Corrugator Supercilii Activity Research Articles

Voluntary facial activations regulate physiological arousal and subjective experiences during virtual social stimulation

Exposure to distressing computer-generated stimuli and feedback of physiological changes during exposure have been effective in the treatment of anxiety disorders (e.g., social phobia). Here we studied voluntary facial activations as a method for regulating more spontaneous physiological changes during virtual social stimulation. Twenty-four participants with a low or high level of social anxiety activated either the corrugator supercilii (used in frowning) or the zygomaticus major (used in smiling) facial muscle to keep a female or a male computer character walking towards them. The more socially anxious participants had a higher level of skin conductance throughout the trials as compared to less anxious participants. Within both groups, short-term skin conductance responses were enhanced both during and after facial activations; and corrugator supercilii activations facilitated longer term electrodermal relaxation. Zygomaticus major activations had opposite effects on subjective emotional ratings of the less and the more socially anxious. In sum, voluntary facial activations were effective in regulating emotional arousal during virtual social exposure. Corrugator supercilii activation was found an especially promising method for facilitating autonomic relaxation.

Preattentive processing of feared stimuli in blood–injection–injury fearful subjects

This research aimed to study the defence responses of blood–injection–injury (BII) fearful subjects elicited by the preattentive processing of their feared objects and by an abrupt acoustic stimulus. We selected 21 BII fearful subjects and 25 non-fearful controls from an initial sample of 128 women, according to their scores on the Fear Survey Scale (damage subscale) and the Mutilation Questionnaire. Subjects were exposed to a burst of white noise to promote a defence response, and to 48 pictures, depicting mutilations, as well as other affective contents, displayed through a backward masking procedure. Heart rate (HR), skin conductance response (SCR) and corrugator supercilii activity were continuously recorded throughout the task. Both groups showed similar SCRs, EMG activity and cardiac defence responses to the acoustic stimulus, though fearful subjects showed greater initial HR deceleration than controls. While BII fearful subjects displayed the usual defence response when exposed to a non-feared threatening stimulus, the preattentive processing of the pictures did not reveal autonomic differences between fearful subjects and controls. Mutilation pictures, however, evoked the greatest EMG activity, but only in the fearful group. These data further extend previous research on conscious perception of blood-related stimuli in BII fearful subjects, by showing a failure to recruit autonomic defence responses when blood-related pictures appear outside of conscious awareness.

Facial mimicry and the mirror neuron system: simultaneous acquisition of facial electromyography and functional magnetic resonance imaging

Numerous studies have shown that humans automatically react with congruent facial reactions, i.e., facial mimicry, when seeing a vis-á-vis' facial expressions. The current experiment is the first investigating the neuronal structures responsible for differences in the occurrence of such facial mimicry reactions by simultaneously measuring BOLD and facial EMG in an MRI scanner. Therefore, 20 female students viewed emotional facial expressions (happy, sad, and angry) of male and female avatar characters. During picture presentation, the BOLD signal as well as M. zygomaticus major and M. corrugator supercilii activity were recorded simultaneously. Results show prototypical patterns of facial mimicry after correction for MR-related artifacts: enhanced M. zygomaticus major activity in response to happy and enhanced M. corrugator supercilii activity in response to sad and angry expressions. Regression analyses show that these congruent facial reactions correlate significantly with activations in the IFG, SMA, and cerebellum. Stronger zygomaticus reactions to happy faces were further associated to increased activities in the caudate, MTG, and PCC. Corrugator reactions to angry expressions were further correlated with the hippocampus, insula, and STS. Results are discussed in relation to core and extended models of the mirror neuron system (MNS).

Faces differing in attractiveness elicit corresponding affective responses

We examined whether faces differing in attractiveness elicit positive and negative affect in 7- to 10-year-old children (N=66) and adults (N=73). Facial electromyography measured affective response. Less attractive faces evoked significantly more levator labii superioris responses in adults and children. Attractiveness was negatively correlated with corrugator supercilii activity in adults, but not significantly in children. These results suggest that less attractive faces evoke greater disgust and negative affect than more attractive faces. Perceivers' affective reactions to attractive faces may play an important role in attractiveness preferences and attractiveness stereotypes.

Modulation of facial reactions to avatar emotional faces by nonconscious competition priming

To investigate whether subliminally priming for competition influences facial reactions to facial emotional displays, 49 participants were either subliminally competition primed or neutrally primed. Thereafter, they viewed computer generated avatar faces with happy, neutral, and sad expressions while Corrugator supercilii and Zygomaticus major reactions were recorded. Results revealed facial mimicry to happy and sad faces in the neutrally primed group but not the competition primed group. Furthermore, subliminal competition priming enhanced Corrugator supercilii activity after an initial relaxation while viewing happy faces. An impression formation task revealed counter empathic effects confirming successful competition priming. Overall, results indicate that nonconscious processes influence a presumably nonconscious behavior.

Attentional bias is associated with incentive-related physiological and subjective measures.

Drug cue reactivity is theoretically and clinically important. The modified Stroop task has been widely used to assess attention capture by drug cues (attentional bias). Attentional bias to drug cues is assumed to reflect the incentive value of those cues, but this has not been directly tested. The authors examined whether the smoking Stroop effect was associated with facial electromyography (EMG) assessed in real time. Heart-rate (HR) and skin conductance (SC) responses were also assessed. Smokers (n = 79) attended up to four experimental sessions. Presession Abstinence state and within-session Smoking were manipulated across sessions. Over all assessments, participants exhibited a robust smoking Stroop effect. Using Generalized Estimating Equations (GEE) analyses, the smoking Stroop effect was positively associated with zygomaticus major activity but not with corrugator supercilii activity, HR, or SC. The smoking Stroop effect was also positively associated with self-reported positive outcome expectancies from smoking and with craving. In sum, attentional bias was more strongly associated with appetitive responses (zygomaticus major activity, positive outcome expectancies) than with withdrawal responses (e.g., corrugator supercilii activity) or measures of physiological arousal (e.g., HR, SC).

Electromyographic responses to static and dynamic avatar emotional facial expressions

Facial muscular reactions to avatars' static (neutral, happy, angry) and dynamic (morphs developing from neutral to happy or angry) facial expressions, presented for 1 s each, were investigated in 48 participants. Dynamic expressions led to better recognition rates and higher intensity and realism ratings. Angry expressions were rated as more intense than happy expressions. EMG recordings indicated emotion-specific reactions to happy avatars as reflected in increased M. zygomaticus major and decreased M. corrugator supercilii tension, with stronger reactions to dynamic as compared to static expressions. Although rated as more intense, angry expressions elicited no significant M. corrugator supercilii activation. We conclude that facial reactions to angry and to happy facial expressions hold different functions in social interactions. Further research should vary dynamics in different ways and also include additional emotional expressions.

Manipulating affective state using extended picture presentations

Separate, extended series of positive, negative, and neutral pictures were presented to 24 (12 men, 12 women) undergraduates. Each series was presented on a different day, with full counterbalancing of presentation orders. Affective state was measured using (a) orbicularis oculi activity in response to acoustic startle probes during picture presentation, (b) corrugator supercilii activity between and during picture presentation, and (c) changes in self-reports of positive and negative affect. Participants exhibited larger eyeblink reflex magnitudes when viewing negative than when viewing positive pictures. Corrugator activity was also greater during the negative than during the positive picture set, during both picture presentation and the period between pictures. Self-reports of negative affect increased in response to the negative picture set, and self-reports of positive affect were greatest following the positive picture set. These findings suggest that extended picture presentation is an effective method of manipulating affective state and further highlight the utility of startle probe and facial electromyographic measures in providing on-line readouts of affective state.

Different facial EMG-reactions of extraverts and introverts to pictures with positive, negative and neutral valence

During the presentation of slides with positive, negative and neutral emotional valence, EMG-reactions of three different facial muscles were recorded. The experimental group was divided into 20 extraverted and 21 introverted subjects, using the German version of the EPQ. Similar to comparable studies it turned out that the activity of the m. zygomaticus major increased presenting pictures with positive valence, whereas the m. corrugator supercilii activity increased during the presentation of pictures with negative valence. However, introverts and extraverts did not differ in their average activity of the m. corrugator and the m. zygomaticus major. Introverts showed a stronger m. depressor anguli oris reaction than extraverts. Since this muscle is used to draw down the cheeks, thereby acting against smiling, normally accompanied by an elevation of the cheeks, we hypothesize that introverts actively inhibit their facial expression of positive emotions.