Explicit recognition of emotional facial expressions is shaped by expertise: evidence from professional actors

Inability to move one's face dampens facial expression perception

Humans rely heavily on facial expressions for social communication to convey their thoughts and emotions and to understand them in others. One prominent but controversial view is that humans learn to recognize the significance of facial expressions by mimicking the expressions of others. This view predicts that an inability to make facial expressions (e.g., facial paralysis) would result in reduced perceptual sensitivity to others' facial expressions. To test this hypothesis, we developed a diverse battery of sensitive emotion recognition tasks to characterize expression perception in individuals with Moebius Syndrome (MBS), a congenital neurological disorder that causes facial palsy. Using computer-based detection tasks we systematically assessed expression perception thresholds for static and dynamic face and body expressions. We found that while MBS individuals were able to perform challenging perceptual control tasks and body expression tasks, they were less efficient at extracting emotion from facial expressions, compared to matched controls. Exploratory analyses of fMRI data from a small group of MBS participants suggested potentially reduced engagement of the amygdala in MBS participants during expression processing relative to matched controls. Collectively, these results suggest a role for facial mimicry and consequent facial feedback and motor experience in the perception of others' facial expressions.

Reading and reacting to faces, the effect of facial mimicry in improving facial emotion recognition in individuals with antisocial behavior and psychopathic traits

Individuals with antisocial behavior and psychopathic traits are characterized by deficits in processing facial expressions, which results in poor social adaptation and dysfunctional interpersonal relationships. However, it is not clear how individuals with varying levels of these traits differ in this emotional impairment and if these deficits are due to correctly identifying or reacting appropriately to facial expressions. The aim of the study was to examine how individuals with these traits recognized and responded to affective facial expressions by using FaceReader software (which analyses footage of faces) across different experimental conditions (imitation, suppression, and control). Imitating facial expressions was introduced to examine whether it could direct participants’ attention to the facial cues and improve participants’ performance on the facial task. A total of 643 individuals from the community were pre-screened and a sample (N = 107; M age = 21.08, SD = 1.55), differentiated on levels of antisocial personality disorder (APD) symptoms and psychopathic (PSY) traits, who were selected based on extreme scores (high/low), were invited to participate in the study. Individuals with higher levels of APD symptoms and PSY traits (APD + PSY) expressed more anger than other groups, while those in the APD-only group expressed more sadness, compared to other groups. Overall, participants were compliant in following the instructions to imitate facial expressions. However, only the group with predominantly APD symptoms and the group with combined symptoms (APD + PSY) showed improvement in their accuracy ratings specifically when instructed to imitate facial expressions, compared to when no instructions were provided. The study offers a promising direction for targeting deficits in facial emotion recognition, suggesting that the deficits found in individuals with behavioral problems (with and without psychopathic traits) can be improved by asking them to imitate facial expressions.

Disorders of facial emotional expression and comprehension

One of the most important means of communicating emotions is by facial expressions. About 30-40 years ago, several studies examined patients with right and left hemisphere strokes for deficits in expressing and comprehending emotional facial expressions. The participants with right- or left-hemispheric strokes attempted to determine if two different actors were displaying the same or different emotions, to name the different emotions being displayed, and to select the face displaying an emotion named by the examiner. Investigators found that the right hemisphere-damaged group was impaired on all these emotional facial tests and that this deficit was not solely related to visuoperceptual processing defects. Further studies revealed that the patients who were impaired at recognizing emotional facial expressions and who had lost these visual representations of emotional faces often had damage to their right parietal lobe and their right somatosensory cortex. Injury to the cerebellum has been reported to impair emotional facial recognition, as have dementing diseases such as Alzheimer's disease and frontotemporal dementia, movement disorders such as Parkinson's disease and Huntington's disease, traumatic brain injuries, and temporal lobe epilepsy. Patients with right hemisphere injury are also more impaired than left-hemisphere-damaged patients when attempting to voluntarily produce facial emotional expressions and in their spontaneous expression of emotions in response to stimuli. This impairment does not appear to be induced by emotional conceptual deficits or an inability to experience emotions. Many of the disorders that cause impairments of comprehension of affective facial expressions also impair facial emotional expression. Treating the underlying disease may help patients with impairments of facial emotion recognition and expression, but unfortunately, there have not been many studies of rehabilitation.

Acting Surprised: Comparing Perceptions of Different Dynamic Deliberate Expressions

People are accurate at classifying emotions from facial expressions but much poorer at determining if such expressions are spontaneously felt or deliberately posed. We explored if the method used by senders to produce an expression influences the decoder’s ability to discriminate authenticity, drawing inspiration from two well-known acting techniques: the Stanislavski (internal) and Mimic method (external). We compared spontaneous surprise expressions in response to a jack-in-the-box (genuine condition), to posed displays of senders who either focused on their past affective state (internal condition) or the outward expression (external condition). Although decoders performed better than chance at discriminating the authenticity of all expressions, their accuracy was lower in classifying external surprise compared to internal surprise. Decoders also found it harder to discriminate external surprise from spontaneous surprise and were less confident in their decisions, perceiving these to be similarly intense but less genuine-looking. The findings suggest that senders are capable of voluntarily producing genuine-looking expressions of emotions with minimal effort, especially by mimicking a genuine expression. Implications for research on emotion recognition are discussed.

The psychology of professional and student actors: Creativity, personality, and motivation

As a profession, acting is marked by a high-level of economic and social riskiness concomitantly with the possibility for artistic satisfaction and/or public admiration. Current understanding of the psychological attributes that distinguish professional actors is incomplete. Here, we compare samples of professional actors (n = 104), undergraduate student actors (n = 100), and non-acting adults (n = 92) on 26 psychological dimensions and use machine-learning methods to classify participants based on these attributes. Nearly all of the attributes measured here displayed significant univariate mean differences across the three groups, with the strongest effect sizes being on Creative Activities, Openness, and Extraversion. A cross-validated Least Absolute Shrinkage and Selection Operator (LASSO) classification model was capable of identifying actors (either professional or student) from non-actors with a 92% accuracy and was able to sort professional from student actors with a 96% accuracy when age was included in the model, and a 68% accuracy with only psychological attributes included. In these LASSO models, actors in general were distinguished by high levels of Openness, Assertiveness, and Elaboration, but professional actors were specifically marked by high levels of Originality, Volatility, and Literary Activities.

Validating the Radboud faces database from a child's perspective

Facial expressions play a central role in diverse areas of psychology. However, facial stimuli are often only validated by adults, and there are no face databases validated by school-aged children. Validation by children is important because children still develop emotion recognition skills and may have different perceptions than adults. Therefore, in this study, we validated the adult Caucasian faces of the Radboud Faces Database (RaFD) in 8- to 12-year-old children (N = 652). Additionally, children rated valence, clarity, and model attractiveness. Emotion recognition rates were relatively high (72%; compared to 82% in the original validation by adults). Recognition accuracy was highest for happiness, below average for fear and disgust, and lowest for contempt. Children showed roughly the same emotion recognition pattern as adults, but were less accurate in distinguishing similar emotions. As expected, in general, 10- to 12-year-old children had a higher emotion recognition accuracy than 8- and 9-year-olds. Overall, girls slightly outperformed boys. More nuanced differences in these gender and age effects on recognition rates were visible per emotion. The current study provides researchers with recommendation on how to use the RaFD adult pictures in child studies. Researchers can select appropriate stimuli for their research using the online available validation data.

Incongruence Between Observers' and Observed Facial Muscle Activation Reduces Recognition of Emotional Facial Expressions From Video Stimuli

According to embodied cognition accounts, viewing others' facial emotion can elicit the respective emotion representation in observers which entails simulations of sensory, motor, and contextual experiences. In line with that, published research found viewing others' facial emotion to elicit automatic matched facial muscle activation, which was further found to facilitate emotion recognition. Perhaps making congruent facial muscle activity explicit produces an even greater recognition advantage. If there is conflicting sensory information, i.e., incongruent facial muscle activity, this might impede recognition. The effects of actively manipulating facial muscle activity on facial emotion recognition from videos were investigated across three experimental conditions: (a) explicit imitation of viewed facial emotional expressions (stimulus-congruent condition), (b) pen-holding with the lips (stimulus-incongruent condition), and (c) passive viewing (control condition). It was hypothesised that (1) experimental condition (a) and (b) result in greater facial muscle activity than (c), (2) experimental condition (a) increases emotion recognition accuracy from others' faces compared to (c), (3) experimental condition (b) lowers recognition accuracy for expressions with a salient facial feature in the lower, but not the upper face area, compared to (c). Participants (42 males, 42 females) underwent a facial emotion recognition experiment (ADFES-BIV) while electromyography (EMG) was recorded from five facial muscle sites. The experimental conditions' order was counter-balanced. Pen-holding caused stimulus-incongruent facial muscle activity for expressions with facial feature saliency in the lower face region, which reduced recognition of lower face region emotions. Explicit imitation caused stimulus-congruent facial muscle activity without modulating recognition. Methodological implications are discussed.

Post-earthquake Distress and Development of Emotional Expertise in Young Adults

After a natural disaster like an earthquake about 15% of the population experience a post-traumatic stress disorder (PTSD). However, even those without a diagnosis of PTSD can suffer from disorders of the affective sphere, including anxiety, depression and alteration of emotion recognition. The objective of this study was to investigate the neuropsychological and emotional profile of students living in the earthquake-affected areas of L'Aquila, Italy. A group of students living in L'Aquila at the time of the 2009 earthquake was recruited, and compared to a control group of students not living in any earthquake-affected areas. Participants were assessed by means of the Beck Depression Inventory (BDI) scale, the State-Trait Anxiety Inventory (STAI), the Insomnia Severity Index (ISI), the Intolerance of Uncertainty Scale Short Form, the Uncertainty Response Scale (URS), the Anxiety Sensitivity Index 3 (ASI-3), and the Eysenck Personality Questionnaire-Revised Short Form (EPQ-RS). Participants also took part in two behavioral experiments aimed at evaluating their ability to recognize facial expressions (by means of the Ekman and Friesen Pictures of Facial Affect) and to evaluate emotionally evocative scenes (by means of the International Affective Picture System (IAPS)). Results showed that students living in the earthquake-affected areas had a general increase of anxiety and anticipation of threats. Moreover, students living in the earthquake-affected areas showed a significantly higher overall accuracy in recognizing facial expressions as compared to controls. No significant differences between the two groups were detected in the evaluation of emotionally evocative scenes. The novel result lies in the greater accuracy of earthquake victims in recognizing facial expressions, despite the lack of differences from controls in evaluating affective evocative scenes. The trauma exposure may have increased vigilance for threats in earthquake victims, leading them to systematically pay attention to potential signs of approaching threats, such as emotional facial expressions, thus progressively developing particular "emotional expertise."

Transcranial Electrical Stimulation over Dorsolateral Prefrontal Cortex Modulates Processing of Social Cognitive and Affective Information

Recent neurofunctional studies suggested that lateral prefrontal cortex is a domain-general cognitive control area modulating computation of social information. Neuropsychological evidence reported dissociations between cognitive and affective components of social cognition. Here, we tested whether performance on social cognitive and affective tasks can be modulated by transcranial direct current stimulation (tDCS) over dorsolateral prefrontal cortex (DLPFC). To this aim, we compared the effects of tDCS on explicit recognition of emotional facial expressions (affective task), and on one cognitive task assessing the ability to adopt another person’s visual perspective. In a randomized, cross-over design, male and female healthy participants performed the two experimental tasks after bi-hemispheric tDCS (sham, left anodal/right cathodal, and right anodal/left cathodal) applied over DLPFC. Results showed that only in male participants explicit recognition of fearful facial expressions was significantly faster after anodal right/cathodal left stimulation with respect to anodal left/cathodal right and sham stimulations. In the visual perspective taking task, instead, anodal right/cathodal left stimulation negatively affected both male and female participants’ tendency to adopt another’s point of view. These findings demonstrated that concurrent facilitation of right and inhibition of left lateral prefrontal cortex can speed-up males’ responses to threatening faces whereas it interferes with the ability to adopt another’s viewpoint independently from gender. Thus, stimulation of cognitive control areas can lead to different effects on social cognitive skills depending on the affective vs. cognitive nature of the task, and on the gender-related differences in neural organization of emotion processing.