冲动-思考型儿童在拼图游戏中的问题解决及元认知差异

以小学六年级思考型和冲动型儿童各32名为被试,通过考查儿童在完成不同难度拼图任务时的表现,探讨不同认知风格儿童在问题解决中认知活动和元认知活动的差异。结果发现:(1)在线与离线元认知监控均表现出认知风格与任务难度的交互作用。在简单和中等任务中,思考型的儿童运用更多的在线元认知监控,进行计划和检查的时间更长。离线元认知监控的差异只表现在简单任务中,思考型比冲动型儿童花费更多的时间进行预测和评价;(2)在问题解决结果上,认知风格不同的儿童完成任务的时间没有显著差异;(3)在问题解决过程中,冲动型儿童解决问题的操作步数多于思考型儿童;冲动型儿童更多地使用主体参照策略,而思考型儿童更多使用线索推断策略。     

颈动脉病变的治疗现状

颈动脉病变尤其是颈动脉狭窄治疗上的分歧,颈动脉内膜切除术受欧美学者推崇,颈动脉支架成形技术受国内学者青睐,本文就近年来的文献复习发现颈动脉内膜切除术和颈动脉支架成形术各有相宜的适应证,各有优缺点,根据各自医院的设备条件、医师对颈动脉内膜切除术和颈动脉支架成形术熟悉程度来开展工作,对颈动脉狭窄治疗均有益处,存在的问题和困...     

Basolateral amygdala inactivation impairs learned (but not innate) fear response in rats

Numerous studies have suggested that the amygdala is involved in the formation of aversive memories, but the possibility that this structure is merely related to any kind of fear sensation or response could not be ruled out in previous studies. The present study investigated the effects of bilateral inactivation of the amygdaloid complex in rats tested in the plus-maze discriminative avoidance task. This task concomitantly evaluates aversive memory (by discrimination of the two enclosed arms) and innate fear (by open-arm exploration). Wistar rats (3-5 months-old) were implanted with bilateral guide cannulae into basolateral amygdala. After surgery, all subjects were given 1 week to recover before behavioral experiments. Afterwards, in experiment 1, 15 min prior to training, 0.5 μl of saline or muscimol (1 mg/ml) was infused in each side via microinjection needles. In experiment 2 the animals received injections immediately after the training session and in experiment 3 rats were injected prior to testing session (24 h after training). The main results showed that (1) pre-training muscimol prevented memory retention (evaluated by aversive arm exploration in the test session), but did not alter innate fear (evaluated by percent time in open arms); (2) post-training muscimol impaired consolidation, inducing increased percent in aversive arm exploration in the test session and (3) pre-testing muscimol did not affect retrieval (evaluated by aversive enclosed arm exploration in the test session). The results suggest that amygdala inactivation specifically modulated the learning of the aversive task, excluding a possible secondary effect of amygdala inactivation on general fear responses. Additionally, our data corroborate the hypothesis that basolateral amygdala is not the specific site of storage of aversive memories, since retention of the previously learned task was not affected by pre-testing inactivation.     

Re-emergence of extinguished auditory-cued conditioned fear following a sub-conditioning procedure: effects of hippocampal and prefrontal tetanic stimulations

Post-extinction exposure of rats to a sub-conditioning procedure can evoke conditioned fear, which may correspond to fear return and/or fear learning potentiation. The aim of the present study was to clarify this issue and examine the effects of tetanic stimulation of the hippocampus (HPC) and medial prefrontal cortex (mPFC), two brain regions implicated in post-extinction modulation of conditioned fear. Rats were initially submitted to five tone-shock pairings with either a 0.7-mA or 0.1-mA shock. Tone-evoked freezing was observed only with the higher shock intensity, indicating that the 0.1-mA shock corresponded to a sub-conditioning procedure. All conditioned rats underwent fear extinction with 20 tone-alone trials. When retrained with the sub-conditioning procedure, they displayed again tone-evoked freezing, except when the initial tone was unpaired or a new tone was paired with the 0.1-mA shock, demonstrating fear return rather than fear learning potentiation. We also found that HPC and mPFC tetanic stimulations, applied 24h after the sub-conditioning procedure, similarly reduced this fear return. However, mPFC inactivation abolished temporary HPC tetanus effect, whereas HPC inactivation did not interfere with mPFC tetanus effect. These data confirm our previous findings and reveal the nature of HPC-mPFC interactions in post-extinction modulation of conditioned fear.     

Pre-training anandamide infusion within the basolateral amygdala impairs plus-maze discriminative avoidance task in rats

Endocannabinoids (eCBs) modulate a variety of brain functions via activation of the widely expressed CB1 receptor. One site of high density of this receptor is the basolateral amygdala (BLA), a structure involved in the formation of aversive memories. The activation and blockade of CB1 receptors by systemic or hippocampal drug administrations have been shown to modify memory processing. However, little is known about the role of the BLA endocannabinoid system in aversive memories. Additionally, BLA endocannabinoid transmission seems to be related to emotional states, but the relevance of these effects to memory formation is still unknown. In this study we investigated the effects of the eCB anandamide (AEA) and the CB1 antagonist/inverse agonist AM251 infused into the BLA on the acquisition of an aversive memory task, concomitantly evaluating basal anxiety levels in rats. Male rats received pre-training micro-injection of AEA, AM251 or vehicle bilaterally into the BLA, and were studied with the plus-maze discriminative avoidance task (a paradigm that allows concomitant and independent evaluation of anxiety-like behavior and the memory of an aversive task). Our results showed that AEA into the BLA before training prevented memory retrieval 24 h later, as evaluated by exploration of the aversive arm of the maze, while AM251 into the BLA did not interfere with animals' performance. In addition, AEA had no effect on anxiety-like behavior (as evaluated by open arm exploration and risk assessment), while AM251 induced an anxiogenic effect. Our data indicate an important role of BLA CB1 receptors in aversive memory formation, and suggest that this involvement is not necessarily related to a possible modulation of anxiety states.     

Beliefs and preferences in cultural agents and cultural game players

Two laboratory experiments demonstrated that Japanese participants did not conform to the majority unless negative social implications of not conforming were clear. When their behaviour had no implications for others, they rather exhibited preference for uniqueness. Results of Study 2 further demonstrated that participants' conformity to the majority was particularly prevalent among those who were chronically concerned with how other people would perceive them. Participants in these studies were shown to be cultural game players who changed their behaviour in response to anticipated responses of others based on culturally shared beliefs.     

青年颈心综合征避免误诊为冠心病的临床诊疗策略

通过对临床收集的187例青年(≤45岁)颈心综合征患者的临床资料进行分析。探讨青年颈心综合征临床误诊为冠心病的原因及避免误诊的诊疗策略。目的在于帮助临床医师对青年颈心综合征进行识别,注意如何与冠心病心绞痛相鉴别,对防止病情延误,尽早明确诊断积极治疗,排除冠心病,减少诊疗费用及避免冠脉造影的风险意义很大。     

慢性房颤导管消融策略的原则和个体化治疗

目前,慢性房颤导管消融的成功率及复发率均不尽人意。由于缺乏统一术式,慢性房颤消融采用的是肺静脉隔离、电图靶向消融及线性消融等多术式综合策略。在房颤消融策略上,既要坚持肺静脉电隔离原则,又要体现消融术式选择和实施的个体化,阶梯消融综合术式的推出就是这种思维方法的具体运用。     

英语阅读策略培训对非英语专业本科生的影响*

旨在探讨英语阅读策略培训对非英语专业本科生英语阅读策略使用情况以及英语成绩的影响。对非英语专业大学生进行了一学期的英语阅读策略培训,使用几次英语阅读测试和自编的英语阅读策略调查问卷对实验组和对照组进行前后测。研究结果发现:(1)英语阅读策略培训能有效提高学生英语阅读策略的使用频率,帮助他们取得更好的阅读成绩;(2)与高水平学习者相比,中、低水平学习者可从策略培训中获得更大的收益。