Diverse sensory cues for individual recognition

To be social, the ability to recognize and discriminate conspecific individuals is indispensable in social animals, including primates, rodents, birds, fish, and social insects which live in societies or groups. Recent studies using molecular biology, genetics, in vivo and in vitro physiology, and behavioral neuroscientific approaches have provided detailed insights into how animals process and recognize the information of individuals. Here, we review the most distinct sensory modalities for individual recognition in animals, namely, olfaction and vision. In the case of rodents, two polymorphic gene complexes have been identified in their urine as the key and essential pheromonal components for individual recognition: the major histocompatibility complex (MHC) and the major urinary protein (MUP). Animals flexibly utilize MHC and/or MUP, which are detected by the main olfactory epithelium (MOE) and/or the vomeronasal organ (VNO) for various types of social recognition, such as strain recognition, kin recognition, and individual recognition. In contrast, primates, including humans, primarily use facial appearance to identify others. Face recognition in humans and other animals is naturally unique from genetic, cognitive, developmental, and functional points of view. Importantly note that nurture effects during growth phase such as social experience and environment can also shape and tune this special cognitive ability, in order to distinguish subtle differences between individuals. In this review, we address such unique nature and nurture mechanisms for individual recognition.     

Observational fear behavior in rodents as a model for empathy

Empathy enables social mammals to recognize and share emotion with others and is well‐documented in non‐human primates. During the past few years, systematic observations have showed that a primal form of empathy also exists in rodents, indicating that empathy has an evolutionary continuity. Now, using rodents exhibiting emotional empathy, the molecular and cellular study of empathy in animals has begun in earnest. In this article, we will review recent reports that indicate that rodents can share states of fear with others, and will try to highlight new understandings of the neural circuitry, biochemistry and genetics of empathic fear. We hope that the use of rodent models will enhance understanding of the mechanisms of human empathy and provide insights into how to treat social deficits in neuropsychiatric disorders characterized by empathy impairment.     

Factors affecting the Human Attribution of Emotions toward Animals

ABSTRACT

Attribution of emotions to animals can affect human–animal interactions and dictate animal welfare laws. However, little is known about the factors that influence these attributions. We investigated the effect of belief in animal mind, pet ownership, emotional intelligence, eating orientation, and gender on the attribution of different emotions to a variety of species, from different taxonomic classes, considered as Pet, Use (e.g., used for food, experimentation), or Pest animals. Three hundred and forty-seven participants, aged between 16 and 65 years, completed a questionnaire that measured their belief in the capacity for animals to experience seven primary and secondary emotions. The results showed that attribution of emotions to animals is inconsistent. The ambiguity appears to hinge, in part, upon an animal's functional category and their perceived place in the commonly supposed, though inaccurate, linear hierarchy of species. Nonetheless, the wide range of emotions that were attributed to all species highlights the complex and potentially disorganized thoughts that humans have concerning animals. Belief in animal mind was found to be the strongest and only predictor of emotion attribution to animals in general, but is probably because both are part of the same underlying construct. Ownership of some species—rabbits, horses, rodents and birds—mediated the emotions attributed to that particular species. We conclude that ambiguous attitudes influence the standards of welfare for animals used by humans and that the dichotomous attitudes permit exploitation and welfare violations against animals. Greater understanding of emotion attribution has the potential to improve humane education methods, and suggestions for future research are made.     

Contributions of the amygdala to emotion processing: from animal models to human behavior

Research on the neural systems underlying emotion in animal models over the past two decades has implicated the amygdala in fear and other emotional processes. This work stimulated interest in pursuing the brain mechanisms of emotion in humans. Here, we review research on the role of the amygdala in emotional processes in both animal models and humans. The review is not exhaustive, but it highlights five major research topics that illustrate parallel roles for the amygdala in humans and other animals, including implicit emotional learning and memory, emotional modulation of memory, emotional influences on attention and perception, emotion and social behavior, and emotion inhibition and regulation.     

Congenital facial palsy and emotion processing: The case of Moebius syndrome

According to the Darwinian perspective, facial expressions of emotions evolved to quickly communicate emotional states and would serve adaptive functions that promote social interactions. Embodied cognition theories suggest that we understand others' emotions by reproducing the perceived expression in our own facial musculature (facial mimicry) and the mere observation of a facial expression can evoke the corresponding emotion in the perceivers. Consequently, the inability to form facial expressions would affect the experience of emotional understanding. In this review, we aimed at providing account on the link between the lack of emotion production and the mechanisms of emotion processing. We address this issue by taking into account Moebius syndrome, a rare neurological disorder that primarily affects the muscles controlling facial expressions. Individuals with Moebius syndrome are born with facial paralysis and inability to form facial expressions. This makes them the ideal population to study whether facial mimicry is necessary for emotion understanding. Here, we discuss behavioral ambiguous/mixed results on emotion recognition deficits in Moebius syndrome suggesting the need to investigate further aspects of emotional processing such as the physiological responses associated with the emotional experience during developmental age.     

On the relationship of emotional abilities and prosocial behavior

The ability to perceive and infer the meaning of facial expressions has been considered a critical component of emotional intelligence being essential for successful social functioning: Longitudinal findings suggest that the ability to recognize emotion cues is related to positive social interactions. Moreover, pronounced recognition abilities for at least some emotions facilitate prosocial behavior in everyday situations. Integrating paradigms from behavioral economics and psychometrics, we used an interdisciplinary approach to study the relationship between prosociality as trait cooperativeness and the ability to recognize emotions in others. We measured emotion recognition accuracy (ERA) using a multivariate test battery. We captured prosocial behavior in standard socio-economic games, along with spontaneous emotion expressions. Structural equation modeling revealed no significant relationship between overall ERA and prosocial behavior. However, modeling emotion-specific factors suggested that more prosocial individuals are better in recognizing fear and tend to express more spontaneous emotions during the prisoner's dilemma. In all, cooperative individuals seem to be more sensitive to the distress of others and more expressive, possibly fostering reciprocal interactions with like-minded others.     

Exploring the behavioral and cognitive phenotype of KBG syndrome

KBG syndrome is a neurodevelopmental disorder, caused by dominant mutations in ANKRD11, that is characterized by developmental delay/intellectual disability, mild craniofacial dysmorphisms, and short stature. Behavior and cognition have hardly been studied, but anecdotal evidence suggests higher frequencies of ADHD‐symptoms and social‐emotional impairments. In this study, the behavioral and cognitive profile of KBG syndrome will be investigated in order to examine if and how cognitive deficits contribute to behavioral difficulties. A total of 18 patients with KBG syndrome and a control group consisting of 17 patients with other genetic disorders with comparable intelligence levels, completed neuropsychological assessment. Age‐appropriate tasks were selected, covering overall intelligence, attention, memory, executive functioning, social cognition and visuoconstruction. Results were compared using Cohen's d effect sizes. As to behavior, fewer difficulties in social functioning and slightly more attentional problems, hyperactivity, oppositional defiant behavior and conduct problems were found in the KBG syndrome group. Regarding cognitive functioning, inspection of the observed differences shows that patients with KBG syndrome showed lower scores on sustained attention, cognitive flexibility, and visuoconstruction. In contrast, the KBG syndrome group demonstrated higher scores on visual memory, social cognition and emotion recognition. The cognitive profile of KBG syndrome in this sample indicates problems in attention and executive functioning that may underlie the behavior profile which primarily comprises impulsive behavior. Contrary to expectations based on previous (case) reports, no deficits were found in social cognitive functioning. These findings are important for counseling purposes, for tailored education planning, and for the development of personalized intervention.     

Ultrasonic vocalizations of adult male Foxp2‐mutant mice: behavioral contexts of arousal and emotion

Adult mouse ultrasonic vocalizations (USVs) occur in multiple behavioral and stimulus contexts associated with various levels of arousal, emotion and social interaction. Here, in three experiments of increasing stimulus intensity (water; female urine; male interacting with adult female), we tested the hypothesis that USVs of adult males express the strength of arousal and emotion via different USV parameters (18 parameters analyzed). Furthermore, we analyzed two mouse lines with heterozygous Foxp2 mutations (R552H missense, S321X nonsense), known to produce severe speech and language disorders in humans. These experiments allowed us to test whether intact Foxp2 function is necessary for developing full adult USV repertoires, and whether mutations of this gene influence instinctive vocal expressions based on arousal and emotion. The results suggest that USV calling rate characterizes the arousal level, while sound pressure and spectrotemporal call complexity (overtones/harmonics, type of frequency jumps) may provide indices of levels of positive emotion. The presence of Foxp2 mutations did not qualitatively affect the USVs; all USV types that were found in wild‐type animals also occurred in heterozygous mutants. However, mice with Foxp2 mutations displayed quantitative differences in USVs as compared to wild‐types, and these changes were context dependent. Compared to wild‐type animals, heterozygous mutants emitted mainly longer and louder USVs at higher minimum frequencies with a higher occurrence rate of overtones/harmonics and complex frequency jump types. We discuss possible hypotheses about Foxp2 influence on emotional vocal expressions, which can be investigated in future experiments using selective knockdown of Foxp2 in specific brain circuits.     

无意识接受策略在挫折情景下的情绪调节效应:行为与生理证据

由于无意识调节过程具有节省认知资源的特征,本研究假设无意识接受策略相比有意识接受策略能更加有效地调控负性事件的情绪影响.实验以挫折任务诱发负面情绪同时记录被试的主观情绪体验与情绪相关的生理变化(心率).被试被随机分为控制组、有意识接受组和无意识接受组.结果显示,无意识接受组和有意识接受组在情绪体验上存在显著差异:在挫折诱发阶段有意识接受组比无意识接受组出现了更多正性情绪指标的下降.此外,相对于控制组,挫折情景下有意识接受和无意识接受都显著降低了被试情绪相关的心率活动水平;但两者的调节水平无显著差异.并且,心率活动水平可预测主观情绪体验强度:控制组的心率变化值与负性情绪变化值存在正相关关系,与正性情绪指标变化值存在负相关趋势.因此,在挫折情景下,无意识接受策略不仅能有效降低情绪相关的生理活动水平,且相比有意识接受策略对主观情绪体验具有更好的调节效果.这提示,无意识接受策略对于现实生活中的情绪调节具有重要启示意义.     

Dreaming and offline memory processing

The activities of the mind and brain never cease. Although many of our waking hours are spent processing sensory input and executing behavioral responses, moments of unoccupied rest free us to wander through thoughts of the past and future, create daydreams, and imagine fictitious scenarios. During sleep, when attention to sensory input is at a minimum, the mind continues to process information, using memory fragments to create the images, thoughts, and narratives that we commonly call 'dreaming'. Far from being a random or meaningless distraction, spontaneous cognition during states of sleep and resting wakefulness appears to serve important functions related to processing past memories and planning for the future. From single-cell recordings in rodents to behavioral studies in humans, recent studies in the neurosciences suggest a new conception of dreaming as part of a continuum of adaptive cognitive processing occurring across the full range of mind/brain states.     

Joyful by nature: approaches to investigate the evolution and function of joy in non-human animals

The nature and evolution of positive emotion is a major question remaining unanswered in science and philosophy. The study of feelings and emotions in humans and animals is dominated by discussion of affective states that have negative valence. Given the clinical and social significance of negative affect, such as depression, it is unsurprising that these emotions have received more attention from scientists. Compared to negative emotions, such as fear that leads to fleeing or avoidance, positive emotions are less likely to result in specific, identifiable, behaviours being expressed by an animal. This makes it particularly challenging to quantify and study positive affect. However, bursts of intense positive emotion (joy) are more likely to be accompanied by externally visible markers, like vocalisations or movement patterns, which make it more amenable to scientific study and more resilient to concerns about anthropomorphism. We define joy as intense, brief, and event-driven (i.e. a response to something), which permits investigation into how animals react to a variety of situations that would provoke joy in humans. This means that behavioural correlates of joy are measurable, either through newly discovered ‘laughter’ vocalisations, increases in play behaviour, or reactions to cognitive bias tests that can be used across species. There are a range of potential situations that cause joy in humans that have not been studied in other animals, such as whether animals feel joy on sunny days, when they accomplish a difficult feat, or when they are reunited with a familiar companion after a prolonged absence. Observations of species-specific calls and play behaviour can be combined with biometric markers and reactions to ambiguous stimuli in order to enable comparisons of affect between phylogenetically distant taxonomic groups. Identifying positive affect is also important for animal welfare because knowledge of positive emotional states would allow us to monitor animal well-being better. Additionally, measuring if phylogenetically and ecologically distant animals play more, laugh more, or act more optimistically after certain kinds of experiences will also provide insight into the mechanisms underlying the evolution of joy and other positive emotions, and potentially even into the evolution of consciousness.     

Long-Term Social Isolation Reduces Expression of the BDNF Precursor and Prolyl Endopeptidase in the Rat Brain

Biochemistry (Moscow) - Early-life stress is a risk factor for the development of behavioral and cognitive disorders in humans and animals. Such stressful situations include social isolation in...     

Bilateral amygdala damage linked to impaired ability to predict others' fear but preserved moral judgements about causing others fear

The amygdala is a subcortical structure implicated in both the expression of conditioned fear and social fear recognition. Social fear recognition deficits following amygdala lesions are often interpreted as reflecting perceptual deficits, or the amygdala''s role in coordinating responses to threats. But these explanations fail to capture why amygdala lesions impair both physiological and behavioural responses to multimodal fear cues and the ability to identify them. We hypothesized that social fear recognition deficits following amygdala damage reflect impaired conceptual understanding of fear. Supporting this prediction, we found specific impairments in the ability to predict others'' fear (but not other emotions) from written scenarios following bilateral amygdala lesions. This finding is consistent with the suggestion that social fear recognition, much like social recognition of states like pain, relies on shared internal representations. Preserved judgements about the permissibility of causing others fear confirms suggestions that social emotion recognition and morality are dissociable.     

Emotion recognition accuracy in healthy young females is associated with cycle phase

Several studies reported a significant influence of ovarian hormone status on cognition and person perception. In particular, it has been stated that female mating preferences are shifted during the menstrual cycle. It remains, however, unclear if facial emotion recognition, a prerequisite for successful social interaction, is also influenced by estradiol and progesterone levels. Hence, we investigated 32 healthy right-handed females, 15 during their follicular phase and 17 during their luteal phase and compared their recognition accuracy. Hormone levels were correlated with several neuropsychological parameters. Subjects were matched for age and education and did not differ in any neuropsychological function. Analysis of emotion recognition performance (ANOVA) revealed a significant effect of phase, showing higher accuracy in the follicular group. Furthermore, a significant negative correlation between progesterone level and emotion recognition performance emerged, indicating higher accuracy with lower progesterone levels, hence supporting the group differences. Our results indicate a significant association of menstrual cycle phase and thus ovarian hormone concentration on facial emotion recognition, with progesterone exerting a special influence on this social-emotional ability.     

Facial and Prosodic Emotion Recognition Deficits Associate with Specific Clusters of Psychotic Symptoms in Schizophrenia

Background

Patients with schizophrenia perform significantly worse on emotion recognition tasks than healthy participants across several sensory modalities. Emotion recognition abilities are correlated with the severity of clinical symptoms, particularly negative symptoms. However, the relationships between specific deficits of emotion recognition across sensory modalities and the presentation of psychotic symptoms remain unclear. The current study aims to explore how emotion recognition ability across modalities and neurocognitive function correlate with clusters of psychotic symptoms in patients with schizophrenia.

Methods

111 participants who met the DSM-IV diagnostic criteria for schizophrenia and 70 healthy participants performed on a dual-modality emotion recognition task, the Diagnostic Analysis of Nonverbal Accuracy 2-Taiwan version (DANVA-2-TW), and selected subscales of WAIS-III. Of all, 92 patients received neurocognitive evaluations, including CPT and WCST. These patients also received the PANSS for clinical evaluation of symptomatology.

Results

The emotion recognition ability of patients with schizophrenia was significantly worse than healthy participants in both facial and vocal modalities, particularly fearful emotion. An inverse correlation was noted between PANSS total score and recognition accuracy for happy emotion. The difficulty of happy emotion recognition and earlier age of onset, together with the perseveration error in WCST predicted total PANSS score. Furthermore, accuracy of happy emotion and the age of onset were the only two significant predictors of delusion/hallucination. All the associations with happy emotion recognition primarily concerned happy prosody.

Discussion

Deficits in emotional processing in specific categories, i.e. in happy emotion, together with deficit in executive function, may reflect dysfunction of brain systems underlying severity of psychotic symptoms, in particular the positive dimension.     

甲基苯丙胺成瘾者情绪加工障碍的机制及其临床干预方法的整合研究进展

近年来,在中国以甲基苯丙胺为代表的合成毒品使用人数已经超过海洛因等传统毒品,而且滥用问题日益严重.情绪问题是诱发甲基苯丙胺成瘾者复吸的重要因素.慢性使用甲基苯丙胺导致前额叶-边缘单胺类神经递质系统及相应神经环路结构和功能损害,是成瘾者出现情绪加工障碍的原因.本文从情绪体验、情绪识别与表达和线索诱发的情绪反应性三个方面总结甲基苯丙胺成瘾者情绪加工障碍的表现形式,及相应神经递质系统神经环路基础.指出易激惹和愤怒攻击行为是甲基苯丙胺成瘾过程需要重点关注的情绪问题,并进一步总结了甲基苯丙胺成瘾者情绪障碍的临床治疗和干预的潜在方法,包括药物手段、神经调控技术、认知与行为治疗等,特别是信息科学和脑科学的新技术,如虚拟现实整合多感觉通道的情绪信息,并结合神经调控技术可为甲基苯丙胺成瘾者情绪加工障碍的临床干预提供新的视角.     

Dealing with Feelings: Characterization of Trait Alexithymia on Emotion Regulation Strategies and Cognitive-Emotional Processing

Background

Alexithymia, or “no words for feelings”, is a personality trait which is associated with difficulties in emotion recognition and regulation. It is unknown whether this deficit is due primarily to regulation, perception, or mentalizing of emotions. In order to shed light on the core deficit, we tested our subjects on a wide range of emotional tasks. We expected the high alexithymics to underperform on all tasks.

Method

Two groups of healthy individuals, high and low scoring on the cognitive component of the Bermond-Vorst Alexithymia Questionnaire, completed questionnaires of emotion regulation and performed several emotion processing tasks including a micro expression recognition task, recognition of emotional prosody and semantics in spoken sentences, an emotional and identity learning task and a conflicting beliefs and emotions task (emotional mentalizing).

Results

The two groups differed on the Emotion Regulation Questionnaire, Berkeley Expressivity Questionnaire and Empathy Quotient. Specifically, the Emotion Regulation Quotient showed that alexithymic individuals used more suppressive and less reappraisal strategies. On the behavioral tasks, as expected, alexithymics performed worse on recognition of micro expressions and emotional mentalizing. Surprisingly, groups did not differ on tasks of emotional semantics and prosody and associative emotional-learning.

Conclusion

Individuals scoring high on the cognitive component of alexithymia are more prone to suppressive emotion regulation strategies rather than reappraisal strategies. Regarding emotional information processing, alexithymia is associated with reduced performance on measures of early processing as well as higher order mentalizing. However, difficulties in the processing of emotional language were not a core deficit in our alexithymic group.     

genetic overexpression of NR2B subunit enhances social recognition memory for different strains and species

The ability to learn and remember conspecifics is essential for the establishment and maintenance of social groups. Many animals, including humans, primates and rodents, depend on stable social relationships for survival. Social learning and social recognition have become emerging areas of interest for neuroscientists but are still not well understood. It has been established that several hormones play a role in the modulation of social recognition including estrogen, oxytocin and arginine vasopression. Relatively few studies have investigated how social recognition might be improved or enhanced. In this study, we investigate the role of the NMDA receptor in social recognition memory, specifically the consequences of altering the ratio of the NR2B:NR2A subunits in the forebrain regions in social behavior. We produced transgenic mice in which the NR2B subunit of the NMDA receptor was overexpressed postnatally in the excitatory neurons of the forebrain areas including the cortex, amygdala and hippocampus. We investigated the ability of both our transgenic animals and their wild-type littermate to learn and remember juvenile conspecifics using both 1-hr and 24-hr memory tests. Our experiments show that the wild-type animals and NR2B transgenic mice preformed similarly in the 1-hr test. However, transgenic mice showed better performances in 24-hr tests of recognizing animals of a different strain or animals of a different species. We conclude that NR2B overexpression in the forebrain enhances social recognition memory for different strains and animal species.     

An integrative and functional framework for the study of animal emotion and mood

A better understanding of animal emotion is an important goal in disciplines ranging from neuroscience to animal welfare science. The conscious experience of emotion cannot be assessed directly, but neural, behavioural and physiological indicators of emotion can be measured. Researchers have used these measures to characterize how animals respond to situations assumed to induce discrete emotional states (e.g. fear). While advancing our understanding of specific emotions, this discrete emotion approach lacks an overarching framework that can incorporate and integrate the wide range of possible emotional states. Dimensional approaches that conceptualize emotions in terms of universal core affective characteristics (e.g. valence (positivity versus negativity) and arousal) can provide such a framework. Here, we bring together discrete and dimensional approaches to: (i) offer a structure for integrating different discrete emotions that provides a functional perspective on the adaptive value of emotional states, (ii) suggest how long-term mood states arise from short-term discrete emotions, how they also influence these discrete emotions through a bi-directional relationship and how they may function to guide decision-making, and (iii) generate novel hypothesis-driven measures of animal emotion and mood.