Facial EMG – Investigating the Interplay of Facial Muscles and Emotions

This chapter provides information about facial electromyography (EMG) as a method of investigating emotions and affect, including examples of application and methods for analysis. This chapter begins with a short introduction to emotion theory followed by an operationalisation of facial emotional expressions as an underlying requirement for their study using facial EMG. This chapter ends by providing practical information on the use of facial EMG

Diminished sensitivity and specificity at recognising facial emotional expressions of varying intensity underlie emotion-specific recognition deficits in autism spectrum disorders

Background A plethora of research on facial emotion recognition in autism spectrum disorders (ASD) exists and reported deficits in ASD compared to controls, particularly for negative basic emotions. However, these studies have largely used static high intensity stimuli. The current study investigated facial emotion recognition across three levels of expression intensity from videos, looking at accuracy rates to investigate impairments in facial emotion recognition and error patterns (’confusions’) to explore potential underlying factors. Method Twelve individuals with ASD (9 M/3F; M(age) = 17.3) and 12 matched controls (9 M/3F; M(age) = 16.9) completed a facial emotion recognition task including 9 emotion categories (anger, disgust, fear, sadness, surprise, happiness, contempt, embarrassment, pride) and neutral, each expressed by 12 encoders at low, intermediate, and high intensity. Results A facial emotion recognition deficit was found overall for the ASD group compared to controls, as well as deficits in recognising individual negative emotions at varying expression intensities. Compared to controls, the ASD group showed significantly more, albeit typical, confusions between emotion categories (at high intensity), and significantly more confusions of emotions as ‘neutral’ (at low intensity). Conclusions The facial emotion recognition deficits identified in ASD, particularly for negative emotions, are in line with previous studies using other types of stimuli. Error analysis showed that individuals with ASD had difficulties detecting emotional information in the face (sensitivity) at low intensity, and correctly identifying emotional information (specificity) at high intensity. These results suggest different underlying mechanisms for the facial emotion recognition deficits at low vs high expression intensity

Playing Pokemon Go: increased life satisfaction through more (positive) social interactions

Pokemon Go (PoGo) is a social mobile game requiring both physical activity and social interaction, and previous research has reported positive effects of PoGo on physical health. However, little research has been conducted on the effects of PoGo on social functioning and life satisfaction, which are important factors for good mental health. The current study investigated the effects of PoGo on life satisfaction and social functioning in participants with and without self-reported diagnoses of mental disorders. Participants were 434 current PoGo players aged 18–69 of diverse genders and nationalities, with a subsample (N = 138) self-reporting diagnoses of various mental disorders with impairments in social functioning. Participants provided retrospective and current self-report measures about their PoGo use, life satisfaction, social functioning (sociality and social ability) and clinical symptom severity. Results showed higher self-reported social functioning and life satisfaction since playing PoGo compared to the time period before playing, which involved a shift from negative to positive ratings. The increases in self-reported life satisfaction and sociality (but not social ability) were more pronounced for the clinical compared to the non-clinical subsample. Results also showed the effect of the social ability change on the life satisfaction change was mediated by the sociality change and moderated by the number of daily in-person player interactions (including strangers). The findings here, using subjective judgements, show that PoGo motivates social interactions and increases life satisfaction, demonstrating that social mobile gaming provides an easy to implement tool to subjectively improve social functioning. This has important implications for populations with social difficulties and reduced social motivation

It does not need two: assessing physiological linkage from videos across the valence dimension

The phenomenon of physiological linkage describes similar fluctuations of two individuals' physiology, for example, the cardiac inter- beat interval (IBI). Physiological linkage is a well- documented occurrence in research settings of interacting dyads but the literature on non- interacting dyads, that is, someone watching a video of another person, is sparse. The current study investigated whether physiological linkage, based on IBI, occurs from watching videos where strangers report about personal (neutral, positive, negative non- traumatic, and negative traumatic) experiences. Videos were produced with six individuals and then presented to observers (N=26). Time- frequency- domain cross- wavelet analyses supplemented by threshold-free cluster enhancement (TFCE; to account for multiple testing) showed significant physiological linkage between the IBI of observers and persons in the videos for 16 out of the 21 tested videos. Although significant physiological linkage also emerged for neutral videos and positive, negative valence videos led to such associations more reliably. This study shows that physiological linkage can be investigated in highly controlled conditions based on video stimuli paving the path for experimental manipulation in future research. Furthermore, due to the provision of information on time and frequency, the use of cross- wavelet analysis is encouraged to learn more about factors modulating physiological linkage. The current study presents the next step toward identifying psychophysiological causal and modulating factors of physiological linkage

Evaluations of affective stimuli modulated by another person's presence and affiliative touch

Affiliative touch carries affective meaning and affects the receiver. Although research demonstrates that receiving touch modulates the neural processing of emotions, its effects on evaluations of affective stimuli remain unexplored. The current research examined the effects of affiliative touch on the evaluation of affective images across 3 studies and aimed to disentangle the effect of another person’s mere presence from the addition of affiliative touch. Participants thus underwent experimental conditions of social manipulation (presence, alone) and touch manipulations (receiving, self-providing, providing to experimenter) while viewing affective images (negative, neutral, and positive valence) and evaluated their valence. Study 1 included hand-squeezing (N = 39), and Study 2 included forearm-stroking (N = 40) in a within-subjects design. Study 3 included hand-squeezing (N = 109) in a between-subjects design. Across both studies, the results suggested that the receiving condition decreased the negativity of negative images, and the providing condition reduced the positivity of positive images. Furthermore, the other presence condition increased the positivity of positive images compared with the alone condition in Study 1 and to the receiving condition in Study 2. Hand-squeezing and forearm-stroking had differential effects on affective image evaluations depending on the image valence and who provided the touch. Overall, receiving touch seems to attenuate negative evaluations in negative contexts and the presence of others amplifies positive evaluations in positive situations. Discussion highlights the importance of affiliative touch within social interactions

Modulation of facial muscle responses by another person’s presence and affiliative touch during affective image viewing

Stimulating CT-afferents by forearm caresses produces the subjective experience of pleasantness in the receiver and modulates subjective evaluations of viewed affective images. Receiving touch from another person includes the social element of another person’s presence, which has been found to influence affective image evaluations without involving touch. The current study investigated whether these modulations translate to facial muscle responses associated with positive and negative affect across touch-involving and mere presence conditions. Female participants (N = 40, M(age) = 22.4, SD = 5.3) watched affective images (neutral, positive, negative) while facial electromyography was recorded (sites: zygomaticus, corrugator). Results from ANOVAs showed that providing touch to another person or oneself modulated zygomaticus site responses when viewing positive images. Providing CT-afferent stimulating touch (i.e., forearm caresses) to another person or oneself dampened the positive affective facial muscle response to positive affective images. Providing touch to another person generally increased corrugator facial muscle activity related to negative affect. Receiving touch did not modulate affective facial muscle responses during the viewing of affective images but may have effects on later cognitive processes. Together, previously reported social and touch modulations of subjective evaluations of affective images do not translate to facial muscle responses during affective image viewing, which were differentially modulated

Social and Affective Neuroscience of Embodiment

Embodiment has been discussed in the context of social, affective, and cognitive psychology, and also in the investigations of neuroscience in order to understand the relationship between biological mechanisms, body and cognitive, and social and affective processes. New theoretical models have been presented by researchers considering not only the sensory–motor interaction and the environment but also biological mechanisms regulating homeostasis and neural processes (Tsakiris M, Q J Exp Psychol 70(4):597–609, 2017). Historically, the body and the mind were comprehended as separate entities. The body was considered to function as a machine, responsible for providing sensory information to the mind and executing its commands. The mind, however, would process information in an isolated way, similar to a computer (Pecher D, Zwaan RA, Grounding cognition: the role of perception and action in memory, language, and thinking. Cambridge University Press, 2005). This mind and body perspective (Marmeleira J, Duarte Santos G, Percept Motor Skills 126, 2019; Marshall PJ, Child Dev Perspect 10(4):245–250, 2016), for many years, was the basis for studies in social and cognitive areas, in neuroscience, and clinical psychology

Implicit responses in the judgment of attractiveness in faces with differing levels of makeup

Makeup is a form of body art which has been used for over 7000 years and is present in the great majority of human cultures, often used to enhance facial attractiveness and to accentuate features that represent femininity. This study examined how cumulative levels of facial makeup influenced approach and avoidance tendencies and on facial muscle responses associated with emotional response obtained through facial electromyography (EMG) in a passive viewing task. Experiment 1 employed the joystick variant of the approach-avoidance task, where 30 subjects categorised female faces by visual orientation (portrait/landscape) in 7 cumulatively-added makeup levels. In Experiment 2, facial EMG was recorded from 40 subjects in the passive viewing of the same images. The present study shows that makeup application modulates implicit responses and reveals two distinct implicit preferences, behavioural and affective, with a male behavioural preference for heavy eye cosmetics, a female behavioural preference for light makeup, and an overall affective preference in both men and women for makeup accentuating visual contrast in the eye and mouth regions. These results are consistent with the conception that perceptual cues underlying cosmetic enhancement are key determinants in aesthetic facial preferences

Development and validation of verbal emotion vignettes in Portuguese, English, and German

Everyday human social interaction involves sharing experiences verbally and these experiences often include emotional content. Providing this context generally leads to the experience of emotions in the conversation partner. However, most emotion elicitation stimulus sets are based on images or film-sequences providing visual and/or auditory emotion cues. To assimilate what occurs within social interactions, the current study aimed at creating and validating verbal emotion vignettes as stimulus set to elicit emotions (anger, disgust, fear, sadness, happiness, gratitude, guilt, and neutral). Participants had to mentally immerse themselves in 40 vignettes and state which emotion they experienced next to the intensity of this emotion. The vignettes were validated on a large sample of native Portuguese-speakers (N = 229), but also on native English-speaking (N = 59), and native German-speaking (N = 50) samples to maximise applicability of the vignettes. Hierarchical cluster analyses showed that the vignettes mapped clearly on their target emotion categories in all three languages. The final stimulus sets each include 4 vignettes per emotion category plus 1 additional vignette per emotion category which can be used for task familiarisation procedures within research. The high agreement rates on the experienced emotion in combination with the medium to large intensity ratings in all three languages suggest that the stimulus sets are suitable for application in emotion research (e.g., emotion recognition or emotion elicitation)