Disorders of emotional behaviour.
Gainotti G
Journal of neurology
After having stressed the distinction between general adaptive systems and specific functional systems, the author argues that emotions constitute a general adaptive system distinct from, but interacting with, the cognitive system, considered as the other (more evolved) adaptive system. The main characteristics of the emotional system are its componential nature and its hierarchical organization. These basic features of the emotional system, as well as the brain structures subserving the different components of emotions must, therefore, be taken into account in the neuropsychological study of emotional disorders. The main components of emotions considered in this educational review are: the evaluation of emotional situations; the emotional response with its expressive-motor and autonomic components and the inhibition of socially unacceptable spontaneous emotional responses. The main levels identified in the hierarchical structure of emotions are: a level of automatic, spontaneous functioning and a level of conceptual processing of emotional information and of controlled selection of the most appropriate response. The brain structures identified as critically involved in these different components and levels of emotions are: the amygdala, considered as the structure where the external stimuli are appraised in terms of their emotional significance; the insular cortex and the hypothalamus, crucially involved in the generation of the autonomic components of emotions; the ventral striatum, which subserves the execution of stereotyped emotional action patterns and the ventro-medial frontal cortex, playing a critical role in functions of control and inhibition of socially unacceptable emotional responses. The different emotional involvement of the right and left hemispheres in different aspects and levels of emotional processing is also shortly discussed and the quality of emotional disturbances resulting from injury to these brain structures is briefly considered.
Emotion-regulation choice.
Sheppes Gal,Scheibe Susanne,Suri Gaurav,Gross James J
Psychological science
Despite centuries of speculation about how to manage negative emotions, little is actually known about which emotion-regulation strategies people choose to use when confronted with negative situations of varying intensity. On the basis of a new process conception of emotion regulation, we hypothesized that in low-intensity negative situations, people would show a relative preference to choose to regulate emotions by engagement reappraisal, which allows emotional processing. However, we expected people in high-intensity negative situations to show a relative preference to choose to regulate emotions by disengagement distraction, which blocks emotional processing at an early stage before it gathers force. In three experiments, we created emotional contexts that varied in intensity, using either emotional pictures (Experiments 1 and 2) or unpredictable electric stimulation (Experiment 3). In response to these emotional contexts, participants chose between using either reappraisal or distraction as an emotion-regulation strategy. Results in all experiments supported our hypothesis. This pattern in the choice of emotion-regulation strategies has important implications for the understanding of healthy adaptation.
10.1177/0956797611418350
Dopamine transporter regulates the enhancement of novelty processing by a negative emotional context.
Garcia-Garcia Manuel,Clemente Immaculada,Domínguez-Borràs Judith,Escera Carles
Neuropsychologia
The dopaminergic (DA) system has been recently related the emotional modulation of cognitive processes. Moreover, patients with midbrain DA depletion, such as Parkinson's Disease (PD), have shown diminished reactivity during unpleasant events. Here, we examined the role of DA in the enhancement of novelty processing during negative emotion. Forty healthy volunteers were genotyped for the dopamine transporter (DAT) gene SLC6A3 or DAT1 and performed an auditory-visual distraction paradigm in negative and neutral emotional context conditions. 9R- individuals, associated to a lesser striatal DA display, failed to show increased distraction during negative emotion, but experienced an enhancement of the early phase of the novelty-P3 brain response, associated to the evaluation of novel events, in the negative relative to the neutral context. However, 9R+ individuals (associated to larger striatal DA display) showed larger distraction during negative emotion and larger amplitudes of the novelty-P3, irrespective of the condition. These results suggest a blunted reactivity to novelty during negative emotion in 9R- individuals due to a lesser DA display and stronger activation of the representation of novel events in the 9R+ group, due to a larger DA availability, thus reaching a ceiling effect in the neutral context condition with no further enhancement during negative emotion. The present results might help to understand the functional implications of dopamine in some neuropsychiatric disorders.
10.1016/j.neuropsychologia.2010.01.018
A distinct D1-MSN subpopulation down-regulates dopamine to promote negative emotional state.
Cell research
Dopamine (DA) level in the nucleus accumbens (NAc) is critical for reward and aversion encoding. DA released from the ventral mesencephalon (VM) DAergic neurons increases the excitability of VM-projecting D1-dopamine receptor-expressing medium spiny neurons (D1-MSNs) in the NAc to enhance DA release and augment rewards. However, how such a DA positive feedback loop is regulated to maintain DA homeostasis and reward-aversion balance remains elusive. Here we report that the ventral pallidum (VP) projection of NAc D1-MSNs (D1) is inhibited by rewarding stimuli and activated by aversive stimuli. In contrast to the VM projection of D1-MSN (D1), activation of D1 projection induces aversion, but not reward. D1 MSNs are distinct from the D1 MSNs, which exhibit conventional functions of D1-MSNs. Activation of D1 projection stimulates VM GABAergic transmission, inhibits VM DAergic neurons, and reduces DA release into the NAc. Thus, D1 and D1 MSNs cooperatively control NAc dopamine balance and reward-aversion states.
10.1038/s41422-021-00588-5
Allopregnanolone in mood disorders: Mechanism and therapeutic development.
Chen Shiyi,Gao Lijuan,Li Xiaoyu,Ye Yiping
Pharmacological research
The neuroactive steroid allopregnanolone (ALLO) is an endogenous positive allosteric modulator of GABA type A receptor (GABAR), and the down-regulation of its biosynthesis have been attributed to the development of mood disorders, such as depression, anxiety and post-traumatic stress disorder (PTSD). ALLO mediated depression/anxiety involves GABAergic mechanisms and appears to be related to brain-derived neurotrophic factor (BDNF), dopamine receptor, glutamate neurotransmission, and Ca channel. In the clinical, brexanolone, as a newly developed intravenous ALLO preparation, has been approved for the treatment of postpartum depression (PPD). In addition, traditional antidepressants such as selective serotonin reuptake inhibitor (SSRI) could reverse ALLO decline. Recently, the translocation protein (TSPO, 18 kDa), which involves in the speed-limiting step of ALLO synthesis, and ALLO derivatization have been identified as new directions for antidepressant therapy. This review provides an overview of ALLO researches in animal model and patients, discusses its role in the development and treatment of depression/anxiety, and directs its therapeutic potential in future.
10.1016/j.phrs.2021.105682
Study on the Progress of Neural Mechanism of Positive Emotions.
Yin Jie
Translational neuroscience
Positive emotions refer to emotions accompanied by pleasant feelings, such as happiness, interest, satisfaction, pride, and love, which are generated by individuals in response to internal and external stimuli and events. Positive emotions are conscious processes that involve a variety of components, such as a pleasant experience, facial/body expressions, evaluations, and especially behavioural plans and activation states. People's cognitive process is often accompanied by emotions, and the influence of positive emotions on cognitive activities has gradually become the focus of research in recent years. This study constructs a regulation model and an assessment model of positive emotions, and analyses the neural mechanisms of the effects of dopamine substances on human positive emotions.
10.1515/tnsci-2019-0016