情绪加工中杏仁核的效价特异性

杏仁核是情绪信息加工的关键脑区。近年来心理学和神经科学领域发现了杏仁核情绪加工的效价特异性现象,并且整体存在左侧杏仁核对正性情绪、右侧杏仁核对负性情绪以及双侧杏仁核负性偏好的特异性趋势,且受到材料突出特征、个体差异、任务条件的调节。未来可进一步探索注意对杏仁核情绪效价特异性的调节作用,探究动态情绪刺激加工时杏仁核的活动特点,考察心理障碍患者加工负性情绪时的杏仁核激活模式,并确定杏仁核的效价特异性在思维、计划、决策等高级认知过程中的表现。     

Stress and memory: opposing effects of glucocorticoids on memory consolidation and memory retrieval

It is well established that glucocorticoid hormones, secreted by the adrenal cortex after a stressful event, influence cognitive performance. Some studies have found glucocorticoid-induced memory enhancement. However, many studies have reported impairing effects of glucocorticoids on memory function. This paper reviews recent findings from this laboratory on the acute effects of glucocorticoids in rats on specific memory phases, i.e., memory consolidation and memory retrieval. The evidence suggests that the consequences of glucocorticoid activation on cognition depend largely on the different memory phases investigated. Posttraining activation of glucocorticoid-sensitive pathways involving glucocorticoid receptors enhances memory consolidation in a pattern highly similar to that previously described for adrenal catecholamines. Also, similar to catecholamine effects on memory consolidation, glucocorticoid influences on memory consolidation depend on noradrenergic activation of the basolateral complex of the amygdala and interactions with other brain regions. By contrast, memory retrieval processes are usually impaired with high circulating levels of glucocorticoids or following infusions of glucocorticoid receptor agonists into the hippocampus. The hypothesis is proposed that these apparently dual effects of glucocorticoids on memory consolidation and memory retrieval might be related and that the basolateral complex of the amygdala is a key structure in a memory-modulatory system that regulates, in concert with other brain regions, stress and glucocorticoid effects on both memory consolidation and memory retrieval.     

Temperament and typology

This paper takes a cue from Harvard neuroscientists Jerome Kagan and Nancy Snidman's (2004) comment that Jung's work on typology has remarkable relevance to their research on neurobiological correlates of temperament and develops the links between the theorists separated by almost a century. The paper begins with a brief review of temperament traits in personality psychology. Kagan and Snidman's 11‐year longitudinal study is then analysed and correlated with Jung's psychological attitude types of introversion and extraversion, demonstrating that Jung's close empirical observations of human nature fit explicitly with objective measurements of neurobiological sensitivity thresholds and their expression in temperament. Emerging research on neurobiologically sensitive adults and children from Aron (1997, 2004, 2011) and differential susceptibility theory (DST) is presented as extrapolating the same links between temperament and physiological sensitivity found in Jung's introversion and Kagan and Snidman's high‐reactive type. The paper concludes with a consideration of the subjective psyche as a necessary aspect to understanding the self and human consciousness as whole.     

杏仁核对感觉刺激的情绪性加工:自动化过程和注意调控过程的整合

利用有限的认知资源应对多变的环境刺激,选择性注意和情绪加工一个重要的共同机制是优先化关键信息的加工。尽管情绪性刺激(特别是威胁刺激)能够影响注意资源的分配,但一些关键脑区(如杏仁核)的对情绪性刺激的加工是自动化过程还是受到注意调节一直是个有争议的问题。最新的结合高时间分辨率和高空间分辨率的神经生理记录研究表明,情绪加工的重要核团,杏仁核,对情绪性刺激的加工包含早期快速的不依赖于注意资源和认知加工负荷的自动化加工成分和晚期受到额-顶叶皮层自上而下的注意调控成分,这种功能整合证实杏仁核情绪性加工存在并行的皮层下和皮层通路。     

Automaticity and the Amygdala: Nonconscious Responses to Emotional Faces

The human face is an evolved adaptation for social communication. This implies that humans are genetically prepared to produce facial gestures that are automatically decoded by observers. Psychophysiological data demonstrate that humans respond automatically with their facial muscles, with autonomic responses, and with specific regional brain activation of the amygdala when exposed to emotionally expressive faces. Attention is preferentially and automatically oriented toward facial threat. Neuropsychological data, as well as a rapidly expanding brain-imaging literature, implicate the amygdala as a central structure for responding to negative emotional faces, and particularly to fearful ones. However, the amygdala may not be specialized for processing emotional faces, but may instead respond to faces because they provide important information for the defense appraisal that is its primary responsibility.     

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.     

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.     

对威胁刺激的注意偏向：注意定向加速还是注意解除困难？

对威胁刺激的注意偏向普遍存在。注意定向加速和注意解除困难在不同阶段对注意偏向产生影响。威胁刺激属性、呈现时间以及被试特征是重要的调节因素。以杏仁核为核心的杏仁核?前扣带回网络可能是注意定向加速的神经基础, 而以眶额叶为中心的前额叶皮层可能是注意解除的神经基础。未来还需要就注意定向加速与注意解除困难的关系、注意偏向的调节机制以及其神经基础做更深入的研究。     

早期应激对情绪调节的影响及其神经机制

在个体生命早期遭遇的长期或重大的应激经历会显著增加个体罹患抑郁、焦虑等心理疾患的风险, 而情绪调节能力的损伤是引发这些心理疾患的重要因素之一。以人类为对象的行为实验和调查研究表明, 早期应激不仅会影响日常生活中情绪调节策略的使用, 还会对情绪调节能力造成影响, 其影响方向可能与早期应激的严重程度有关。目前, 大部分研究表明严重的早期应激会损伤情绪调节能力, 但中度的早期应激也可能提高情绪调节能力。更为整合性的研究表明情绪调节能力中介了早期应激和各类疾患之间的关系。进一步, 我们从神经层面上阐述了早期应激对情绪调节相关脑区和神经环路的影响。未来研究应当注意控制无关变量, 进一步探究不同早期应激对于情绪调节的影响。