The neural basis of cognitive control: Response selection and inhibition

The functional neuroanatomy of tasks that recruit different forms of response selection and inhibition has to our knowledge, never been directly addressed in a single fMRI study using similar stimulus–response paradigms where differences between scanning time and sequence, stimuli, and experimenter instructions were minimized. Twelve right-handed participants were scanned on two standard cognitive control tasks, a stimulus–response incompatibility task, and a response inhibition task. A compound trial design allowed comparison of preparing to inhibit an upcoming automatic response to wholly inhibiting an automatic response. Furthermore, inhibiting an automatic response to perform an alternative task-relevant response was compared to wholly inhibiting an automatic response. No differences were found in prefrontal activity when preparing to inhibit an automatic response was compared to wholly inhibiting an automatic response, suggesting a mostly common network. The left inferior frontal gyrus was found to be commonly recruited during both tasks when controlled responses were required, likely due to its role in response selection. In contrast, the right inferior frontal gyrus was found to be more involved when task demands were stronger for response inhibition. Our results are largely consistent with models of cognitive control that postulate that separate psychological constructs, such as response selection and inhibition, are related processes largely served by a common prefrontal network. This prefrontal network is recruited to a greater or lesser extent depending on specific task demands.     

Self-referential processing of negative stimuli within the ventral anterior cingulate gyrus and right amygdala

Neural activity associated with self-referential processing of emotional stimuli was investigated using whole brain functional magnetic resonance imaging (fMRI). Fifteen healthy subjects underwent fMRI scanning while making judgments about positive and negative trait words in four conditions (self-reference, other-reference, semantic processing, and letter processing). Significant activity was observed in the right ventral anterior cingulate gyrus and the right amygdala in the negative-word/self-reference condition, and in the left amygdala in the positive-word/self-reference condition. Compared with the semantic-processing condition, the self-reference conditions showed significantly more activity in the medial prefrontal and temporal gyri, posterior cingulate gyrus, and precuneus. These results suggest that the medial prefrontal gyrus, posterior cingulate gyrus, and precuneus are associated with a self-referential processing, and the ventral anterior cingulate gyrus is involved in self-referential processing of negative emotional stimuli. The results also suggest that the amygdala is associated with self-referential processing of both positive and negative emotional stimuli.     

选择扩散效应研究的回顾与前瞻

由失调导致的态度改变一直受到社会心理学的关注,选择扩散效应是态度改变的结果之一。多个理论模型对此做出各种解释,近年来对失调的脑机制研究为行为模型提供了新的证据。文化心理学也涉足了这方面的研究,并多以自我模型为基础,发现东西方人在对失调的体验及随后的态度变化上存在文化差异。总结了选择扩散效应的研究意义后,文章从该效应的研究范式、心理机制和脑机制、文化影响三方面对相关研究进行回顾,在此基础上提出研究范式的区分、模型的整合、脑机制的进一步研究、减缓失调的积极作用是未来的研究趋势,并指出跨文化研究中应注意的问题     

联觉的认知神经机制

联觉是指由一种感官刺激引起其他感官体验的心理过程。近年来的研究将行为实验和脑成像技术结合,发现了联觉的认知神经基础。本文总结了最受关注的字形-颜色联觉的研究成果,认为联觉发生在视知觉加工的早期阶段,与知觉在本质上有许多共同特征,其脑区涉及梭状回（V4）和顶叶。未来联觉的研究将通过综合运用各种方法,进一步拓宽研究范围。     

The expression of c-Fos and colocalisation of c-Fos and glucocorticoid receptors in brain structures of low and high anxiety rats subjected to extinction trials and re-learning of a conditioned fear response

We designed an animal model to examine the mechanisms of differences in individual responses to aversive stimuli. We used the rat freezing response in the context fear test as a discriminating variable: low responders (LR) were defined as rats with a duration of freezing response one standard error or more below the mean value, and high responders (HR) were defined as rats with a duration of freezing response one standard error or more above the mean value. We sought to determine the colocalisation of c-Fos and glucocorticoid receptors-immunoreactivity (GR-ir) in HR and LR rats subjected to conditioned fear training, two extinction sessions and re-learning of a conditioned fear. We found that HR animals showed a marked decrease in conditioned fear in the course of two extinction sessions (16 days) in comparison with the control and LR groups. The LR group exhibited higher activity in the cortical M2 and prelimbic areas (c-Fos) and had an increased number of cells co-expressing c-Fos and GR-ir in the M2 and medial orbital cortex after re-learning a contextual fear. HR rats showed increased expression of c-Fos, GR-ir and c-Fos/GR-ir colocalised neurons in the basolateral amygdala and enhanced c-Fos and GR-ir in the dentate gyrus (DG) in comparison with LR animals. Our data indicate that recovery of a context-related behaviour upon re-learning of contextual fear is accompanied in HR animals by a selective increase in c-Fos expression and GRs-ir in the DG area of the hippocampus.     

The right parahippocampal gyrus contributes to the formation and maintenance of bound information in working memory

Working memory is devoted to the temporary storage and on-line manipulation of information. Recently, an integrative system termed the episodic buffer has been proposed to integrate and hold information being entered or retrieved from episodic memory. Although the brain system supporting such an integrative buffer is still in debate, the medial temporal lobe appears to be a promising candidate for the maintenance of bound information. In the current work, binding was assessed by comparing two conditions in which participants had to retain three letters and three spatial locations presented either bound or separate. At the behavioral level, lower performance was found for bound information than for separate information. When contrasting the two conditions, activation in the right parahippocampal gyrus was greater for the encoding and maintenance of bound information. No activation was observed in the medial temporal lobe during the retrieval of bound information. Together, our results suggest that the parahippocampal gyrus may underlie the integrative and maintenance functions of the episodic buffer.     

不同留守时间下儿童公正感的特点及其与主观幸福感的关系

采用公正感问卷,生活满意度问卷和积极/消极情感问卷,选取5-8年级565名留守儿童和640名非留守儿童进行调查,探讨不同留守时间下儿童公正感的特点及其与主观幸福感(生活满意度,积极情感,消极情感)的关系。结果表明:(1)不同留守时间下,儿童的公正感得分存在边缘显著性差异(p=0.055);(2)总体上,留守儿童的公正感得分显著低于非留守儿童。具体讲,留守4年半以下和4年半～10年,儿童的公正感得分均显著低于非留守儿童;留守10年以上的儿童公正感得分和非留守儿童不存在差异;(3)各留守时间下,公正感对于生活满意度、积极情感均具有显著地正向预测作用,但对于消极情感仅在特定时间具有显著负向预测作用。表明,留守时间是影响儿童公正感特点及其和主观幸福感关系的重要因素。     

高血压左室肥厚的QT离散度及左室Tei指数的关系探讨

心脏是最常见的高血压损伤靶器官,首先引起左心室肥厚,然后导致心功能下降,并可导致心律失常。高血压患者中约有1/3会出现左室肥厚（LVH）,可致心血管病事件发病率增加,病死率升高,是猝死、冠心病和充血性心力衰竭的独立的、主要的危险因素和预后信号。QT间期离散度（QTd）是反映心室肌复极的不均匀性和电不稳定性预测恶性室性心...     

Individual differences in skilled adult readers reveal dissociable patterns of neural activity associated with component processes of reading

We used fMRI to examine patterns of brain activity associated with component processes of visual word recognition and their relationships to individual differences in reading skill. We manipulated both the judgments adults made on written stimuli and the characteristics of the stimuli. Phonological processing led to activation in left inferior frontal and temporal regions whereas semantic processing was associated with bilateral middle frontal activation. Individual differences in reading subskills were reflected in differences in the degree to which cortical regions were engaged during reading. Variation in sight word reading efficiency was associated with degree of activation in visual cortex. Increased phonological decoding skill was associated with greater activation in left temporo-parietal cortex. Greater reading comprehension ability was associated with decreased activation in anterior cingulate and temporal regions. Notably, associations between reading ability and neural activation indicate that brain/behavior relationships among skilled readers differ from patterns associated with dyslexia and reading development.     

左利手及其形成机制:生理、病理及心理学的视角

与右利手相比,左利手在人口中占少数,并且具有明显的性别差异,男性比女性多。左利手有时会表现出认知缺陷,同时在某些领域也具有优势。左利手形成机制比较复杂,既有遗传影响,也有生理、病理方面的原因,可能的因素包括早期脑损伤,各种出生风险因素,以及孕期激素水平等,还具有深刻的心理、社会根源。