The neural underpinnings of facial emotion recognition in ischemic stroke patients

Deficits in facial emotion recognition occur frequently after stroke, with adverse social and behavioural consequences. The aim of this study was to investigate the neural underpinnings of the recognition of emotional expressions, in particular of the distinct basic emotions (anger, disgust, fear, happiness, sadness and surprise). A group of 110 ischaemic stroke patients with lesions in (sub)cortical areas of the cerebrum was included. Emotion recognition was assessed with the Ekman 60 Faces Test of the FEEST. Patient data were compared to data of 162 matched healthy controls (HC’s). For the patients, whole brain voxel-based lesion–symptom mapping (VLSM) on 3-Tesla MRI images was performed. Results showed that patients performed significantly worse than HC’s on both overall recognition of emotions, and specifically of disgust, fear, sadness and surprise. VLSM showed significant lesion–symptom associations for FEEST total in the right fronto-temporal region. Additionally, VLSM for the distinct emotions showed, apart from overlapping brain regions (insula, putamen and Rolandic operculum), also regions related to specific emotions. These were: middle and superior temporal gyrus (anger); caudate nucleus (disgust); superior corona radiate white matter tract, superior longitudinal fasciculus and middle frontal gyrus (happiness) and inferior frontal gyrus (sadness). Our findings help in understanding how lesions in specific brain regions can selectively affect the recognition of the basic emotions.     

Individual differences in skilled adult readers reveal dissociable patterns of neural activity associated with component processes of reading

We used fMRI to examine patterns of brain activity associated with component processes of visual word recognition and their relationships to individual differences in reading skill. We manipulated both the judgments adults made on written stimuli and the characteristics of the stimuli. Phonological processing led to activation in left inferior frontal and temporal regions whereas semantic processing was associated with bilateral middle frontal activation. Individual differences in reading subskills were reflected in differences in the degree to which cortical regions were engaged during reading. Variation in sight word reading efficiency was associated with degree of activation in visual cortex. Increased phonological decoding skill was associated with greater activation in left temporo-parietal cortex. Greater reading comprehension ability was associated with decreased activation in anterior cingulate and temporal regions. Notably, associations between reading ability and neural activation indicate that brain/behavior relationships among skilled readers differ from patterns associated with dyslexia and reading development.     

基本情绪的神经基础：来自fMRI与机器视觉技术研究的证据

基本情绪理论(basic emotion theory)是情绪科学领域最具代表性的理论, 该理论认为人类情绪是由有限的几种基本情绪组成的, 如恐惧、愤怒、喜悦、悲伤等。基本情绪是为了完成基本生命任务(fundamental life task)进化而来的, 每一种基本情绪都有独特的神经结构和生理基础。尽管基本情绪理论被广泛接受, 但是对于基本情绪的种类却莫衷一是。近几十年来, 许多fMRI研究试图确定各种基本情绪的独特神经结构基础, 而且取得了许多重要发现, 比如厌恶和脑岛有关, 悲伤和前扣带回有关, 杏仁核是与恐惧有关的重要边缘结构等。但是, 最近有人进行了元分析研究, 发现许多基本情绪存在混淆的大脑区域, 因此对基本情绪的特定脑区理论提出质疑, 甚至否定基本情绪理论。通过对基本情绪及其神经基础的探讨, 以及对基本情绪理论的最新功能性磁共振成像研究进行梳理分析, 提出有关基本情绪理论的争论来源于基本情绪种类的确定, 因为许多所谓的不同基本情绪实际上是同一种基本情绪, 提出人类可能只有3种基本情绪。未来研究可以利用机器视觉技术进一步推动基本情绪脑影像研究。     

Dissociable neural systems for recognizing emotions

This study tested the hypothesis that the recognition of emotions would draw upon anatomically separable brain regions, depending on whether the stimuli were static or explicitly conveyed information regarding actions. We investigated the hypothesis in a rare subject with extensive bilateral brain lesions, patient B., by administering tasks that assessed recognition and naming of emotions from visual and verbal stimuli, some of which depicted actions and some of which did not. B. could not recognize any primary emotion other than happiness, when emotions were shown as static images or given as single verbal labels. By contrast, with the notable exception of disgust, he correctly recognized primary emotions from dynamic displays of facial expressions as well as from stories that described actions. Our findings are consistent with the idea that information about actions is processed in occipitoparietal and dorsal frontal cortices, all of which are intact in B.'s brain. Such information subsequently would be linked to knowledge about emotions that depends on structures mapping somatic states, many of which are also intact in B.'s brain. However, one of these somatosensory structures, the insula, is bilaterally damaged, perhaps accounting for B.'s uniformly impaired recognition of disgust (from both static and action stimuli). Other structures that are damaged in B.'s brain, including bilateral inferior and anterior temporal lobe and medial frontal cortices, appear to be critical for linking perception of static stimuli to recognition of emotions. Thus the retrieval of knowledge regarding emotions draws upon widely distributed and partly distinct sets of neural structures, depending on the attributes of the stimulus.     

Facial expressions and the ability to recognize emotions from the eyes or mouth: A comparison among old adults,young adults,and children

The aim of the present study was to contribute to the literature on the ability to recognize anger, happiness, fear, surprise, sadness, disgust, and neutral emotions from facial information (whole face, eye region, mouth region). More specifically, the aim was to investigate older adults' performance in emotions recognition using the same tool used in the previous studies on children and adults’ performance and verify if the pattern of emotions recognition show differences compared with the other two groups. Results showed that happiness is among the easiest emotions to recognize while the disgust is always among the most difficult emotions to recognize for older adults. The findings seem to indicate that is more easily recognizing emotions when pictures represent the whole face; compared with the specific region (eye and mouth regions), older participants seems to recognize more easily emotions when the mouth region is presented. In general, the results of the study did not detect a decay in the ability to recognize emotions from the face, eyes, or mouth. The performance of the old adults is statistically worse than the other two groups in only a few cases: in anger and disgust recognition from the whole face; in anger recognition from the eye region; and in disgust, fear, and neutral emotion recognition from mouth region.     

Emotional appraisal is influenced by cardiac afferent information

Influential models highlight the central integration of bodily arousal with emotion. Some emotions, notably disgust, are more closely coupled to visceral state than others. Cardiac baroreceptors, activated at systole within each cardiac cycle, provide short-term visceral feedback. Here we explored how phasic baroreceptor activation may alter the appraisal of brief emotional stimuli and consequent cardiovascular reactions. We used functional MRI (fMRI) to measure brain responses to emotional face stimuli presented before and during cardiac systole. We observed that the processing of emotional stimuli was altered by concurrent natural baroreceptor activation. Specifically, facial expressions of disgust were judged as more intense when presented at systole, and rebound heart rate increases were attenuated after expressions of disgust and happiness. Neural activity within prefrontal cortex correlated with emotionality ratings. Activity within periaqueductal gray matter reflected both emotional ratings and their interaction with cardiac timing. Activity within regions including prefrontal and visual cortices correlated with increases in heart rate evoked by the face stimuli, while orbitofrontal activity reflected both evoked heart rate change and its interaction with cardiac timing. Our findings demonstrate that momentary physiological fluctuations in cardiovascular afferent information (1) influence specific emotional judgments, mediated through regions including the periaqueductal gray matter, and (2) shape evoked autonomic responses through engagement of orbitofrontal cortex. Together these findings highlight the close coupling of visceral and emotional processes and identify neural regions mediating bodily state influences on affective judgment.     

Functional neuroanatomy of emotions: A meta-analysis

The application of functional neuroimaging to the study of human emotion has yielded valuable data; however, the conclusions that may be drawn from any one study are limited. We applied novel statistical techniques to the meta-analysis of 106 PET and fMRI studies of human emotion and tested predictions made by key neuroscientific models. The results demonstrated partial support for asymmetry accounts. Greater left-sided activity was observed for approach emotions, whereas neural activity associated with negative/withdrawal emotions was symmetrical. Support was also found for affect program emotion accounts. The activation distributions associated with fear, disgust, and anger differed significantly. These emotions were most consistently associated in activity in regions associated with selective processing deficits when damaged: the amygdala, the insula and globus pallidus, and the lateral orbitofrontal cortex, respectively. In contrast, the distributions for happiness and sadness did not differ. These findings are considered in the context of conceptualizations of the neural correlates of human emotion.     

Emotions: From neuropsychology to functional imaging

Recent developments in functional imaging techniques, such as Positron Emission Tomography (PET) and functional Magnetic Resonance Imaging (fMRI), allow us to characterize more precisely the functional neuroanatomy mediating emotional responding. This corpus of studies has led to the development of affective neuroscience. First, we present a summary of the studies aimed at understanding the underlying mechanisms of the emotional response, which were conducted prior to the use of the brain imaging techniques. Then, this paper reviews the studies investigating the neural substrates implicated in the processing of facial expressions and those implicated in the production of experimentally induced emotional responses. This review of the literature includes a meta‐analysis of eight studies using PET and one fMRI study reporting the neural correlates of experimentally induced emotions in healthy individuals. The methods and results of these studies are described through figures drawn from the reported Talairach's coordinates depicting the cerebral regions activated in relation to different experimental conditions. The implications of the results and the role of the cerebral structures that have been identified are discussed. As regards the studies on the neural bases of the processing of facial expressions of emotion, there are separable neural circuits that are involved in mediating responding to differing categories of facial expressions of emotion. Fearful expressions have relatively consistently been found to activate the amygdala, as, occasionally, have sad and happy expressions. The anterior insula and the putamen seem to be particularly involved in disgust expression recognition, whereas the facial expression of anger seems to be predominantly associated with anterior cingular and orbitofrontal cortex activity. Among the cerebral structures that have appeared to be activated by experimentally induced emotions, the anterior cingulate cortex seems to play a specific role in representing subjective emotional responses.     

Neural systems for recognition of emotional prosody: a 3-D lesion study

Which brain regions are associated with recognition of emotional prosody? Are these distinct from those for recognition of facial expression? These issues were investigated by mapping the overlaps of co-registered lesions from 66 brain-damaged participants as a function of their performance in rating basic emotions. It was found that recognizing emotions from prosody draws on the right frontoparietal operculum, the bilateral frontal pole, and the left frontal operculum. Recognizing emotions from prosody and facial expressions draws on the right frontoparietal cortex, which may be important in reconstructing aspects of the emotion signaled by the stimulus. Furthermore, there were regions in the left and right temporal lobes that contributed disproportionately to recognition of emotion from faces or prosody, respectively.     

Smiles when lying

Subtle differences among forms of smiling distinguished when subjects were truthful and when they lied about experiencing pleasant feelings. Expressions that included muscular activity around the eyes in addition to the smiling lips occurred more often when people were actually enjoying themselves as compared with when enjoyment was feigned to conceal negative emotions. Smiles that included traces of muscular actions associated with disgust, fear, contempt, or sadness occurred more often when subjects were trying to mask negative emotions with a happy mask. When these differences among types of smiling were ignored and smiling was treated as a unitary phenomenon, there was no difference between truthful and deceptive behavior.     

Facial Emotion Processing in Borderline Personality Disorder: A Systematic Review and Meta-Analysis

A body of work has developed over the last 20 years that explores facial emotion perception in Borderline Personality Disorder (BPD). We identified 25 behavioural and functional imaging studies that tested facial emotion processing differences between patients with BPD and healthy controls through a database literature search. Despite methodological differences there is consistent evidence supporting a negative response bias to neutral and ambiguous facial expressions in patients. Findings for negative emotions are mixed with evidence from individual studies of an enhanced sensitivity to fearful expressions and impaired facial emotion recognition of disgust, while meta-analysis revealed no significant recognition impairments between BPD and healthy controls for any negative emotion. Mentalizing studies indicate that BPD patients are accurate at attributing mental states to complex social stimuli. Functional neuroimaging data suggest that the underlying neural substrate involves hyperactivation in the amygdala to affective facial stimuli, and altered activation in the anterior cingulate, inferior frontal gyrus and the superior temporal sulcus particularly during social emotion processing tasks. Future studies must address methodological inconsistencies, particularly variations in patients’ key clinical characteristics and in the testing paradigms deployed.     

Production of spontaneous and posed facial expressions in patients with Huntington's disease: Impaired communication of disgust

Several studies have reported impairment in the recognition of facial expressions of disgust in patients with Huntington's disease (HD) and preclinical carriers of the HD gene. The aim of this study was to establish whether impairment for disgust in HD patients extended to include the ability to express the emotion on their own faces. Eleven patients with HD, and 11 age and education matched healthy controls participated in three tasks concerned with the expression of emotions. One task assessed the spontaneous production of disgust-like facial expressions during the smelling of offensive odorants. A second assessed the production of posed facial expressions during deliberate attempts to communicate emotion. The third task evaluated HD patients’ ability to imitate the specific facial configurations associated with each emotion. Foul odours induced fewer disgust-like facial reactions in HD patients than in controls, and patients’ posed facial expressions of disgust were less accurate than the posed disgust expressions of controls. The effect was selective to disgust; patients had no difficulty posing expressions of other emotions. These impairments were not explained by compromised muscle control: HD patients had no difficulty imitating the facial movements required to display disgust. Viewed together with evidence of difficulty in other aspects of disgust in HD, the findings suggest that a common substrate might participate in both the processing and the expression of this emotion.     

Sex differences in attention to disgust facial expressions

Research demonstrates that women experience disgust more readily and with more intensity than men. The experience of disgust is associated with increased attention to disgust-related stimuli, but no prior study has examined sex differences in attention to disgust facial expressions. We hypothesised that women, compared to men, would demonstrate increased attention to disgust facial expressions. Participants (n?=?172) completed an eye tracking task to measure visual attention to emotional facial expressions. Results indicated that women spent more time attending to disgust facial expressions compared to men. Unexpectedly, we found that men spent significantly more time attending to neutral faces compared to women. The findings indicate that women’s increased experience of emotional disgust also extends to attention to disgust facial stimuli. These findings may help to explain sex differences in the experience of disgust and in diagnoses of anxiety disorders in which disgust plays an important role.     

厌恶与恐惧情绪习得的性别差异研究:一项ERP研究

采用事件相关电位技术（ERPs）,用条件性习得范式探讨厌恶与恐惧情绪习得的性别差异。行为结果表明,在成功习得厌恶、恐惧和中性情绪之后,男女性在唤醒度维度上,性别差异显著;脑电结果表明,在早期N1和P2成分,厌恶情绪与恐惧情绪的习得无显著性别差异;但男女不同性别在N2成分上差异显著,主要表现为女性在厌恶、恐惧、中性这三类CS的N2成分均差异显著,但男性仅厌恶与中性情绪的CS差异显著。结果表明在负性情绪的习得中,女性比男性更敏感。     

认知重评和表达抑制情绪调节策略的脑网络分析：来自EEG和ERP的证据

本文旨在对认知重评和表达抑制两种常用情绪调节策略的自发脑网络特征及认知神经活动进行深入探讨。研究采集36名在校大学生的静息态和任务态脑电数据, 经过源定位和图论分析发现节点效率与两种情绪调节显著相关的脑区, 以及脑区之间的功能连接。研究结果表明, 在使用认知重评进行情绪调节时会激活前额叶皮质、前扣带回、顶叶、海马旁回和枕叶等多个脑区, 在使用表达抑制进行情绪调节时会激活前额叶皮质、顶叶、海马旁回、枕叶、颞叶和脑岛等多个脑区。因此, 这些脑区的节点效率或功能连接强度可能成为评估个体使用认知重评和表达抑制调节情绪效果的指标。     

Individual differences in anterior brain asymmetry and fundamental dimensions of emotion.

This research assessed whether individual differences in anterior brain asymmetry are linked to differences in basic dimensions of emotion. In each of 2 experimental sessions, separated by 3 weeks, resting electroencephalogram (EEG) activity was recorded from female adults during 8 60-s baselines. Mean alpha power asymmetry across both sessions was extracted in mid-frontal and anterior temporal sites. Across both regions, groups demonstrating stable and extreme relative left anterior activation reported increased generalized positive affect (PA) and decreased generalized negative affect (NA) compared with groups demonstrating stable and extreme relative right anterior activation. Additional correlational analyses revealed robust relations between anterior asymmetry and PA and NA, particularly among subjects who demonstrated stable patterns of EEG activation over time. Anterior asymmetry was unrelated to individual differences in generalized reactivity.     

The influence of maternal anxiety and depression symptoms on fNIRS brain responses to emotional faces in 5- and 7-month-old infants

Greater relative right (versus left) frontal cortical activation to emotional faces as measured with alpha power in the electroencephalogram (EEG), has been considered a promising neural marker of increased vulnerability to psychopathology and emotional disorders. We set out to explore multichannel fNIRS as a tool to investigate infants’ frontal asymmetry responses (hypothesizing greater right versus left frontal cortex activation) to emotional faces as influenced by maternal anxiety and depression symptoms during the postnatal period. We also explored activation differences in fronto-temporal regions associated with facial emotion processing. Ninety-one typically developing 5- and 7-month-old infants were shown photographs of women portraying happy, fearful and angry expressions. Hemodynamic brain responses were analyzed over two frontopolar and seven bilateral cortical regions subdivided into frontal, temporal and parietal areas, defined by age-appropriate MRI templates. Infants of mothers reporting higher negative affect had greater oxyhemoglobin (oxyHb) activation across all emotions over the left inferior frontal gyrus, a region implicated in emotional communication. Follow-up analyses indicated that associations were driven by maternal depression, but not anxiety symptoms. Overall, we found no support for greater right versus left frontal cortex activation in association with maternal negative affect. Findings point to the potential utility of fNIRS as a method for identifying altered neural substrates associated with exposure to maternal depression in infancy.     

Bodily expression of emotion

The question whether body movements and body postures are indicative of specific emotions is a matter of debate. While some studies have found evidence for specific body movements accompanying specific emotions, others indicate that movement behavior (aside from facial expression) may be only indicative of the quantity (intensity) of emotion, but not of its quality. The study reported here is an attempt to demonstrate that body movements and postures to some degree are specific for certain emotions. A sample of 224 video takes, in which actors and actresses portrayed the emotions of elated joy, happiness, sadness, despair, fear, terror, cold anger, hot anger, disgust, contempt, shame, guilt, pride, and boredom via a scenario approach, was analyzed using coding schemata for the analysis of body movements and postures. Results indicate that some emotion-specific movement and posture characteristics seem to exist, but that for body movements differences between emotions can be partly explained by the dimension of activation. While encoder (actor) differences are rather pronounced with respect to specific movement and posture habits, these differences are largely independent from the emotion-specific differences found. The results are discussed with respect to emotion-specific discrete expression models in contrast to dimensional models of emotion encoding. Copyright © 1998 John Wiley & Sons, Ltd.