Role of amygdala-prefrontal cortex circuitry in regulating the expression of contextual fear memory

The basolateral amygdala (BLA) and medial prefrontal cortex (mPFC) are inter-connected regions involved in fear memory expression. The reciprocal nature of projections between these areas differs along the rostrocaudal extent of BLA. This study investigated the role of functional interactions between BLA and the prelimbic (PL) subregion of mPFC in mediating contextual fear memory. Freezing served as the measure of conditioned fear. Experiments 1–3 examined the effects of left, right or bilateral infusion of bupivacaine into anterior BLA (aBLA), posterior BLA (pBLA) or PL on fear memory expression. Reversible inactivation of left, right or bilateral aBLA impaired fear memory expression. Bilateral inactivation of pBLA or PL also disrupted the expression of fear memory, although left or right inactivation alone had no significant effects in either region. Experiment 4 examined the effects of functionally disconnecting pBLA and PL on contextual fear memory by infusing bupivacaine unilaterally into pBLA and PL in the ipsilateral or contralateral hemisphere. Fear memory expression was impaired by asymmetric inactivation of pBLA and PL; however, a similar effect was also observed with symmetric inactivation of these regions. Bupivacaine infusion did not affect behavior in the open field, likely ruling out non-specific effects of inactivation on innate fear and locomotor activity. These results demonstrate different roles for rostral and caudal BLA in mediating the expression of contextual fear memory. They also raise the possibility that pBLA–PL circuitry is involved in subserving fear memory expression via complex processing mechanisms, although further research is needed to confirm this preliminary finding.     

Suicide bombings and the self

The failure to locate a unifying psychological profile of suicide bombers should prompt moves to a more extended and interdisciplinary front, availing itself of insights from disciplines such as sociology, philosophy and history of ideas, as well as from psychology. This paper aims in that direction by exploring ‘traditional’ versus ‘western liberal’ conceptions of the self, with special emphasis on their possible pathologies; and by integrating those pathologies with insights from Durkheimian suicidology. It is hypothesised that suicide bombers in the West are typically callow, malleable young men targeted by terror merchants, and that their suicide missions are, first and foremost, acts of deluded self-enhancement, which need to be understood against the backdrop of the western liberal conception of the self. Finally, some implications for moral education are suggested.     

Self-construal priming modulates the scope of visual attention

Although it is well documented that cultures influence basic cognitive processes such as attention, the underlying mechanisms remain unclear. We tested the hypothesis that self-concepts that characterize people from different cultures mediate the variation of visual attention. After being primed with self-construals that emphasize the Eastern interdependent self or the Western independent self, Chinese participants were asked to discriminate a central target letter flanked by compatible or incompatible stimuli (Experiment 1) or global/local letters in a compound stimulus (Experiment 2). Experiment 1 showed that, while responses were slower to the incompatible than to the compatible stimuli, this flanker compatibility effect was increased by the interdependent relative to the independent self-construal priming. Experiment 2 showed that the interdependent-self priming resulted in faster responses to the global than to the local targets in compound letters whereas a reverse pattern was observed in the independent-self priming condition. The results provide evidence for dynamics of the scope of visual attention as a function of self-construal priming that switches self-concept toward the interdependent or independent styles in Chinese.     

The relationship between allocentric and egocentric frames of reference and categorical and coordinate spatial information processing

We report two experiments on the relationship between allocentric/egocentric frames of reference and categorical/coordinate spatial relations. Jager and Postma (2003) suggest two theoretical possibilities about their relationship: categorical judgements are better when combined with an allocentric reference frame and coordinate judgements with an egocentric reference frame (interaction hypothesis); allocentric/egocentric and categorical/coordinate form independent dimensions (independence hypothesis). Participants saw stimuli comprising two vertical bars (targets), one above and the other below a horizontal bar. They had to judge whether the targets appeared on the same side (categorical) or at the same distance (coordinate) with respect either to their body-midline (egocentric) or to the centre of the horizontal bar (allocentric). The results from Experiment 1 showed a facilitation in the allocentric and categorical conditions. In line with the independence hypothesis, no interaction effect emerged. To see whether the results were affected by the visual salience of the stimuli, in Experiment 2 the luminance of the horizontal bar was reduced. As a consequence, a significant interaction effect emerged indicating that categorical judgements were more accurate than coordinate ones, and especially so in the allocentric condition. Furthermore, egocentric judgements were as accurate as allocentric ones with a specific improvement when combined with coordinate spatial relations. The data from Experiment 2 showed that the visual salience of stimuli affected the relationship between allocentric/egocentric and categorical/coordinate dimensions. This suggests that the emergence of a selective interaction between the two dimensions may be modulated by the characteristics of the task.     

False recall in the Deese–Roediger–McDermott paradigm: The roles of gist and associative strength

Theories of false memories, particularly in the Deese–Roediger–McDermott (DRM) paradigm, focus on word association strength and gist. Backward associative strength (BAS) is a strong predictor of false recall in this paradigm. However, other than being defined as a measure of association between studied list words and falsely recalled nonpresented critical words, there is little understanding of this variable. In Experiment 1, we used a knowledge-type taxonomy to classify the semantic relations in DRM stimuli. These knowledge types predicted false-recall probability, as well as BAS itself, with the most important being situation features, synonyms, and taxonomic relations. In three subsequent experiments, we demonstrated that lists composed solely of situation features can elicit a gist and produce false memories, particularly when monitoring processes are made more difficult. Our results identify the semantic factors that underlie BAS and suggest how considering semantic relations leads to a better understanding of gist formation.     

The fate of being forgotten: Information that is initially forgotten is judged as less important

Is forgotten information deemed less important than remembered information? The present study examined potential biases regarding the importance of information that was initially forgotten. In Experiment 1 participants studied words paired with varying point values that denoted their importance and were encouraged to recall higher value words. Participants recalled more high-value words on an initial test. However, on a later cued recall test for the values, initially forgotten words were rated as less valuable than remembered words. Experiment 2 used a similar procedure with the exception that participants rated the importance of traits when evaluating a significant other (e.g., honest, intelligent). Participants were more likely to recall highly valued traits but regarded forgotten traits as less valuable than remembered traits. These results suggest that a forgetting bias exists: If information is initially forgotten, it is later deemed as less important.     

清代学者焦循独特的易学构架

本文考述了焦循的旁通、相错、时行三说,并在此基础之上提出了一系列看法：1．焦循以普遍联系和爻位运动的观点研究《周易》,把《周易》六十四卦视为具有内在联系的“生生不息”的动态系统,比之孤立、静止地研究《周易》一卦一爻,更有意义。2．焦循独特的易学构架是建立在客观分析的考据基础之上,不宜武断否定。3．焦循易学构架并非纯象数的研究,而是以象数为载体,阐发儒家的道德义理和自己“修齐治平”的政治理想。4．焦循以“声训”为媒介的两卦或数卦之间的关联是否《周易》本义值得讨论,其“声训”缺乏充分的文献旁证是一大缺憾。     

创业环境与大学生创业意向的关系:有调节的中介模型

本研究提出一个有调节的中介模型,揭示了创业环境"怎样"影响大学生创业意向及这种影响"何时"更强或更弱。采用创业环境量表、创业动机量表、创业意向量表对647名大学生进行研究。研究显示:(1)创业动机在创业环境与大学生创业意向之间起部分中介作用;(2)性别调节了创业环境通过创业动机影响大学生创业意向的中介过程的前半路径。因此,创业环境对大学生创业意向的影响是有调节的中介效应,研究结论对提高大学生的创业意向具有重要的理论与实证价值。