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。     

The medial amygdala: Serotonergic inhibition of shock-lnduced aggression and pain sensitivity in rats

Two aspects of the amygdaloid complex (corticomedial and basolateral) were examined with reference to serotonergic inhibition of shock-induced aggression. Fighting was significantly depressed by serotonergic stimulation (5-HT, 10 μg bilateral) in the corticomedial amygdala while serotonergic blockade (methysergide, 5 μg bilateral) in this region increased levels of fighting. No consistent effects were obtained with serotonergic manipulation of the basolateral amygdala. Further investigation revealed that the state of serotonergic activity in medial amygdaloid sites was associated with concomitant alterations in the animals' sensitivity to footshock. Results are discussed in relation to a) a general inhibitory role of serotonin in behavioural mechanisms and b) a dopaminergic-serotonergic balance for behavioural arousal involving medial amygdaloid nuclei.     

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.     

Dopamine regulation of human speech and bird song: a critical review

To understand the neural basis of human speech control, extensive research has been done using a variety of methodologies in a range of experimental models. Nevertheless, several critical questions about learned vocal motor control still remain open. One of them is the mechanism(s) by which neurotransmitters, such as dopamine, modulate speech and song production. In this review, we bring together the two fields of investigations of dopamine action on voice control in humans and songbirds, who share similar behavioral and neural mechanisms for speech and song production. While human studies investigating the role of dopamine in speech control are limited to reports in neurological patients, research on dopaminergic modulation of bird song control has recently expanded our views on how this system might be organized. We discuss the parallels between bird song and human speech from the perspective of dopaminergic control as well as outline important differences between these species.     

Disentangling the neural mechanisms involved in Hinduism- and Buddhism-related meditations

The most diffuse forms of meditation derive from Hinduism and Buddhism spiritual traditions. Different cognitive processes are set in place to reach these meditation states. According to an historical-philological hypothesis (Wynne, 2009) the two forms of meditation could be disentangled. While mindfulness is the focus of Buddhist meditation reached by focusing sustained attention on the body, on breathing and on the content of the thoughts, reaching an ineffable state of nothigness accompanied by a loss of sense of self and duality (Samadhi) is the main focus of Hinduism-inspired meditation. It is possible that these different practices activate separate brain networks. We tested this hypothesis by conducting an activation likelihood estimation (ALE) meta-analysis of functional magnetic resonance imaging (fMRI) studies. The network related to Buddhism-inspired meditation (16 experiments, 263 subjects, and 96 activation foci) included activations in some frontal lobe structures associated with executive attention, possibly confirming the fundamental role of mindfulness shared by many Buddhist meditations. By contrast, the network related to Hinduism-inspired meditation (8 experiments, 54 activation foci and 66 subjects) triggered a left lateralized network of areas including the postcentral gyrus, the superior parietal lobe, the hippocampus and the right middle cingulate cortex. The dissociation between anterior and posterior networks support the notion that different meditation styles and traditions are characterized by different patterns of neural activation.     

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.     

The amygdalostriatal and corticostriatal effective connectivity in anticipation and evaluation of facial attractiveness

Decision-making consists of several stages of information processing, including an anticipation stage and an outcome evaluation stage. Previous studies showed that the ventral striatum (VS) is pivotal to both stages, bridging motivation and action, and it works in concert with the ventral medial prefrontal cortex (vmPFC) and the amygdala. However, evidence concerning how the VS works together with the vmPFC and the amygdala came mainly from neuropathology and animal studies; little is known about the dynamics of this network in the functioning human brain. Here we used fMRI combined with dynamic causal modeling (DCM) to investigate the information flow along amygdalostriatal and corticostriatal pathways in a facial attractiveness guessing task. Specifically, we asked participants to guess whether a blurred photo of female face was attractive and to wait for a few seconds (“anticipation stage”) until an unblurred photo of feedback face, which was either attractive or unattractive, was presented (“outcome evaluation stage”). At the anticipation stage, the bilateral amygdala and VS showed higher activation for the “attractive” than for the “unattractive” guess. At the outcome evaluation stage, the vmPFC and the bilateral VS were more activated by feedback faces whose attractiveness was congruent with the initial guess than by incongruent faces; however, this effect was only significant for attractive faces, not for unattractive ones. DCM showed that at the anticipation stage, the choice-related information entered the amygdalostriatal pathway through the amygdala and was projected to the VS. At the evaluation stage, the outcome-related information entered the corticostriatal pathway through the vmPFC. Bidirectional connectivities existed between the vmPFC and VS, with the VS-to-vmPFC connectivity weakened by unattractive faces. These findings advanced our understanding of the reward circuitry by demonstrating the pattern of information flow along the amygdalostriatal and corticostriatal pathways at different stages of decision-making.     

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.