整体/局部加工中的半球功能不对称效应

20世纪末的研究证据显示,对Navon等级刺激的整体/局部加工中半球功能不对称效应发生在早期还是晚期阶段,研究者存在着争论。近期的电生理和功能成像研究资料表明,整体/局部加工的半球不对称效应可能是一个受到多种因素调节的复杂动态系统;早期信息表征的半球功能不对称效应可能主要受知觉因素的影响,而注意控制和反应冲突可能主要调节晚期知觉加工的半球功能不对称     

大脑及肢体的不对称功能

人体的外观，看起来是左右对称的，但人体的内部组织结构和功能则有很多地方是不对称的，这种不对称实例的首选是人的大脑。绝大多数人的大脑左侧为优势半球，即绝大多数人都是大脑左侧半球掌管着逻辑思维和抽象思维，即掌管着语言功能。因此，大脑左侧半球有“语言脑”之...     

社会创造性的脑机制:状态与特质的EEGα波活动特点

采用社会问题情境,通过记录38名高、低特质社会创造性被试在社会问题解决过程中的脑电活动,考查不同特质社会创造性的被试在表现不同状态社会创造性时的脑电激活模式。结果表明:无论高频还是低频α波同步化都存在状态创造性的主效应。同时,高、低频段的α波同步化还存在特质创造性与状态创造性之间显著的交互作用,在表现高状态社会创造性时,高特质的被试比低特质的被试出现更高的α波同步化水平。此外,对于高频α波同步化,状态创造性、特质创造性以及大脑半球的三重交互作用达到显著性水平,低特质社会创造性的被试在表现高状态社会创造性时,右脑半球比左脑半球出现更强烈的α波同步化,在其他情况下均无显著差异。未来的研究可以采用时间进程分析、纵向研究设计、脑功能成像技术探查社会创造性的脑机制。     

时间的多维度空间表征:分离的起源与激活机制

近期研究发现时间可以分别在三个空间维度(左右、前后和上下)进行表征, 但不同维度心理时间线的起源和激活机制尚存争议。最新证据表明, 左右维度时间线主要起源于阅读/书写习惯所伴随的感觉运动经验, 其激活可能是一种低水平的感觉运动机制; 前后和上下维度时间线主要起源于语言中的空间隐喻, 其激活可能是一种高水平的语义机制。未来研究应更关注心理时间线的起源多样性、先天基础、神经机制以及时间线和数字线的类比。     

小而灵通，老而顽固？年龄信息对创造性观念评价的影响及其机制

创作者的年龄作为重要的社会线索信息,可能会影响大众对其观点的创造性评价。本研究以物品非常规用途想法作为评价材料,考察了4类年龄信息对创造性观念评价的影响,以及相关刻板印象在其中的作用。结果发现,10岁左右年龄信息会提升被试的新颖性和适用性评分;30岁左右的信息提升了新颖性评分,但刻板印象强弱对评分变化不具有预测作用。这表明,对于领域一般性产品,有关创作者的刻板印象不易被激活并应用于创造性评价。     

言语产生老化中的抑制损伤:来自不同任务的证据

通过3个实验,探讨干扰抑制在言语产生老化中的作用。实验1采用经典Stroop任务,发现老年人在高水平的、自动的语义激活时产生了更大的抑制困难。实验2操纵潜在竞争词的语义激活水平,发现在潜在竞争词处于低水平的语义激活时,老年人的抑制能力与年轻人相当;在潜在竞争词处于高水平的语义激活时,老年人表现出抑制能力的劣势。实验3采用造句任务,发现老年人在抑制角色冲突时存在着较大的困难,老年人在顺序不一致的条件下的造句成绩显著差于年轻人。整个研究表明,老年人在言语产生中的抑制能力差于年轻人,但抑制老化效应受潜在干扰刺激的激活水平影响。     

语义选择的半球机制研究

从刺激呈现时可能伴随的许多激活的亚信息中选择出某种意义以整合前文的半球机制是个值得研究的问题,有关研究正逐步增多。     

社会动机与“自我-他人”对创造性表现的影响

以往研究发现个体为自己和为他人的创造表现存在差异,但研究结论不一致。另外,考虑到社会动机是影响“自我-他人”表现的重要因素,本研究采用2（社会动机：亲社会、利己）×2（“自我-他人”：自我、他人）混合实验设计,考察社会动机与“自我-他人”如何来影响创造性表现。结果发现,亲社会组创造性表现的新颖性、有效性和总分均高于利己组,支持了动机性信息加工理论。自我组在创造性表现的新颖性和总分上高于他人组,这与解释水平理论的观点不一致。矛盾的原因可能是在东方“紧”文化背景下,人们按照社会认可的价值体系来为他人创造时,人们对新颖性的态度是谨慎的,因此为自我创造比为他人创造更加新颖。     

跨语言启动的不对称性现象及其理论解释的新进展

该文重点介绍了跨语言掩蔽启动不对称性现象及其新的理论解释一意义模型.意义模型认为目标词中已经激活词义数目与完全激活该词需要的词义数目的比率决定着跨语言启动不对称现象的产生.目前意义模型较好地解释跨语言启动不对称现象,但仍有许多问题需要进一步的研究.     

创造性倾向对科学问题解决中原型位置效应的影响*

以科学发明创造题目为实验材料,采用“一对一”的实验范式,对创造性问题解决中的创造性倾向与原型位置效应的关系进行了探讨,实验考察了不同创造性倾向个体在创造性问题解决中的原型位置效应,创造性倾向包括想象力、冒险性、好奇性、挑战性四个因素,结果发现:创造性倾向总分、好奇性、挑战性对原型位置效应有影响,而且原型位置效应随着创造性倾向、好奇性、挑战性的降低而显著;想象力、冒险性对原型位置效应的影响不显著。     

Emotional Television Scenes and Hemispheric Specialization

This study examined hemispheric differences¹ in cortical arousal as a function of positive and negative emotional television scenes. A three-factor within-subjects design was used: hemispheres (right and left), location of cortical arousal (frontal and occipital), and emotional content of messages (positive and negative). Based on findings that the frontal cortex responds differently to emotional stimuli, it was predicted that negative television content would produce greater right hemisphere activity, and that positive content would produce greater left hemisphere activity, but that differences would be apparent only in the frontal region. The results confirmed these predictions. There was a significant interaction between hemisphere and emotional content for frontal alpha, but no interaction for occipital alpha.² There were two other main effects: (1) greater cortical arousal for negative than positive scenes, and (2) greater occipital than frontal arousal. The results are discussed in relation to a definition of emotional scenes that emphasizes approach (positive emotion) versus withdrawal (negative emotion), and in relation to hemispheric specialization and the ability of television to prime overt behavior.     

Hemispheric asymmetry in the processing of negative and positive words: A divided field study

Research on the lateralisation of brain functions for emotion has yielded different results as a function of whether it is the experience, expression, or perceptual processing of emotion that is examined. Further, for the perception of emotion there appear to be differences between the processing of verbal and nonverbal stimuli. The present research examined the hemispheric asymmetry in the processing of verbal stimuli varying in emotional valence. Participants performed a lexical decision task for words varying in affective valence (but equated in terms of arousal) that were presented briefly to the right or left visual field. Participants were significantly faster at recognising positive words presented to the right visual field/left hemisphere. This pattern did not occur for negative words (and was reversed for high arousal negative words). These results suggest that the processing of verbal stimuli varying in emotional valence tends to parallel hemispheric asymmetry in the experience of emotion.     

Hemispheric asymmetry in the processing of negative and positive words: a divided field study

Research on the lateralisation of brain functions for emotion has yielded different results as a function of whether it is the experience, expression, or perceptual processing of emotion that is examined. Further, for the perception of emotion there appear to be differences between the processing of verbal and nonverbal stimuli. The present research examined the hemispheric asymmetry in the processing of verbal stimuli varying in emotional valence. Participants performed a lexical decision task for words varying in affective valence (but equated in terms of arousal) that were presented briefly to the right or left visual field. Participants were significantly faster at recognising positive words presented to the right visual field/left hemisphere. This pattern did not occur for negative words (and was reversed for high arousal negative words). These results suggest that the processing of verbal stimuli varying in emotional valence tends to parallel hemispheric asymmetry in the experience of emotion.     

A comparison of hemispheric asymmetries in speech-related brain potentials of autistic and dysphasic children

In a previous study (G. Dawson, C. Finley, S. Phillips, & L. Galpert, 1986, Child Development, 57, 1440-1453) it was found that measures of hemispheric asymmetry during speech processing were predictive of level of language ability in autistic children. The purpose of the present study was to determine whether a similar relationship between pattern of hemispheric asymmetry and language ability exists for language-impaired children without autism. Ten autistic children (8-13 years), 10 dysphasic children (6-15 years), and 10 normal children (8-13 years) were compared in terms of their patterns of hemispheric asymmetry in the averaged cortical evoked response to a simple speech stimulus, and the relationship between pattern of hemispheric asymmetry and language ability was assessed for each clinical group. It was found that, for both the autistic and dysphasic groups, the majority of subjects showed a reversed direction of hemispheric asymmetry from that characteristic of the normal group. A strong relationship between pattern of asymmetry and level of language ability was found for autistic subjects; autistic subjects with more severe language impairments were more likely to show reversed asymmetry than subjects with less severe language impairments. In contrast, no relationship between language ability and direction of hemispheric asymmetry in the evoked response was found for dysphasic subjects. Separate analyses of right and left hemisphere evoked responses indicated that language ability was related to right hemisphere activity for autistic subjects, and to left hemisphere activity for dysphasic subjects.     

Effect of short lateralized signals on arousal versus activation on tasks requiring visuospatial or elementary semantic stimulus processing

The results of the experiment offer indirect evidence for the basic hypothesis that the brain self-regulates its own arousal and activation as a function of the intensity and type of ongoing cortical activity. When subjects perform a task which can be assumed to be primarily attended to by the right hemisphere, the result of a supplementary information-processing load seems to be increased arousal. On a task primarily attended to by the left hemisphere, the consequence is increased activation. The evidence is indirect because no measurements have been made of the neurological events and processes which are assumed to intervene in this self-regulation process. Although indirect, the evidence may help to formulate more precise psychological hypotheses about the factors controlling the putative effort system which, according to Pribram and McGuinness in 1975, coordinates the arousal and activation of cerebral processes.     

Alteration of expected hemispheric asymmetries: valence and arousal effects in neuropsychological models of emotion

The relative advantage of the left (LH) over the right hemisphere (RH) in processing of verbal material for most individuals is well established. Nevertheless, several studies have reported the ability of positively and negatively valenced stimuli to enhance and reverse, respectively, the usual LH>RH asymmetry. These studies, however, have used baseline stimuli that differed from emotional stimuli on two dimensions (i.e., valence and verbal/nonverbal nature), creating interpretive difficulties as to whether differences across these conditions are due to differences in valence or the verbal/nonverbal nature of the primes used in the baseline condition. In addition, these studies, along with many others in the literature, have failed to control for potential confounding effects of arousal. Emotional stimuli vary on dimensions of valence as well as arousal and arousal may be asymmetrically presented in the brain therefore contributing to observed asymmetries. Taken together, these considerations underscore the importance of controlling for both valence as well as arousal in any investigation of the effects of emotional stimuli. The objectives of the present study were twofold: (1) to employ an appropriate baseline condition to render emotional stimuli vs. baseline stimuli comparisons meaningful and (2) to examine the extent to which emotional verbal stimuli, equated for arousal level, alter the expected LH>RH asymmetry in a consonant trigram task. Results demonstrated that when LH lateralized consonant trigram presentations were preceded by a positive prime, an enhancement of the expected LH>RH asymmetry was observed. In contrast, when trigram presentations lateralized to the RH were preceded by a negative prime, a complete reversal of the typical asymmetry was found with RH>LH performance. These results are analogous to the pattern of relative hemispheric activations observed for various mood states. Controlling for arousal in studies investigating asymmetries associated with emotional processing may allow more clear interpretation of data intended to test predictions of neuropsychological models of emotion. Moreover, equating stimuli on the dimension of arousal as well as valence may shed more light on conflicting findings with regard to perception vs. expression of emotion.     

Hemispheric asymmetry in cross-race face recognition

This study examines two phenomena related to face perception, both of which depend on experience and holistic processing: perceivers process faces more efficiently in the right hemisphere of the brain (a hemispheric asymmetry), and they typically show greater recognition accuracy for members of their racial ingroup (a cross-race recognition deficit). The current study tests the possibility that these two effects are related. If asymmetry depends on experience, it should be particularly evident with (more familiar) ingroup faces; if cross-race recognition relies on holistic processing, it should be particularly evident for faces presented to the right hemisphere. Black and White participants viewed Black and White faces presented to either the left or right visual field. As predicted, participants showed a more pronounced asymmetry for ingroup (rather than outgroup) faces, and cross-race recognition deficits were more pronounced for stimuli presented to the left (rather than the right) visual field.     

Face recognition: a general or specific right hemisphere capacity?

Face-recognition ability has been claimed to be qualitatively different from other pattern-recognition abilities. One argument for this claim is the finding of a significant right hemisphere advantage for the recognition of upright but not inverted faces. However, this argument is justified only if this orientation-sensitive pattern is unique to faces. In the present study, comparable patterns of orientation-sensitive involvement of the right hemisphere are found for the recognition of faces and houses. This finding is interpreted as evidence for a right hemisphere schema formation capacity that is applied not only to upright faces but also to other familiar classes of stimuli in their canonical upright orientation. It is suggested that any greater right hemisphere involvement in the recognition of upright faces is due to our greater expertise at recognizing faces than other stimulus types. We also find evidence that only a subset of right-handed adults show orientation-sensitive right hemisphere involvement in the recognition of faces and houses: in particular, those dextrals with a characteristic hemispheric arousal asymmetry in favor of the right hemisphere. In contrast, dextrals with a characteristic arousal asymmetry in favor of the left hemisphere do not show significant visual field asymmetries for faces or houses in either upright or inverted orientations.     

Musicians processing music: Measurement of brain potentials with EEG

Abstract

In the present study, the EEG was recorded from the scalp of musicians while mentally active in their field. Analytic, creative and memory processes of the brain were observable using a special electrophysiological method called DC-potential recording. Music students listened to a sequence of four notes and subsequently were either to reverse the sequence (task 1 = analytic) or to compose a new continuation (task 2 = creative). In task 3, the initial segment of a well-known melody was presented and had to be continued (memory task). All tasks had to be solved mentally (imagery). In tasks 1 and 2, either tonal or atonal sequences were presented.

While processing, the results show that the analytic task elicited the highest brain activity. The analytic task involved mainly parieto-temporal areas of both hemispheres, the left hemisphere showing a tendency for domination. The memory task produced predominant activity over the right hemisphere. The creative task caused the lowest brain activation and elicited an unexpected lateralisation to the left, though we expected creativity to be a right hemispheric holistic-synthetic phenomenon.

Comparing listening with processing of the perceived music, we found a significant shift from an insignificant right hemispheric to an insignificant left hemispheric predominance (except with the memory task). This indicates that musicians do not lateralise to the left hemisphere per se when listening to music. Whether one finds a left hemispheric lateralisation in listening tasks or a right hemispheric one probably depends on the amount of simultaneous analytic-sequential processing the musician undertakes.