Facial feedback hypotheses: Evidence, implications, and directions

Sensorimotor regulation of facial expression - An untouched frontier

Facial expression is a critical form of nonverbal social communication which promotes emotional exchange and affiliation among humans. Facial expressions are generated via precise contraction of the facial muscles, guided by sensory feedback. While the neural pathways underlying facial motor control are well characterized in humans and primates, it remains unknown how tactile and proprioceptive information reaches these pathways to guide facial muscle contraction. Thus, despite the importance of facial expressions for social functioning, little is known about how they are generated as a unique sensorimotor behavior. In this review, we highlight current knowledge about sensory feedback from the face and how it is distinct from other body regions. We describe connectivity between the facial sensory and motor brain systems, and call attention to the other brain systems which influence facial expression behavior, including vision, gustation, emotion, and interoception. Finally, we petition for more research on the sensory basis of facial expressions, asserting that incomplete understanding of sensorimotor mechanisms is a barrier to addressing atypical facial expressivity in clinical populations.

Inter-subject correlation of audience facial expressions predicts audience engagement during theatrical performances

During performances, audiences experience various emotional states, and these are reflected in their ongoing facial expressions. We investigated if audience engagement could be determined by measuring the inter-subject correlation (ISC) of non-invasively recorded audience facial expressions. We filmed the faces of multiple audience members at theatrical performances and determined the intensity of their different facial expressions throughout the performances. Neutral, happy, anger, and disgust expression ISCs accounted for up to 24% of the performance dramaturge's predictions of audience engagement. Expression synchrony was greater between individuals in close proximity, suggesting effects of emotional contagion or cognitive similarities between neighboring individuals, whereas expression synchrony was greatest between individuals who were younger, female, and with greater levels of empathy, showing that individual characteristics impact shared audience experiences. Together, our results show that facial expression synchronization could be used as a real-time non-invasive indicator of engagement in audiences larger than achieved using previous approaches.

Application of facial neuromuscular electrical stimulation (fNMES) in psychophysiological research: Practical recommendations based on a systematic review of the literature

Facial neuromuscular electrical stimulation (fNMES), which allows for the non-invasive and physiologically sound activation of facial muscles, has great potential for investigating fundamental questions in psychology and neuroscience, such as the role of proprioceptive facial feedback in emotion induction and emotion recognition, and may serve for clinical applications, such as alleviating symptoms of depression. However, despite illustrious origins in the 19th-century work of Duchenne de Boulogne, the practical application of fNMES remains largely unknown to today's researchers in psychology. In addition, published studies vary dramatically in the stimulation parameters used, such as stimulation frequency, amplitude, duration, and electrode size, and in the way they reported them. Because fNMES parameters impact the comfort and safety of volunteers, as well as its physiological (and psychological) effects, it is of paramount importance to establish recommendations of good practice and to ensure studies can be better compared and integrated. Here, we provide an introduction to fNMES, systematically review the existing literature focusing on the stimulation parameters used, and offer recommendations on how to safely and reliably deliver fNMES and on how to report the fNMES parameters to allow better cross-study comparison. In addition, we provide a free webpage, to easily visualise fNMES parameters and verify their safety based on current density. As an example of a potential application, we focus on the use of fNMES for the investigation of the facial feedback hypothesis.

Enhanced Empathic Pain by Facial Feedback

The facial feedback hypothesis states that feedback from cutaneous and muscular afferents affects our emotion. Based on the facial feedback hypothesis, the purpose of this study was to determine whether enhancing negative emotion by activating a facial muscle (corrugator supercilii) increases the intensity of cognitive and emotional components of empathic pain. We also assessed whether the muscle contraction changed the pupil size, which would indicate a higher level of arousal. Forty-eight individuals completed 40 muscular contraction and relaxation trials while looking at images of five male and five female patients with neutral and painful facial expressions, respectively. Participants were asked to rate (1) how much pain the patient was in, and (2) how unpleasant their own feelings were. We also examined their facial muscle activities and changes in pupil size. No significant differences in pain or unpleasantness ratings were detected for the neutral face between the two conditions; however, the pain and unpleasantness ratings for the painful face were considerably higher in the contraction than relaxation condition. The pupils were considerably larger in the contraction than relaxation condition for both the painful and neutral faces. Our findings indicate that, by strengthening the corrugator supercilii, facial feedback can affect both the cognitive evaluative and affective sharing aspects of empathic pain.

Pilot study of facial and bodily feedback

BACKGROUND

The modulation hypothesis of facial feedback has not adequately examined how combining facial expressions and bodily postures might influence our experience of emotional stimuli. This pilot study examined a new method for manipulating both face and body together, which is important in furthering our understanding of how face and body interact to influence emotional experiences in the real world.

METHODS

Using a within-subjects design, 30 participants viewed positive film clips under four conditions: (1) positive face with positive body (PP), (2) positive face with neutral body (PN), (3) neutral face with positive body (NP) and (4) neutral face with neutral body (NN). Measures of positive and negative affect were taken before and after each clip, to assess the subjective emotional experience.

RESULTS

Repeated-measures analysis of variance (ANOVA) was conducted to examine differences in the emotional experience under each condition. Post hoc pairwise comparisons demonstrated that positive affect in the PP condition was significantly higher than in the NP and NN conditions. There was no significant difference between the PP and NN conditions.

CONCLUSION

Whilst the study findings are difficult to interpret, this pilot study generated a number of important methodological learnings that are relevant to future research of this kind.

"When You're Smiling": How Posed Facial Expressions Affect Visual Recognition of Emotions

Facial imitation occurs automatically during the perception of an emotional facial expression, and preventing it may interfere with the accuracy of emotion recognition. In the present fMRI study, we evaluated the effect of posing a facial expression on the recognition of ambiguous facial expressions. Since facial activity is affected by various factors, such as empathic aptitudes, the Interpersonal Reactivity Index (IRI) questionnaire was administered and scores were correlated with brain activity. Twenty-six healthy female subjects took part in the experiment. The volunteers were asked to pose a facial expression (happy, disgusted, neutral), then to watch an ambiguous emotional face, finally to indicate whether the emotion perceived was happiness or disgust. As stimuli, blends of happy and disgusted faces were used. Behavioral results showed that posing an emotional face increased the percentage of congruence with the perceived emotion. When participants posed a facial expression and perceived a non-congruent emotion, a neural network comprising bilateral anterior insula was activated. Brain activity was also correlated with empathic traits, particularly with empathic concern, fantasy and personal distress. Our findings support the idea that facial mimicry plays a crucial role in identifying emotions, and that empathic emotional abilities can modulate the brain circuits involved in this process.

Integrating mind and body: Investigating differential activation of nodes of the default mode network

BACKGROUND

The default mode network (DMN) is a large-scale brain network tightly correlated with self and self-referential processing, activated by intrinsic tasks and deactivated by externally-directed tasks.

OBJECTIVE

In this study, we aim to investigate the novel approach of default mode activation during progressive muscle relaxation and examine whether differential activation patterns result from the movement of different body parts.

METHODS

We employed neuroimaging to investigate DMN activity during simple body movements, while performing progressive muscle relaxation. We focused on differentiating the neural response between facial movements and movements of other body parts.

RESULTS

Our results show that the movement of different body parts led to deactivation in several DMN nodes, namely the temporal poles, hippocampus, medial prefrontal cortex (mPFC), and posterior cingulate cortex. However, facial movement induced an inverted and selective positive BOLD pattern in some of these areas precisely. Moreover, areas in the temporal poles selective for face movement showed functional connectivity not only with the hippocampus and mPFC but also with the nucleus accumbens.

CONCLUSIONS

Our findings suggest that both conceptual and embodied self-related processes, including body movements during progressive muscle relaxation, may be mapped onto shared brain networks. This could enhance our understanding of how practices like PMR influence DMN activity and potentially offer insights to inform therapeutic strategies that rely on mindful body movements.

Law Enforcement Officers’ Ability to Recognize Emotions: The Role of Personality Traits and Basic Needs’ Satisfaction

Background: This study intended to explore the role of personality traits and basic psychological needs in law enforcement officers’ ability to recognize emotions: anger, joy, sadness, fear, surprise, disgust, and neutral. It was significant to analyze law enforcement officers’ emotion recognition and the contributing factors, as this field has been under-researched despite increased excessive force use by officers in many countries. Methods: This study applied the Big Five–2 (BFI-2), the Basic Psychological Needs Satisfaction and Frustration Scale (BPNSFS), and the Karolinska Directed Emotional Faces set of stimuli (KDEF). The data was gathered using an online questionnaire provided directly to law enforcement agencies. A total of 154 law enforcement officers participated in the study, 50.65% were females, and 49.35% were males. The mean age was 41.2 (age range = 22–61). In order to analyze the data, SEM and multiple linear regression methods were used. Results: This study analyzed variables of motion recognition, personality traits, and needs satisfaction and confirmed that law enforcement officers’ personality traits play a significant role in emotion recognition. Respondents’ agreeableness significantly predicted increased overall emotion recognition; conscientiousness predicted increased anger recognition; joy recognition was significantly predicted by extraversion, neuroticism, and agreeableness. This study also confirmed that law enforcement officers’ basic psychological needs satisfaction/frustration play a significant role in emotion recognition. Respondents’ relatedness satisfaction significantly predicted increased overall emotion recognition, fear recognition, joy recognition, and sadness recognition. Relatedness frustration significantly predicted decreased anger recognition, surprise recognition, and neutral face recognition. Furthermore, this study confirmed links between law enforcement officers’ personality traits, satisfaction/frustration of basic psychological needs, and emotion recognition, χ2 = 57.924; df = 41; p = 0.042; TLI = 0.929; CFI = 0.956; RMSEA = 0.042 [0.009–0.065]. Discussion: The findings suggested that agreeableness, conscientiousness, extraversion, and neuroticism play an essential role in satisfaction and frustration of relatedness needs, which, subsequently, link to emotion recognition. Due to the relatively small sample size, the issues of validity/reliability of some instruments, and other limitations, the results of this study should preferably be regarded with concern.

How humor is experienced: An embodied metaphor account

The study explores the humor-body association from the perspective of embodied cognition. According to the Conceptual Metaphor Theory, abstract concepts tend to be understood with concrete experiences through embodied mappings. Therefore, the current study attempts to investigate how humor, an understudied abstract concept, is perceived in the Chinese context by means of textual analysis and a behavioral experiment. Firstly, 6,500 entries of the corpus data related to laughter and humor in Chinese were used for the textual analysis. Extensive uses of embodied humor metaphors were found, which provided important linguistic evidence for the interaction between laughter, humor, and body. Secondly, a behavioral study was conducted based on some frequently-used embodied metaphorical expressions of humor (e.g., pěngfù dàxiào 捧腹大笑, meaning ‘to hold one’s sides laughing’) identified in the corpus. Specifically, the participants were instructed to either do embodied metaphor or non-metaphor actions as bodily primes (i.e., ‘holding one’s belly while bending forward and backward repeatedly’ vs. ‘turning one’s upper body from side to side with both hands on the back’) or perform no actions before completing the subsequent joke rating task and the mood rating task. Results showed that the participants who were primed with the embodied metaphor actions rated the jokes higher than those in the control groups who were primed with non-metaphor actions or had no primes. Also, there was no significant difference in the mood ratings across the groups. These findings suggest that embodied humor metaphors indeed affect humor experience and shape how humor is conceptualized. The current study supports not only the embodied view of humor understanding but also the conceptual metaphor account of abstract reasoning, which sheds new light on the theoretical development of the embodiment of abstract concepts.

Monitoring the effect of oxytocin on the neural sensitivity to emotional faces via frequency-tagging EEG: A double-blind, cross-over study

The neuropeptide oxytocin (OXT) is suggested to exert an important role in human social behaviors by modulating the salience of social cues. To date, however, there is mixed evidence whether a single dose of OXT can improve the behavioral and neural sensitivity for emotional face processing. To overcome difficulties encountered with classic event-related potential studies assessing stimulus-saliency, we applied frequency-tagging EEG to implicitly assess the effect of a single dose of OXT (24 IU) on the neural sensitivity for positive and negative facial emotions. Neutral faces with different identities were presented at 6 Hz, periodically interleaved with an expressive face (angry, fearful, and happy, in separate sequences) every fifth image (i.e., 1.2 Hz oddball frequency). These distinctive frequency tags for neutral and expressive stimuli allowed direct and objective quantification of the neural expression-categorization responses. The study involved a double-blind, placebo-controlled, cross-over trial with 31 healthy adult men. Contrary to our expectations, we did not find an effect of OXT on facial emotion processing, neither at the neural, nor at the behavioral level. A single dose of OXT did not evoke social enhancement in general, nor did it affect social approach-avoidance tendencies. Possibly ceiling performances in facial emotion processing might have hampered further improvement.

Audience facial expressions detected by automated face analysis software reflect emotions in music

An abundance of studies on emotional experiences in response to music have been published over the past decades, however, most have been carried out in controlled laboratory settings and rely on subjective reports. Facial expressions have been occasionally assessed but measured using intrusive methods such as facial electromyography (fEMG). The present study investigated emotional experiences of fifty participants in a live concert. Our aims were to explore whether automated face analysis could detect facial expressions of emotion in a group of people in an ecologically valid listening context, to determine whether emotions expressed by the music predicted specific facial expressions and examine whether facial expressions of emotion could be used to predict subjective ratings of pleasantness and activation. During the concert, participants were filmed and facial expressions were subsequently analyzed with automated face analysis software. Self-report on participants’ subjective experience of pleasantness and activation were collected after the concert for all pieces (two happy, two sad). Our results show that the pieces that expressed sadness resulted in more facial expressions of sadness (compared to happiness), whereas the pieces that expressed happiness resulted in more facial expressions of happiness (compared to sadness). Differences for other facial expression categories (anger, fear, surprise, disgust, and neutral) were not found. Independent of the musical piece or emotion expressed in the music facial expressions of happiness predicted ratings of subjectively felt pleasantness, whilst facial expressions of sadness and disgust predicted low and high ratings of subjectively felt activation, respectively. Together, our results show that non-invasive measurements of audience facial expressions in a naturalistic concert setting are indicative of emotions expressed by the music, and the subjective experiences of the audience members themselves.

Embodiment: I sat, I felt, I performed - Posture effects on mood and cognitive performance

Previous embodiment findings indicate a relationship between physical posture and mood states, suggesting upright postures induce positive mood states. Findings also showed a relationship between moods and cognitive performance. While positive mood states were found to be related to increased processing speed, negative mood states were associated with higher processing accuracy in cognitive task performance. This implies that posture may affect the aforementioned sub-aspects of cognitive performance via mood states. Additionally, most studies on posture effects rely on explicit posture manipulation. With that in mind, our research explores the effects of implicitly manipulated postures on processing speed and accuracy and whether these effects are mediated by general mood. The results revealed that subjects in our sample (N = 82, M = 23.09years) who adopted an upright posture showed a more positive general mood (d = 0.50) and higher processing speed (d = 0.42) compared to those in stooped postures. Surprisingly, no differences in processing accuracy were found. There was no evidence of the proposed mediation in our data.

Having Difficulties Reading the Facial Expression of Older Individuals? Blame It on the Facial Muscles, Not the Wrinkles

Previous studies have found it is more difficult identifying an emotional expression displayed by an older than a younger face. It is unknown whether this is caused by age-related changes such as wrinkles and folds interfering with perception, or by the aging of facial muscles, potentially reducing the ability of older individuals to display an interpretable expression. To discriminate between these two possibilities, participants attempted to identify facial expressions under different conditions. To control for the variables (wrinkles/folds vs facial muscles), we used Generative Adversarial Networks to make faces look older or younger. Based upon behavior data collected from 28 individuals, our model predicts that the odds of correctly identifying the expressed emotion of a face reduced 16.2% when younger faces (condition 1) are artificially aged (condition 3). Replacing the younger faces with natural old-looking faces (Condition 2), however, results in an even stronger effect (odds of correct identification decreased by 50.9%). Counterintuitively, making old faces (Condition 2) look young (Condition 4) results in the largest negative effect (odds of correct identification decreased by 74.8% compared with natural young faces). Taken together, these results suggest that both age-related decline in the facial muscles' ability to express facial emotions and age-related physical changes in the face, explain why it is difficult to recognize facial expressions from older faces; the effect of the former, however, is much stronger than that of the latter. Facial muscle exercises, therefore, might improve the capacity to convey facial emotional expressions in the elderly.

Expressions of emotions across species

What are emotions and how should we study them? These questions give rise to ongoing controversy amongst scientists in the fields of neuroscience, psychology and philosophy, and have resulted in different views on emotions [1-6]. In this review, we define emotions as functional states that bear essential roles in promoting survival and thus have emerged through evolution. Emotions trigger behavioral, somatic, hormonal, and neurochemical reactions, referred to as expressions of emotion. We discuss recent studies on emotion expression across species and highlight emerging common principles. We argue that detailed and multidimensional analyses of emotion expressions are key to develop biology-based definitions of emotions and to reveal their neuronal underpinnings.

Exploring the mechanisms responsible for the modulating role of frowning in emotional reasoning: An ERP study

Studies show that emotions impact reasoning, and that emotions are embodied. A recent study revealed that emotions embodied in facial expressions can modulate the impact of emotional content on reasoning accuracy. In the current study, we aimed to explore the mechanisms responsible for the impact of frowning on emotional reasoning using electrophysiology. We examined two reasoning-related ERPs: the N400 related to inference process and the N2 related to conflict detection. We also measured the LPP, associated with sustained attention to emotional stimuli. Twenty-six participants completed a reasoning task with emotional content while we recorded their brain activity with electroencephalography. In one block, they were instructed to solve syllogisms while voluntarily frowning. In another block, they were asked to solve syllogisms while contracting a non-facial muscle. Results revealed that frowning influenced sustained attention towards emotional stimuli, as measured through LPP. Frowning also showed a trend for a deleterious effect on the inference process measured through the N400. In line with the dual process models, this suggests that frowning impacts sustained attention, but surprisingly it might also impact Type 2 processes. This study provides useful insight regarding the link between reasoning and emotions in the body.

Representation of the brain network by electroencephalograms during facial expressions

BACKGROUND

Facial expressions, such as smiling and anger, cause many physical and psychological effects in the body, known as 'embodied emotions' or 'facial feedback theory.' In the clinical application of this theory in certain diseases, such as autism and depression, treatments such as forcing patients to smile have been used. However, the neural mechanisms underlying the representation of facial expressions remain unclear.

NEW METHOD

We proposed a method to construct brain networks based on the time course of the synchronization likelihood and determine the effects of various facial expressions on the situation using visual stimulus of faces. This method was applied to analyze electroencephalographic (EEG) data recorded during the recognition and representation of various positive and negative facial expressions. The brain networks were constructed based on the EEG data recorded in 11 healthy participants.

RESULTS

Channel sets from brain networks during unsymmetrical smiling expressions (i.e., only the right or left side) were highly linearly symmetrical. Channel sets from brain networks during negative facial expressions (i.e., anger and sadness) and symmetrical smiling expressions (i.e., smiling with an opened or closed mouth) were similar.

COMPARISON WITH EXISTING METHODS

While we obtained brain networks based on time course EEG correlations throughout the experiment, existing methods can analyze EEG data only at a certain time point.

CONCLUSIONS

The comparisons of different facial expressions could be used to identify the side of the facial muscles used while smiling and to determine how similar brain networks are induced by positive and negative facial expressions.

Investigating automatic emotion processing in boys with autism via eye tracking and facial mimicry recordings

Difficulties in automatic emotion processing in individuals with autism spectrum disorder (ASD) might remain concealed in behavioral studies due to compensatory strategies. To gain more insight in the mechanisms underlying facial emotion recognition, we recorded eye tracking and facial mimicry data of 20 school-aged boys with ASD and 20 matched typically developing controls while performing an explicit emotion recognition task. Proportional looking times to specific face regions (eyes, nose, and mouth) and face exploration dynamics were analyzed. In addition, facial mimicry was assessed. Boys with ASD and controls were equally capable to recognize expressions and did not differ in proportional looking times, and number and duration of fixations. Yet, specific facial expressions elicited particular gaze patterns, especially within the control group. Both groups showed similar face scanning dynamics, although boys with ASD demonstrated smaller saccadic amplitudes. Regarding the facial mimicry, we found no emotion specific facial responses and no group differences in the responses to the displayed facial expressions. Our results indicate that boys with and without ASD employ similar eye gaze strategies to recognize facial expressions. Smaller saccadic amplitudes in boys with ASD might indicate a less exploratory face processing strategy. Yet, this slightly more persistent visual scanning behavior in boys with ASD does not imply less efficient emotion information processing, given the similar behavioral performance. Results on the facial mimicry data indicate similar facial responses to emotional faces in boys with and without ASD. LAY SUMMARY: We investigated (i) whether boys with and without autism apply different face exploration strategies when recognizing facial expressions and (ii) whether they mimic the displayed facial expression to a similar extent. We found that boys with and without ASD recognize facial expressions equally well, and that both groups show similar facial reactions to the displayed facial emotions. Yet, boys with ASD visually explored the faces slightly less than the boys without ASD.

Mood and emotional disorders associated with parkinsonism, Huntington disease, and other movement disorders

This chapter provides a review of mood, emotional disorders, and emotion processing deficits associated with diseases that cause movement disorders, including Parkinson's disease, Lewy body dementia, multiple system atrophy, progressive supranuclear palsy, corticobasal degeneration, frontotemporal dementia with parkinsonism, Huntington's disease, essential tremor, dystonia, and tardive dyskinesia. For each disorder, a clinical description of the common signs and symptoms, disease progression, and epidemiology is provided. Then the mood and emotional disorders associated with each of these diseases are described and discussed in terms of clinical presentation, incidence, prevalence, and alterations in quality of life. Alterations of emotion communication, such as affective speech prosody and facial emotional expression, associated with these disorders are also discussed. In addition, if applicable, deficits in gestural and lexical/verbal emotion are reviewed. Throughout the chapter, the relationships among mood and emotional disorders, alterations of emotional experiences, social communication, and quality of life, as well as treatment, are emphasized.

Body Matters in Emotion: Restricted Body Movement and Posture Affect Expression and Recognition of Status-Related Emotions

Embodiment theory suggests that we use our own body and experiences to simulate information from other people’s bodies and faces to understand their emotions. A natural consequence of embodied theory is that our own current position and state contributes to this emotional processing. Testing non-disabled individuals, we investigated whether restricted body posture and movement influenced the production and recognition of nonverbal, dynamic emotional displays in able-bodied participants. In Experiment 1, participants were randomly assigned to either unrestricted or wheelchair-restricted (sitting, torso restrained) groups and nonverbally expressed six emotions (disgust, happiness, anger, fear, embarrassment, and pride) while being videotaped. After producing each emotion, they rated their confidence regarding how effectively they communicated that emotion. Videotaped emotional displays were coded for face, body, and face + body use. Based on naïve coders’ scores, both unrestricted and wheelchair-restricted groups produced emotionally congruent face and body movements and both groups were equally confident in their communication effectiveness. Using videos from Experiment 1, Experiment 2 tested non-disabled participants’ ability to recognize emotions from unrestricted and wheelchair-restricted displays. Wheelchair-restricted displays showed an overall decline in recognition accuracy, but recognition was selectively impaired for the dominance-related emotions of disgust and anger. Consistent with embodied emotion theory, these results emphasize the importance of the body for emotion communication and have implications for social interactions between individuals with and without physical disabilities. Changes in nonverbal emotion signals from body restrictions may influence social interactions that rely on the communication of dominance-related social emotions.

Efficiency of Illusory Choice Used as a Variant of Situation Selection for Regulating Emotions: Reduction of Positive Experience But Preservation of Physiological Downregulation

Situation selection is an emotion regulation strategy consisting in choosing a future emotional situation. Past research showed that Situation selection triggers a decrease in negative experience, exocrine reactions and respiratory activity, while maintaining stable positive experience. In this study, we wanted to replicate these observations and test emotional responses that follow an Illusory choice, i.e., when the chosen situation is not available and replaced by another. Sixty-eight participants watched emotional pictures, either in a condition in which the images were imposed, or in a condition in which they could perform a choice. In these latter trials, participants saw either the chosen option (Situation selection) or the non-selected option (Illusory choice). Continuous recordings of experience and physiological arousal showed that, unlike Situation selection, Illusory choice decreased positive experience but not negative experience. Strikingly, however, we showed that having the choice decreased skin conductance and respiratory arousal, regardless of whether the choice was respected or not. These results have important implications regarding emotion regulation through Situation selection, since having the choice about the upcoming emotional situation, no matter if we really end up in this situation, gives a sense of control that may be sufficient to alleviate physiological responses to stressors.

OnabotulinumtoxinA for the treatment of major depressive disorder: a phase 2 randomized, double-blind, placebo-controlled trial in adult females

This 24-week double-blind placebo-controlled multicenter randomized phase 2 trial evaluated efficacy and safety of onabotulinumtoxinA (onabotA; BOTOX) vs. placebo for major depressive disorder (MDD) [NCT02116361]. Primary endpoint was the change in Montgomery-Åsberg Depression Rating Scale (MADRS); secondary endpoints were Clinical Global Impressions-Severity and 17-item Hamilton Depression Rating Scale at week 6. A total of 255 adult females were treated. OnabotA 30 U approached significance compared to placebo on MADRS (mixed-effect model repeated measures least-squares mean difference: -3.7; P = 0.053) and reached significance [least-squares mean differences: -3.6 to -4.2; P < 0.05 (two-sided)] at weeks 3 and 9. Secondary endpoints were also significant at several time points. At week 6, onabotA 50 U did not separate from placebo in any parameters. OnabotA was generally well-tolerated: the only treatment-emergent adverse events reported in ≥5% in either onabotA group, and more than matching placebo were headache, upper respiratory infection, and eyelid ptosis. OnabotA 30 U, administered in a standardized injection pattern in a single session, had a consistent efficacy signal across multiple depression symptom scales for 12 or more weeks. OnabotA 30 U/placebo MADRS differences of (observed ANCOVA) ≥4.0 points (up to week 15) and ≥2.0 points (weeks 18-24) agree with the 2-point change threshold considered clinically relevant in MDD. OnabotA is a local therapy and is not commonly associated with systemic effects of conventional antidepressants and may represent a novel treatment option for MDD.

My body, your emotions: Viscerosomatic modulation of facial expression discrimination

Interoception reflects the ability to observe one's innermost bodily states. Here, we assessed whether interoceptive accuracy (IA) is related to the empathic ability to discriminate others' emotions. Participants (N = 111) completed a heartbeat tracking task, as well as an emotional go/no-go task with fearful and disgusted faces. Empathic facial mimicry during the go/no-go task was measured using electromyography (EMG) of the Corrugator Supercilii muscle. Higher IA was associated with higher perceptual sensitivity for emotional faces but was unrelated to response bias. Individuals higher in IA had stronger coupling between facial EMG and task performance. IA and facial EMG were associated with Go but not with NoGo trials, consistent with a specific modulation of perceptual sensitivity. These results suggest that tuning into one's own viscerosomatic signals relates to empathic mimicry and perception of others' emotional states.

Evaluating the interplay between subclinical levels of mental health symptoms and coordination dynamics

Viewed under the broad theoretical umbrella of an embodied-embedded approach to psychological activity, body movements can be seen to play an essential role in shaping social interaction. Of note, research concerning the embodiment of social cognition has documented key differences in non-verbal behaviour during social interaction for individuals diagnosed with a range of disorders, including social anxiety disorder and autism spectrum disorder. The present work sets out to extend these findings by better understanding the interplay between subclinical variation in psychopathology and social-motor coordination, a key component of effective interaction. We asked participants, in pairs, to swing hand-held pendula that varied in their intrinsic movement characteristics. Extending previous clinically oriented work (Varlet et al., 2014, Frontiers in Behavioral Neuroscience, 8, 29), our results indicated that subclinical variation in mental health status was predictive of disruption to the patterns of coordination dynamics that characterize effective social exchange. This work provides further evidence for the utility of theorizing social interaction as a self-organizing dynamical system and strengthens support for the claim that disruption to interpersonal coordination may act as an embodied-embedded marker of variation in mental health.

Empathic Understanding: Benefits of Perspective-Taking and Facial Mimicry Instructions are Mediated by Self-Other Overlap

The current study sought to better understand the utility of two strategies - perspective-taking and facial mimicry - proposed to increase empathic responding. Thirty-seven female participants were presented an interpersonal situation (a betrayal) that would elicit the use of empathic responding to achieve conflict resolution between friends. Each participant was given instructions to partake in either perspective-taking, facial mimicry, or to remain neutral (control condition). The results demonstrated that individuals who engaged in perspective-taking reported significantly higher state empathy than the control condition, but there was no significant difference in state empathy between the mimicry and control condition. Also, those who engaged in either strategy reported significantly higher self-other overlap relative to those not instructed to engage in a particular strategy. Importantly, self-other overlap mediated the association between the instructional sets and state empathy. Both strategies are arguably means of enhancing interpersonal understanding.

The regulatory effect of choice in Situation Selection reduces experiential, exocrine and respiratory arousal for negative emotional stimulations

Situation selection is a seldom studied emotion regulation strategy that entails choosing an upcoming emotional situation. Two mechanisms may drive its regulatory effect on emotional responses. One relates to the evaluation of the chosen option, people generally selecting the most positive. The other one implies that having the choice regarding the upcoming emotional situation is already regulatory, independently of what we choose. This research aimed at investigating this latter hypothesis. In a within-subject design, we compared emotional responses of 65 participants when they viewed negative and positive images they could select (use of Situation selection) vs. when they were imposed the exact same images (Situation selection not used). Results show that having the choice in negative contexts decreased negative experience, skin conductance, and respiration reactivity, while enhancing expressivity and cardiovascular reactivity. In positive contexts, choosing generally reinforced the image calming effect. Thus, contrary to other strategies that are efficient for negative but usually impair positive reactions (e.g., distraction), Situation selection may be used widely to reduce negative experience, while avoiding depletion of positive responses. This is particularly notable in emotion experience. Remarkably, these effects are not driven by the content of the situations, but by the act of choosing itself.

How the Experience of Emotion is Modulated by Facial Feedback

The facial feedback hypothesis states that facial actions modulate subjective experiences of emotion. Using the voluntary facial action technique, in which the participants react with instruction induced smiles and frowns when exposed to positive and negative emotional pictures and then rate the pleasantness of these stimuli, four questions were addressed in the present study. The results in Experiment 1 demonstrated a feedback effect because participants experienced the stimuli as more pleasant during smiling as compared to when frowning. However, this effect was present only during the critical actions of smiling and frowning, with no remaining effects after 5 min or after 1 day. In Experiment 2, feedback effects were found only when the facial action (smile/frown) was incongruent with the presented emotion (positive/negative), demonstrating attenuating but not enhancing modulation. Finally, no difference in the intensity of produced feedback effect was found between smiling and frowning, and no difference in feedback effect was found between positive and negative emotions. In conclusion, facial feedback appears to occur mainly during actual facial actions, and primarily attenuate ongoing emotional states.

Emotional Mimicry Beyond the Face?

Emotional mimicry—quick and spontaneous matching of another’s expressions—is a well-documented phenomenon that is associated with numerous social outcomes. Although the mechanisms underlying mimicry are not fully understood, there is growing awareness that it is more than a one-to-one motor matching of others’ expressions and may be the result of neural simulation. If true, it is possible that mimicry could extend to other parts of the body, even in the absence of visual information from that body part. Indeed, we found that passively viewing anger and fear expressions, without accompanying information from the body, voice or other channels, produced both facial mimicry and corresponding responses in arm muscles that make a fist or a defensive posture. This suggests that observers simulated observed expressions and that activity may have spilled over to other areas to create a body response.

The effect of facial feedback on the evaluation of statements describing everyday situations and the role of awareness

According to theories of embodiment enacting a smile or a frown can positively or negatively influence one's evaluations, even without awareness of one's facial activity. While some previous studies found evidence for facial feedback effects, recent replication attempts could not confirm these findings. Are our decisions throughout the day amenable to the state of our facial muscles? We tested the effect of smiling and frowning on the evaluation of emotional sentences describing everyday situations. While most previous studies based their assessment of awareness on verbal debriefing interviews without explicitly defined criteria, we employed a written debriefing questionnaire in order to avoid potential bias when identifying participants' awareness. Our results indicate that smiling/frowning increased/decreased sentence ratings only for participants aware of their expressions. This emphasizes the importance of more rigorous awareness tests in facial feedback studies. Our results support the view that facial feedback cannot necessarily influence us without conscious mediation.

Spontaneous Facial Actions Map onto Emotional Experiences in a Non-social Context: Toward a Component-Based Approach

While numerous studies have examined the relationships between facial actions and emotions, they have yet to account for the ways that specific spontaneous facial expressions map onto emotional experiences induced without expressive intent. Moreover, previous studies emphasized that a fine-grained investigation of facial components could establish the coherence of facial actions with actual internal states. Therefore, this study aimed to accumulate evidence for the correspondence between spontaneous facial components and emotional experiences. We reinvestigated data from previous research which secretly recorded spontaneous facial expressions of Japanese participants as they watched film clips designed to evoke four different target emotions: surprise, amusement, disgust, and sadness. The participants rated their emotional experiences via a self-reported questionnaire of 16 emotions. These spontaneous facial expressions were coded using the Facial Action Coding System, the gold standard for classifying visible facial movements. We corroborated each facial action that was present in the emotional experiences by applying stepwise regression models. The results found that spontaneous facial components occurred in ways that cohere to their evolutionary functions based on the rating values of emotional experiences (e.g., the inner brow raiser might be involved in the evaluation of novelty). This study provided new empirical evidence for the correspondence between each spontaneous facial component and first-person internal states of emotion as reported by the expresser.

Facial emotion recognition, theory of mind and the role of facial mimicry in depression

BACKGROUND

This study examined whether acutely (aMDD) and remitted depressed patients (rMDD) show deficits in the two aspects of social cognition - facial emotion recognition (FER) and reasoning - when using ecologically valid material. Furthermore, we examined whether reduced facial mimicry mediates the association between depressive symptoms and FER, and whether FER deficits and reasoning deficits are associated.

METHOD

In 42 aMDD, 43 rMDD, and 39 healthy controls (HC) FER was assessed using stimuli from the Amsterdam Dynamic Facial Expression Set, reasoning by the Movie for the Assessment of Social Cognition. Furthermore, the activity of Zygomaticus Major and Corrugator supercilii were recorded.

RESULTS

aMDD recognized happy faces less accurately, were less confident recognizing happiness and anger and found it more difficult to recognize happiness, anger and fear than HC. rMDD were less confident recognizing anger and found it more difficult to recognize happiness, anger and fear than HC. Reduced mimicry did not explain FER deficits. aMDD but not rMDD showed impaired reasoning.

LIMITATIONS

The stimulus material was comparably easy to decode. Therefore, it is possible that the FER deficits of aMDD and rMDD patients are more pronounced than demonstrated in this study.

CONCLUSIONS

aMDD show deficits in FER and reasoning, whereas rMDD only show mild impairments in the recognition of emotional expressions. There must be other processes - besides mimicry - that serve the accurate recognition of emotional facial expressions.

Upright posture improves affect and fatigue in people with depressive symptoms

BACKGROUND AND OBJECTIVES

Slumped posture is a diagnostic feature of depression. While research shows upright posture improves self-esteem and mood in healthy samples, little research has investigated this in depressed samples. This study aimed to investigate whether changing posture could reduce negative affect and fatigue in people with mild to moderate depression undergoing a stressful task.

METHODS

Sixty-one community participants who screened positive for mild to moderate depression were recruited into a study purportedly on the effects of physiotherapy tape on cognitive function. They were randomized to sit with usual posture or upright posture and physiotherapy tape was applied. Participants completed the Trier Social Stress Test speech task. Changes in affect and fatigue were assessed. The words spoken by the participants during their speeches were analysed.

RESULTS

At baseline, all participants had significantly more slumped posture than normative data. The postural manipulation significantly improved posture and increased high arousal positive affect and fatigue compared to usual posture. The upright group spoke significantly more words than the usual posture group, used fewer first person singular personal pronouns, but more sadness words. Upright shoulder angle was associated with lower negative affect and lower anxiety across both groups.

LIMITATIONS

The experiment was only brief and a non-clinical sample was used.

CONCLUSIONS

This preliminary study suggests that adopting an upright posture may increase positive affect, reduce fatigue, and decrease self-focus in people with mild-to-moderate depression. Future research should investigate postural manipulations over a longer time period and in samples with clinically diagnosed depression.

Facial Feedback and Social Input: Effects on Laughter and Enjoyment in Children with Autism Spectrum Disorders

Both social input and facial feedback appear to be processed differently by individuals with autism spectrum disorder (ASD). We tested the effects of both of these types of input on laughter in children with ASD. Sensitivity to facial feedback was tested in 43 children with ASD, aged 8-14 years, and 43 typically developing children matched for mental age (6-14), in order to examine whether children with ASD use bodily feedback as an implicit source of information. Specifically, children were asked to view cartoons as they normally would (control condition), and while holding a pencil in their mouth forcing their smiling muscles into activation (feedback condition) while rating their enjoyment of the cartoons. The authors also explored the effects of social input in children with ASD by investigating whether the presence of a caregiver or friend (companion condition), or the presence of a laugh track superimposed upon the cartoon (laugh track condition) increased the children's self-rated enjoyment of cartoons or the amount of positive affect they displayed. Results showed that the group with ASD was less affected by all three experimental conditions, but also that group differences seemed to have been driven by one specific symptom of ASD: restricted range of affect. The strong relationship between restricted affect and insensitivity to facial feedback found in this study sheds light on the implications of restricted affect for social development in ASD.

Emotional facial activation induced by unconsciously perceived dynamic facial expressions

Do facial expressions of emotion influence us when not consciously perceived? Methods to investigate this question have typically relied on brief presentation of static images. In contrast, real facial expressions are dynamic and unfold over several seconds. Recent studies demonstrate that gaze contingent crowding (GCC) can block awareness of dynamic expressions while still inducing behavioural priming effects. The current experiment tested for the first time whether dynamic facial expressions presented using this method can induce unconscious facial activation. Videos of dynamic happy and angry expressions were presented outside participants' conscious awareness while EMG measurements captured activation of the zygomaticus major (active when smiling) and the corrugator supercilii (active when frowning). Forced-choice classification of expressions confirmed they were not consciously perceived, while EMG revealed significant differential activation of facial muscles consistent with the expressions presented. This successful demonstration opens new avenues for research examining the unconscious emotional influences of facial expressions.

The Dissociation of Emotion Expression from Emotion Experience: A Personality Perspective

When we want to know what others are feeling, we look to the face for clues. However, individual differences matter: Some faces are more expressive than others. Do both emotion experience and dispositional expressivity predict emotion expression? Based on an analysis of display rules, the authors hypothesized that expressivity would moderate the relation between experience and expression for negative, but not for positive, emotion. Study 1 examined the relation between habitual emotion experience and peer-rated expressive behavior and showed the predicted moderator effect for negative emotion: Experience was related to expression only for dispositionally high-expressivity participants, not for low-expressivity participants. For positive emotion, however, experience was related to expression for both groups. Study 2 replicated these findings using momentary emotion experience and objectively coded expressive behavior during films that elicited amusement and sadness. Results are interpreted in terms of low-expressivity individuals' propensity to dynamically regulate negative emotion-expressive behavior.

Emotion Regulation through Movement: Unique Sets of Movement Characteristics are Associated with and Enhance Basic Emotions

We have recently demonstrated that motor execution, observation, and imagery of movements expressing certain emotions can enhance corresponding affective states and therefore could be used for emotion regulation. But which specific movement(s) should one use in order to enhance each emotion? This study aimed to identify, using Laban Movement Analysis (LMA), the Laban motor elements (motor characteristics) that characterize movements whose execution enhances each of the basic emotions: anger, fear, happiness, and sadness. LMA provides a system of symbols describing its motor elements, which gives a written instruction (motif) for the execution of a movement or movement-sequence over time. Six senior LMA experts analyzed a validated set of video clips showing whole body dynamic expressions of anger, fear, happiness and sadness, and identified the motor elements that were common to (appeared in) all clips expressing the same emotion. For each emotion, we created motifs of different combinations of the motor elements common to all clips of the same emotion. Eighty subjects from around the world read and moved those motifs, to identify the emotion evoked when moving each motif and to rate the intensity of the evoked emotion. All subjects together moved and rated 1241 motifs, which were produced from 29 different motor elements. Using logistic regression, we found a set of motor elements associated with each emotion which, when moved, predicted the feeling of that emotion. Each emotion was predicted by a unique set of motor elements and each motor element predicted only one emotion. Knowledge of which specific motor elements enhance specific emotions can enable emotional self-regulation through adding some desired motor qualities to one's personal everyday movements (rather than mimicking others' specific movements) and through decreasing motor behaviors which include elements that enhance negative emotions.

Gender differences in the neural network of facial mimicry of smiles--An rTMS study

Under theories of embodied emotion, exposure to a facial expression triggers facial mimicry. Facial feedback is then used to recognize and judge the perceived expression. However, the neural bases of facial mimicry and of the use of facial feedback remain poorly understood. Furthermore, gender differences in facial mimicry and emotion recognition suggest that different neural substrates might accompany the production of facial mimicry, and the processing of facial feedback, in men and women. Here, repetitive transcranial magnetic stimulation (rTMS) was applied to the right primary motor cortex (M1), the right primary somatosensory cortex (S1), or, in a control condition, the vertex (VTX). Facial mimicry of smiles and emotion judgments were recorded in response to video clips depicting changes from neutral or angry to happy facial expressions. While in females rTMS over M1 and S1 compared to VTX led to reduced mimicry and, in the case of M1, delayed detection of smiles, there was no effect of TMS condition for males. We conclude that in female participants M1 and S1 play a role in the mimicry and in the use of facial feedback for accurate processing of smiles.

Mapping the emotional landscape: The role of specific emotions in conceptual categorization

Although researchers generally subscribe to the opinion that emotions play a critical role in cognition, very few (see Niedenthal, Halberstadt, & Innes-Ker, 1999) have examined the specific interaction between the emotional state of the perceiver and the emotional meaning of stimuli in conceptual categorization - an important aspect of "higher-level" cognition. Niedenthal et al. (1999) advanced a fine-grained theory of emotional response categorization, arguing that emotional states increase the tendency to categorize concepts into a predictable set of emotional response categories characterized by the common, distinct emotional responses elicited by the concepts. Based on the pioneering work of Niedenthal et al., we further argued that (1) the specific emotion experienced by the individual should selectively facilitate the categorization of concepts associated with the same emotion, (2) both in terms of category inclusion and category exclusion, and (3) this facilitation effect should not be contingent on the awareness of the emotional state. In three experiments, participants were induced to experience different emotional states through movies or a facial-feedback manipulation. They judged whether or not a target concept belonged to the same category as the two comparison concepts. Some of the concept triads shared emotional associations, while others didn't. Results showed that emotive participants had a greater tendency than those in a neutral mood to group concepts according to their emotional associations, and to distinguish concepts with different emotional associations. They were also more efficient in categorizing concepts that had specific emotional meaning corresponding to their own emotional state than to other emotional concepts. Furthermore, participants posing a disgust expression without their knowledge showed higher tendency to categorize concepts according to their relevance to disgust. Implications and potential applications of the findings were discussed.