Corrugator Supercilii Research Articles

Embodied power: Specific facial muscles automatically respond to power-related information processing

Derived from embodiment approaches, we tested the assumption that specific facial muscle contractions are simulated upon the categorization of power-related words. For this, we used an interference task that required participants to categorize trait adjectives according to their underlying power. Response latencies of contractions of either the corrugator supercilii (pulls the eyebrows together) or the depressor anguli oris muscle (pulls the corners of the mouth downwards) were assessed. In two experiments, we expected and found that the speed of facial responses crucially depends on whether a high power or low power adjective was categorized. More precisely, corrugator responses were faster to high power adjectives whereas depressor responses were faster to low power adjectives. These findings support the assumption that the meaning of power is at least partially grounded in motor representations underlying specific facial expressions.

Understanding Facial Muscle Aging: A Surface Electromyography Study.

Facial aging is a multifactorial process that involves all tissues of the face, including skin, muscles, fat, ligaments, and bone. Whereas robust evidence is available for age-related changes of bone and facial fat, the influence of age on facial muscle activity is poorly understood. The objective of this study was to investigate the motor unit action potential of facial muscles by utilizing surface-derived, noninvasive electromyography in young and old healthy volunteers. The study investigated a total of 32 healthy volunteers with a mean [standard deviation] age of 42.6 [19.6] years (range, 21-82 years) and a mean BMI of 23.9 [2.7] kg/m2 (range, 18.5-29.7 kg/m2) by performing surface-derived, noninvasive facial electromyography. Nine facial muscles were investigated bilaterally, resulting in a total of 1632 measurements of the signal, baseline noise, and signal-to-noise ratio of these muscles. The results of the study revealed that age does not significantly influence the signal (P = 0.234), the baseline noise (P = 0.225), or the signal-to-noise ratio (P = 0.432) of younger individuals (<30 years) vs older individuals (>50 years) in a gender- and BMI-matched statistical model. Exceptions were the zygomaticus major muscle (reduced activity), procerus muscle (increased activity), and corrugator supercilii muscle (increased activity). The results of this facial electromyography study may help to increase the understanding of facial aging. Future studies need to reproduce the results presented herein to further increase our understanding of facial aging.

Facing the enemy: Spontaneous facial reactions towards suffering opponents.

The suffering of an opponent is an important social affective cue that modulates how aggressive interactions progress. To investigate the affective consequences of opponent suffering on a revenge seeking individual, two experiments (total N=82) recorded facial muscle activity while participants observed the reaction of a provoking opponent to a (retaliatory) sound punishment in a laboratory aggression task. Opponents reacted via prerecorded videos either with facial displays of pain, sadness, or neutrality. Results indicate that participants enjoyed seeing the provocateur suffer: indexed by a coordinated muscle response featuring an increase in zygomaticus major (and orbicularis oculi muscle) activation accompanied by a decrease in corrugator supercilii activation. This positive facial reaction was only shown while a provoking opponent expressed pain. Expressions of sadness, and administration of sound blasts to nonprovoking opponents, did not modulate facial activity. Overall, the results suggest that revenge-seeking individuals enjoy observing the offender suffer, which could represent schadenfreude or satisfaction of having succeeded in the retaliation goal.

Associations between Cognitive Concepts of Self and Emotional Facial Expressions with an Emphasis on Emotion Awareness

Recognising our own and others’ emotions is vital for healthy social development. The aim of the current study was to determine how emotions related to the self or to another influence behavioural expressions of emotion. Facial electromyography (EMG) was used to record spontaneous facial muscle activity in nineteen participants while they passively viewed negative, positive and neutral emotional pictures during three blocks of referential instructions. Each participant imagined themself, another person or no one experiencing the emotional scenario, with the priming words “You”, “Him” or “None” presented before each picture for the respective block of instructions. Emotion awareness (EA) was also recorded using the TAS-20 alexithymia questionnaire. Corrugator supercilii (cs) muscle activity increased significantly between 500 and 1000 ms post stimulus onset during negative and neutral picture presentations, regardless of ownership. Independent of emotion, cs activity was greatest during the “no one” task and lowest during the “self” task from less than 250 to 1000 ms. Interestingly, the degree of cs activation during referential tasks was further modulated by EA. Low EA corresponded to significantly stronger cs activity overall compared with high EA, and this effect was even more pronounced during the “no one” task. The findings suggest that cognitive processes related to the perception of emotion ownership can influence spontaneous facial muscle activity, but that a greater degree of integration between higher cognitive and lower affective levels of information may interrupt or suppress these behavioural expressions of emotion.

Respecting upper facial anatomy for treating the glabella with neuromodulators to avoid medial brow ptosis-A refined 3-point injection technique.

Current injection algorithms for treating the glabella rely on a five- or seven-point injection technique with possible medial eyebrow ptosis and lateral eyebrow elevation as undesirable outcomes. The objective of this study was to investigate the efficacy and safety profile of a refined 3-point injection technique targeting horizontal and vertical glabellar lines. A total of n=105 patients (27 males and 78 females) with a mean age of 40.90±9.2years were investigated. The injection technique relied on targeting the muscular origin of the procerus and the corrugator supercilii muscles exclusively. The time of effect onset and the injection-related outcome 120days after the treatment was evaluated using the 5-point glabellar line severity scale. The onset of the neuromodulator effect was on average 3.5±1.5days. There was no statistically significant difference in the amplitude of movement before or 14days after the treatment with 2.99±4.4mm vs. 3.39±3.6mm (p=0.149) for the medial head of the eyebrow and with 3.18±4.7mm vs. 3.33±4.3mm (p=0.510) for the lateral head of the eyebrow, respectively. Incorporating anatomic concepts into clinical practice for glabellar frown line neuromodulator treatments with the investigated 3-point injection technique resulted in the absence of adverse events like eyebrow ptosis, upper eyelid ptosis, medial eyebrow ptosis, and lateral frontalis hyperactivity. This technique demonstrated efficacy throughout the 4-month study period.

The role of intolerance of uncertainty in the acquisition and extinction of reward.

Individuals, who score high in self-reported intolerance of uncertainty (IU), tend to find uncertainty anxiety-provoking. IU has been reliably associated with disrupted threat extinction. However, it is unclear whether IU would be related to disrupted extinction to other arousing stimuli that are not threatening (i.e., rewarding). We addressed this question by conducting a Pavlovian reward conditioning task with acquisition and extinction training phases (n=58). In the Pavlovian reward conditioning task, we recorded liking ratings, skin conductance response (SCR), and corrugator supercilii activity (i.e., brow muscle indicative or negative and positive affect) to learned reward (CS+) and neutral (CS-) cues. Typical patterns of reward acquisition and extinction training were observed for liking ratings. There was evidence for conditioning in SCR during the extinction training phase but not the acquisition training phase. However, no evidence of conditioning in either the acquisition or extinction training phase was observed for the corrugator supercilii. IU was not related to any measures during the acquisition or extinction training phases. Taken together, these results suggest that the current Pavlovian reward conditioning task was not sufficient for eliciting a reliable conditioned reward response, and therefore, further research with optimized reward conditioning designs are required to test whether IU-related deficits occur during the extinction of reward.

Emotional valence sensing using a wearable facial EMG device

Emotion sensing using physiological signals in real-life situations can be practically valuable. Previous studies have developed wearable devices that record autonomic nervous system activity, which reflects emotional arousal. However, no study determined whether emotional valence can be assessed using wearable devices. To this end, we developed a wearable device to record facial electromyography (EMG) from the corrugator supercilii (CS) and zygomatic major (ZM) muscles. To validate the device, in Experiment 1, we used a traditional wired device and our wearable device, to record participants’ facial EMG while they were viewing emotional films. Participants viewed the films again and continuously rated their recalled subjective valence during the first viewing. The facial EMG signals recorded using both wired and wearable devices showed that CS and ZM activities were, respectively, negatively and positively correlated with continuous valence ratings. In Experiment 2, we used the wearable device to record participants’ facial EMG while they were playing Wii Bowling games and assessed their cued-recall continuous valence ratings. CS and ZM activities were correlated negatively and positively, respectively, with continuous valence ratings. These data suggest the possibility that facial EMG signals recorded by a wearable device can be used to assess subjective emotional valence in future naturalistic studies.

Vocal Synchrony of Robots Boosts Positive Affective Empathy

Robots that can talk with humans play increasingly important roles in society. However, current conversation robots remain unskilled at eliciting empathic feelings in humans. To address this problem, we used a robot that speaks in a voice synchronized with human vocal prosody. We conducted an experiment in which human participants held positive conversations with the robot by reading scenarios under conditions with and without vocal synchronization. We assessed seven subjective responses related to affective empathy (e.g., emotional connection) and measured the physiological emotional responses using facial electromyography from the corrugator supercilii and zygomatic major muscles as well as the skin conductance level. The subjective ratings consistently revealed heightened empathic responses to the robot in the synchronization condition compared with that under the de-synchronizing condition. The physiological signals showed that more positive and stronger emotional arousal responses to the robot with synchronization. These findings suggest that robots that are able to vocally synchronize with humans can elicit empathic emotional responses.

Pictures of social interaction prompt a sustained increase of the smile expression and induce sociability

Viewing pictures of social interaction can facilitate approach behaviors. We conducted two studies to investigate if social interaction cues, empathy, and/or social touch modulate facial electromyographic (EMG) reactivity (as evidenced by the zygomaticus major and corrugator supercilii muscles) and mood states. We presented bonding pictures (depicting social interaction) and control pictures (without social interaction) while continuously recording zygomatic and corrugator EMG activities. In both studies, picture blocks were paired by valence and arousal. All participants were college students. In study 1, participants (n = 80, 47 women) read relevant priming texts immediately before viewing each block of 14 pictures. In study 2, participants did not read (n = 82, 63 women) priming texts before each block of 28 pictures. In study 1 and study 2, participants also completed mood states questionnaires to assess sociability and altruistic behavior. Empathy and social touch frequency were also assessed by self-reported questionnaires. In both studies, bonding pictures increased the zygomatic activity and the self-reported sociability feeling compared to control pictures. Only in study 2, bonding pictures decreased median corrugator activity compared to control pictures. We concluded that social interaction cues were efficient to increase sociability and prompt a sustained smile expression regardless of priming texts.

Selective denervation of the corrugator supercilii muscle for the treatment of idiopatic trigeminal neuralgia purely paroxysmal distributed in the supraorbital and suprathrochlear dermatomes

IntroductionIdiopatic trigeminal neuralgia purely paroxysmal (ITNp) distributed in the supraorbital and suprathrochlear dermatomes (SSd), refractory to conventional treatments have been linked to the hyperactivity of the corrugator supercilii muscle (CSM). In these patients, the inactivation of the CSM via botulinum toxin type A (BTA) injections has been proven to be safe and effective in reducing migraine burden. The main limitation of BTA is the need of repetitive injections and relative high costs. Based on the study of the motor innervation of the CSM, we describe here an alternative approach to improve these type of migraines, based on a minimally invasive denervation of the CSM.Materials and methodsMotor innervation and feasibility of selective CSM denervation was first studied on fresh frozen cadavers. Once the technique was safely established, 15 patients were enrolled. To be considered eligible, patients had to meet the following criteria: positive response to BTA treatment, migraine disability assessment score > 24, > 15 migraine days/month, no occipital/temporal trigger points and plausible reasons to discontinue BTA treatment. Pre- and post- operative migraine headache index (MHI) were compared, and complications were classified following the Clavien-Dindo classification (CDC).ResultsFifteen patients (9 females and 6 males) underwent the described surgical procedure. The mean age was 41 ± 10 years. Migraine headache episodes decreased from 24 ± 4 day/month to 2 ± 2 (p < 0.001) The MHI decreased from 208 ± 35 to 10 ± 11 (p < 0.001). One patient (7%) had a grade I complication according to the CDC. No patient needed a second operative procedure.ConclusionsOur findings suggest that the selective CSM denervation represents a safe and minimally invasive approach to improve ITNp distributed in the SSd associated with CSM hyperactivation.Trial registrationThe data collection was conducted as a retrospective quality assessment study and all procedures were performed in accordance with the ethical standards of the national research committee and the 1964 Helsinki Declaration and its later amendments.

Facial mimicry is independent of stimulus format: Evidence for facial mimicry of stick figures and photographs

The present research investigated facial mimicry of the basic emotions joy, anger, and sadness in response to stimuli in different formats. Specifically, in an electromyography study, 120 participants rated the expressions of joyful, angry, and sad faces presented as photographs or stick figures while facial muscle activity was measured. Using both frequentist and Bayesian approaches to hypothesis testing, we found strong support for a facial mimicry effect: Participants showed higher zygomaticus major and orbicularis oculi activity (smiling) towards joyful faces, while they showed higher corrugator supercilii activity (frowning) towards angry and sad faces. Although participants rated the stick figures as more abstract and less interesting stimuli, the mimicry effect was equally strong and independent of the format in which the faces were presented (photographs or stick figures). Additionally, participants showed enhanced emotion recognition for stick figures compared to photographs, which, however, was unrelated to mimicry. The findings suggest that facial mimicry occurs in response to stimuli varying in their abstractness and might be more robust to social-cognitive influences than previously assumed.

Electromyographic evidence of reduced emotion mimicry in individuals with a history of non-suicidal self-injury.

Engaging in facial emotion mimicry during social interactions encourages empathy and functions as a catalyst for interpersonal bonding. Decreased reflexive mirroring of facial expressions has been observed in individuals with different non-psychotic disorders, relative to healthy controls. Given reports of interpersonal relationship difficulties experienced by those who engage in non-suicidal self-injury (NSSI), it is of interest to explore facial emotion mimicry in individuals with a history of this behaviour (HNSSI). Among other things, this will enable us to better understand their emotion regulation and social interaction challenges. Surface facial electromyography (fEMG) was used to record the reflexive facial mimicry of 30 HNSSI and 30 controls while they passively observed a series of dynamic facial stimuli showing various facial expressions of emotion. Beginning with a neutral expression, the stimuli quickly morphed to one of 6 prototypic emotional expressions (anger, fear, surprise, disgust, happiness, or sadness). Mimicry was assessed by affixing surface electrodes to facial muscles known to exhibit a high degree of electrical activity in response to positive and negative emotions: the corrugator supercilii and the zygomaticus major. HNSSI participants, relative to controls, exhibited significantly less electrical activity in the corrugator muscle in response to viewing angry stimuli, and significantly less of an expected relaxation in muscle activity in response to viewing happy stimuli. Mirroring these results, greater endorsement of social influence as a motivator for engaging in NSSI was associated with less mimicry, and greater endorsement of emotion regulation as a motivator was associated with greater incongruent muscle response when viewing happy faces. These findings lend support to the theory that social interaction difficulties in HNSSI might be related to implicit violations of expected social rules exhibited through facial mimicry nonconformity.

Facial EMG Activity Is Associated with Hedonic Experiences but not Nutritional Values While Viewing Food Images.

The physiological correlates of hedonic/emotional experiences to visual food stimuli are of theoretical and practical interest. Previous psychophysiological studies have shown that facial electromyography (EMG) signals were related to subjective hedonic ratings in response to food images. However, because other data showed positive correlations between hedonic ratings and objective nutritional values of food, whether the facial EMG reactions to food images could reflect the hedonic evaluation or nutritional assessment of food remains unknown. To address this issue, we measured subjective hedonic ratings (liking, wanting, valence, and arousal) and physiological signals (facial EMG of the corrugator supercilii, zygomatic major, masseter, and suprahyoid muscles, skin potential responses, and heart rates) while participants observed food images that had objective nutritional information (caloric, carbohydrate, fat, and protein contents). The results revealed that zygomatic major EMG activity was positively correlated with ratings of liking, wanting, and valence, but not with any objective nutritional value. These data indicate that facial EMG signals in response to food images reflect subjective hedonic experiences, but not objective nutritional values, associated with the food item.

Climbing up or falling down: Narcissism predicts physiological sensitivity to social status in children and their parents.

Children's narcissism may be rooted in sensitivity to social status (i.e., prominence, respect, and influence in a social group), and this sensitivity might be shared with parents. Testing this idea, a randomized experiment examined how children with high narcissism levels and their parents respond to gains and losses of social status. On a simulated social media platform, children (N = 123, ages 8–13) competed with fictitious peers for status and were randomly assigned to gain or lose status. Unbeknownst to children, parents viewed the course of the task. Children's and parents' affective reactions during the task were measured with facial electromyography, which detects spontaneous facial muscle activity linked to positive affect (i.e., zygomaticus major activity, involved in smiling) and negative affect (i.e., corrugator supercilii activity, involved in frowning). Children with higher narcissism levels showed steeper increases in negative affect during status loss and steeper increases in both positive and negative affect during status gain. Their parents mirrored the steeper increase in positive affect during their child's status gain, but they did not mirror the increase in negative affect. These results suggest that children with high narcissism levels and their parents show intensified affective‐motivational responses to children's status‐relevant experiences. These responses may be transmitted from one generation to the other (e.g., genetically or through parent–child socialization).

Physiological correlates of subjective emotional valence and arousal dynamics while viewing films

An exploration of the physiological correlates of subjective emotional states has theoretical and practical significance. Previous studies have reported that subjective valence and arousal correspond to facial electromyography (EMG) and electrodermal activity (EDA), respectively, across stimuli. However, the reported results were inconsistent, no study investigated subjective–physiological concordance across time, and measures of arousal remain controversial. To investigate these issues, while healthy adults (n = 20) viewed emotional films, we assessed overall and continuous ratings of valence and arousal and recorded EMG from the corrugator supercilii and zygomatic major, EDA from the palms and forehead, and nose-tip temperature. The corrugator and zygomatic EMG were negatively and positively associated with valence ratings, respectively, across stimuli and time. EDA (both sites) and nose-tip temperature were positively and negatively associated with arousal ratings, respectively, across stimuli and time. It is concluded that subjective emotional valence and arousal dynamics have specific physiological correlates.

Assessment of threat and negativity bias in virtual reality

Negativity bias, i.e., tendency to respond strongly to negative stimuli, can be captured via behavioural and psychophysiological responses to potential threat. A virtual environment (VE) was created at room-scale wherein participants traversed a grid of ice blocks placed 200 m above the ground. Threat was manipulated by increasing the probability of encountering ice blocks that disintegrated and led to a virtual fall. Participants interacted with the ice blocks via sensors placed on their feet. Thirty-four people were recruited for the study, who were divided into High (HN) and Low (LN) Neuroticism groups. Movement data were recorded alongside skin conductance level and facial electromyography from the corrugator supercilii and zygomaticus major. Risk-averse behaviours, such as standing on ‘safe’ blocks and testing blocks prior to movement, increased when threat was highest. HN individuals exhibited more risk-averse behaviour than the LN group, especially in the presence of high threat. In addition, activation of the corrugator muscle was higher for HN individuals in the period following a movement to an ice block. These findings are discussed with respect to the use of room-scale VE as a protocol for emotion induction and measuring trait differences in negativity bias within VR.

Enhanced emotional and motor responses to live versus videotaped dynamic facial expressions

Facial expression is an integral aspect of non-verbal communication of affective information. Earlier psychological studies have reported that the presentation of prerecorded photographs or videos of emotional facial expressions automatically elicits divergent responses, such as emotions and facial mimicry. However, such highly controlled experimental procedures may lack the vividness of real-life social interactions. This study incorporated a live image relay system that delivered models’ real-time performance of positive (smiling) and negative (frowning) dynamic facial expressions or their prerecorded videos to participants. We measured subjective ratings of valence and arousal and facial electromyography (EMG) activity in the zygomaticus major and corrugator supercilii muscles. Subjective ratings showed that the live facial expressions were rated to elicit higher valence and more arousing than the corresponding videos for positive emotion conditions. Facial EMG data showed that compared with the video, live facial expressions more effectively elicited facial muscular activity congruent with the models’ positive facial expressions. The findings indicate that emotional facial expressions in live social interactions are more evocative of emotional reactions and facial mimicry than earlier experimental data have suggested.

Acute effects of alcohol on error-elicited negative affect during a cognitive control task.

Alcohol intoxication can dampen negative affective reactions to stressors. Recently, it has been proposed that these acute anxiolytic effects of alcohol may extend to dampening of negative affective reactions to error commission during cognitive control tasks. Nonetheless, empirical verification of this claim is lacking. Test the acute effect of alcohol on negative affective reactions to errors during an effort-demanding cognitive control task. Healthy, young adult social drinkers (N = 96 [49 women], 21-36years old) were randomly assigned to consume alcohol (0.80g/kg; n = 33 [15 female]), active placebo (0.04g/kg; n = 33 [18 women]), or a non-alcoholic control beverage (n = 30 [16 women]) before completing the Eriksen flanker task. Corrugator supercilii (Corr) activation, a psychophysiological index of negative affect, was tracked across the task. Two neurophysiological reactions to errors, the error-related negativity (ERN) and the error positivity (Pe), were also measured. Erroneous actions increased Corr activation in the control and (to a lesser extent) placebo groups, but not in the alcohol group. Error-induced Corr activation was coupled to ERN and Pe in the control, but not in the alcohol and placebo groups. Error-induced Corr activation was not coupled to post-error performance adjustments in any group. The ability of alcohol to dampen error-related negative affect was verified. It was also shown that placebo alone can disrupt coupling of affective and (neuro)cognitive reactions to errors. Although its behavioral relevance remains to be demonstrated, more attention should be paid to the role of affect in action monitoring and cognitive control processes.

Right Temporoparietal Junction Modulates In-Group Bias in Facial Emotional Mimicry: A tDCS Study.

The present study employs transcranial direct current stimulation (tDCS), a non-invasive brain stimulation technique, to explore the possible role of the right temporoparietal junction (rTPJ) in regulating in-group bias in facial emotional mimicry. Participants received either anodal or cathodal stimulation, or they were assigned to a sham condition. After that, they passively viewed a series of video clips depicting different emotions (happiness and anger) that were performed either by ethnic in-group or out-group models. The emotion-specific muscle activities, zygomatic major (ZM) and corrugator supercilii (CS) were recorded simultaneously as the index of facial emotional mimicry. The results first confirm the in-group bias in facial emotional mimicry in the sham condition, as shown in prior studies, though it only occurs in happy mimicry. Moreover, the in-group bias in facial emotional mimicry is modulated by the cortical excitability over the rTPJ, which may be attributed to the accompanied change of overlap of the mental representations of in-group and out-group. This study provides a close look at the neural underpinning of the modulation of facial emotional mimicry by group membership and highlights the role of rTPJ in on-line control of co-activated self and other representations in social cognition.

Smile (but only deliberately) though your heart is aching: Loneliness is associated with impaired spontaneous smile mimicry

ABSTRACT As social beings, humans harbor an evolved capacity for loneliness – perceived social isolation. Loneliness is associated with atypical affective and social processing, as well as physiological dysregulation. We investigated how loneliness influences spontaneous facial mimicry (SFM), an interpersonal response involved in social connection and emotional contagion. We presented participants with emotional stimuli, such as video clips of actors expressing anger, fear, sadness, or joy, and emotional IAPS images. We measured participants’ zygomaticus major (“smiling”) muscle and their corrugator supercilii (“frowning”) muscle with facial electromyography (fEMG). We also measured self-reported loneliness, depression, and extraversion levels. For socially connected individuals we found intact SFM, as reflected in greater fEMG activity of the zygomaticus and corrugator to positive and negative expressions, respectively. However, individuals reporting higher levels of loneliness lacked SFM for expressions of joy. Loneliness did not impair deliberate mimicry activity to the same expressions, or spontaneous reactions to positive, negative, or neutral IAPS images. Depression and extraversion did not predict any differences in fEMG responses. We suggest that impairments in spontaneous “smiling back” at another – a decreased interpersonal resonance – could contribute to negative social and emotional consequences of loneliness and may facilitate loneliness contagion.