stroop effects arise from response compatibility of irrelevant information rather than automatic processing or habit strength.     

内侧颞叶系统在知觉启动中的作用及其机制

以ll例内侧颞叶(MTL)损伤病人为被试,探讨MTL与知觉启动的关系及其内在机制。被试依次完成学习颜色词、快速词命名和再认任务。在实验l的词命名中包括旧词、重组颜色词和新词,结果表明,MTL损伤病人没有表现出旧词的命名时间短于重组颜色词的现象,颜色启动效应受损,其再认成绩也低于正常被试。但是当用新颜色词代替重组颜色词后(实验2),MTL损伤病人读旧词的时间明显短于新颜色词,颜色启动与正常对照组之间没有明显差别,但他们的再认成绩仍比对照组低。这表明,当任务要求被试加工项目与其特性之间的关系时(词与颜色),MTL损伤对启动效应会有影响,提示MTL在一些形式的知觉启动中起重要作用。     

性别刻板印象表征的形式及神经基础

本实验采用ERP技术,考察性别刻板印象的表征。结果发现,无论启动是上位范畴、子范畴、典型样例还是反例,被试对于刻板印象不一致的表征比一致的表征均诱发了波幅更大的N400,反应时更长。并且,被试对于性别刻板印象的表征存在层级差异。研究结果表明：（1）性别刻板印象的表征存在层级结构。（2）语义启动下,性别刻板印象违背诱发N400效应。（3）性别刻板印象表征存在自上而下的由大脑额叶进行的语义分类加工。     

Verbal response-effect compatibility

Ideomotor theory states that motor responses are activated by an anticipation of their sensory effects. We assumed that anticipated effects would produce response-effect (R-E) compatibility when there is dimensional overlap of effects and responses. In a four-choice task, visual digit stimuli called for verbal responses (color names). Each response produced a written response-effect on the screen. In different groups, the response-effect was a colored color word (e.g., blue in blue), a white color word, or a colored nonword (Xs in blue). In different blocks, the predictable effects were either incompatible (e.g., response "blue" --> effect: green) or compatible with the response. We found faster responses with compatible than with incompatible R-E mappings. The compatibility effect was strongest with colored words, intermediate with white words, and smallest with colored nonwords. We conclude that effect anticipation influences response selection on both a perceptual level (related to the word's color) and a conceptual level (related to the word's meaning).     

Basic processes in reading: Is visual word recognition obligatory?

Visual word recognition is commonly argued to be automatic in the sense that it is obligatory and ballistic. The present experiments combined Stroop and visual search paradigms to provide a novel test of this claim. An array of three, five, or seven words including one colored target (a word in Experiments 1 and 2, a bar in Experiment 3) was presented to participants. An irrelevant color word also appeared in the display and was either integrated with or separated from the colored target. The participants classified the color of the single colored item in Experiments 1 and 3 and determined whether a target color was present or absent in Experiment 2. A Stroop effect was observed in Experiment 1 when the color word and the color target were integral, but not when the color word and the color target were separated. No Stroop effect was observed in Experiment 2. Visual word recognition is contingent on both the distribution of spatial attention and task demands.     

The nature of infant color categorization: evidence from eye movements on a target detection task

Infants respond categorically to color. However, the nature of infants' categorical responding to color is unclear. The current study investigated two issues. First, is infants' categorical responding more absolute than adults' categorical responding? That is, can infants discriminate two stimuli from the same color category? Second, is color categorization in infants truly perceptual? Color categorization was tested by recording adults' and infants' eye movements on a target detection task. In Experiment 1, adults were faster at fixating a colored target when it was presented on a colored background from a different color category (between-category) than when it was presented on a colored background from the same color category (within-category), even when within- and between-category chromatic differences were equated in CIE (Committee International d'Eclairage) color space. This category effect was found for two chromatic separation sizes. In Experiment 2, 4-month-olds also responded categorically on the task. Infants were able to fixate the target when the background color was from the same category. However, as with adults, infants were faster at fixating the target when the target background chromatic difference was between-category than when it was within-category. This implies that infant color categorization, like adult color categorization, is truly perceptual.     

Implicit processing of emotional words by children with Post-Traumatic Stress Disorder: An fMRI investigation

Background/ObjectiveIn the last decade, socio-political violence in Colombia (South America) has created an environment of extreme/chronic stress. In this study, brain imaging technology (fMRI) and behavioral task performance were used to measure potential deficits in executive functioning for emotional processing in Colombian children.MethodParticipants (22 Post-Traumatic Stress Disorder, PTSD and 22 neurotypical, NT) were asked to perform a word task with implicit emotional salience, which required them to report the color of the ink in which a positive, negative or neutral word was printed.ResultsMixed design analysis of variance showed no group differences in accuracy for determining ink color when presented as a positive or neutral word. However, PTSD children were significantly less accurate (negative words) and notably slower (both positive and negative words) at determining ink color when presented in the context of an emotional word. PTSD processing of positive and negative words was associated with hypoactivation in the superior and middle frontal gyri of the right hemisphere in comparison to NT children.ConclusionsThese results may reflect a deficit in executive functioning for emotionally laden stimuli, perhaps induced as a by-product of their traumatic experiences.     

The Extrinsic Affective Simon Task

A modified version of the Implicit Association Test (IAT) is described that is based on a comparison of performance on trials within a single task rather than on a comparison of performance on different tasks. In two experiments, participants saw white words that needed to be classified on the basis of stimulus valence and colored words that were to be classified on the basis of color. On trials where the colored word referred to a positive target concept (e.g., "flowers," "self"), performance was superior when the correct response was the response that was also assigned to positive white words. The reverse was true on trials where the colored word represented a negative target concept (e.g., "insect"). This variant of the IAT is less susceptible to nonassociative effects of task recoding and can be used to assess single and multiple attitudes.