Adrienne Wood

Fashioning the Face: Sensorimotor Simulation Contributes to Facial Expression Recognition

When we observe a facial expression of emotion, we often mimic it. This automatic mimicry reflects underlying sensorimotor simulation that supports accurate emotion recognition. Why this is so is becoming more obvious: emotions are patterns of expressive, behavioral, physiological, and subjective feeling responses. Activation of one component can therefore automatically activate other components. When people simulate a perceived facial expression, they partially activate the corresponding emotional state in themselves, which provides a basis for inferring the underlying emotion of the expresser. We integrate recent evidence in favor of a role for sensorimotor simulation in emotion recognition. We then connect this account to a domain-general understanding of how sensory information from multiple modalities is integrated to generate perceptual predictions in the brain.

Blocking Mimicry Makes True and False Smiles Look the Same

Recent research suggests that facial mimicry underlies accurate interpretation of subtle facial expressions. In three experiments, we manipulated mimicry and tested its role in judgments of the genuineness of true and false smiles. Experiment 1 used facial EMG to show that a new mouthguard technique for blocking mimicry modifies both the amount and the time course of facial reactions. In Experiments 2 and 3, participants rated true and false smiles either while wearing mouthguards or when allowed to freely mimic the smiles with or without additional distraction, namely holding a squeeze ball or wearing a finger-cuff heart rate monitor. Results showed that blocking mimicry compromised the decoding of true and false smiles such that they were judged as equally genuine. Together the experiments highlight the role of facial mimicry in judging subtle meanings of facial expressions.

Altering sensorimotor feedback disrupts visual discrimination of facial expressions

Looking at another person’s facial expression of emotion can trigger the same neural processes involved in producing the expression, and such responses play a functional role in emotion recognition. Disrupting individuals’ facial action, for example, interferes with verbal emotion recognition tasks. We tested the hypothesis that facial responses also play a functional role in the perceptual processing of emotional expressions. We altered the facial action of participants with a gel facemask while they performed a task that involved distinguishing target expressions from highly similar distractors. Relative to control participants, participants in the facemask condition demonstrated inferior perceptual discrimination of facial expressions, but not of nonface stimuli. The findings suggest that somatosensory/motor processes involving the face contribute to the visual perceptual—and not just conceptual—processing of facial expressions. More broadly, our study contributes to growing evidence for the fundamentally interactive nature of the perceptual inputs from different sensory modalities.

Towards a social functional account of laughter: Acoustic features convey reward, affiliation, and dominance

Recent work has identified the physical features of smiles that accomplish three tasks fundamental to human social living: rewarding behavior, establishing and managing affiliative bonds, and negotiating social status. The current work extends the social functional account to laughter. Participants (N = 762) rated the degree to which reward, affiliation, or dominance (between-subjects) was conveyed by 400 laughter samples acquired from a commercial sound effects website. Inclusion of a fourth rating dimension, spontaneity, allowed us to situate the current approach in the context of existing laughter research, which emphasizes the distinction between spontaneous and volitional laughter. We used 11 acoustic properties extracted from the laugh samples to predict participants’ ratings. Actor sex moderated, and sometimes even reversed, the relation between acoustics and participants’ judgments. Spontaneous laughter appears to serve the reward function in the current framework, as similar acoustic properties guided perceiver judgments of spontaneity and reward: reduced voicing and increased pitch, increased duration for female actors, and increased pitch slope, center of gravity, first formant, and noisiness for male actors. Affiliation ratings diverged from reward in their sex-dependent relationship to intensity and, for females, reduced pitch range and raised second formant. Dominance displayed the most distinct pattern of acoustic predictors, including increased pitch range, reduced second formant in females, and decreased pitch variability in males. We relate the current findings to existing findings on laughter and human and non-human vocalizations, concluding laughter can signal much more that felt or faked amusement.

Smiles as Multipurpose Social Signals

The human smile is highly variable in both its form and the social contexts in which it is displayed. A social-functional account identifies three distinct smile expressions defined in terms of their effects on the perceiver: reward smiles reinforce desired behavior; affiliation smiles invite and maintain social bonds; and dominance smiles manage hierarchical relationships. Mathematical modeling uncovers the appearance of the smiles, and both human and Bayesian classifiers validate these distinctions. New findings link laughter to reward, affiliation, and dominance, and research suggests that these functions of smiles are recognized across cultures. Taken together, this evidence suggests that the smile can be productively investigated according to how it assists the smiler in meeting the challenges and opportunities inherent in human social living.

Asymmetry of Facial Mimicry and Emotion Perception in Patients With Unilateral Facial Paralysis

IMPORTANCE The ability of patients with unilateral facial paralysis to recognize and appropriately judge facial expressions remains underexplored. OBJECTIVE To test the effects of unilateral facial paralysis on the recognition of and judgments about facial expressions of emotion and to evaluate the asymmetry of facial mimicry. DESIGN, SETTING, AND PARTICIPANTS Patients with left or right unilateral facial paralysis at a university facial plastic surgery unit completed 2 computer tasks involving video facial expression recognition. Side of facial paralysis was used as a between-participant factor. Facial function and symmetry were verified electronically with the eFACE facial function scale. EXPOSURES Across 2 tasks, short videos were shown on which facial expressions of happiness and anger unfolded earlier on one side of the face or morphed into each other. Patients indicated the moment or side of change between facial expressions and judged their authenticity. MAIN OUTCOMES AND MEASURES Type, time, and accuracy of responses on a keyboard were analyzed. RESULTS A total of 57 participants (36 women and 21 men) aged 20 to 76 years (mean age, 50.2 years) and with mild left or right unilateral facial paralysis were included in the study. Patients with right facial paralysis were faster (by about 150 milliseconds) and more accurate (mean number of errors, 1.9 vs 2.5) to detect expression onsets on the left side of the stimulus face, suggesting anatomical asymmetry of facial mimicry. Patients with left paralysis, however, showed more anomalous responses, which partly differed by emotion. CONCLUSIONS AND RELEVANCE The findings favor the hypothesis of an anatomical asymmetry of facial mimicry and suggest that patients with a left hemiparalysis could be more at risk of developing a cluster of disabilities and psychological conditions including emotion-recognition impairments. LEVEL OF EVIDENCE 3.

Feelings and contexts: socioecological influences on the nonverbal expression of emotion

Despite their relative universality, nonverbal displays of emotion are often sources of cross-cultural misunderstandings. The present article considers the relevance of historical and present socio-ecological contexts, such as heterogeneity of long-history migration, pathogen prevalence, and residential mobility for cross-cultural variation in emotional expression. We review recent evidence linking these constructs to psychological processes and discuss how the findings are relevant to the nonverbal communication of emotion. We hold that socioecological variables, because of their specificity and tractability, provide a promising framework for explaining why different cultures developed varying modes of emotional expression.

Why Do We Need Emotion Words in the First Place? Commentary on Lakoff (2015)

George Lakoff (2016) discusses how emotion metaphors reflect the discrete bodily states associated with each emotion. The analysis raises questions about the context for and frequency of use of emotion metaphors and, indeed, emotion labels (e.g., “angry”), per se. An assumption implicit to most theories of emotion is that emotion language is just another channel through which people express ongoing emotion states. Drawing from recent evidence that labeling ongoing emotions reduces their intensity, we propose that a primary function of emotion language is regulatory rather than expressive.

Language limits the experience of emotions Comment on "The quartet theory of human emotions: An integrative and neurofunctional model" by S. Koelsch et al.

Emotions are phylogenetically ancient and involve complex interactions of neural, behavioral, and physiological processes. A complete theory of emotions must incorporate, or at least be informed by, current knowledge from neurobiology and comparative psychology [1]. The Quartet Theory of Human Emotions by Koelsch and colleagues [2] is therefore a welcome step towards a more integrative affective science. A notable feature of the Quartet Theory is the clear proposed relationship between language and emotion systems, which diverges from current trends in affective science. Many theories of emotion that specify a role for language in affective processes suggest that language and concepts either create, differentiate, facilitate awareness of, and/or express emotional states [e.g., 3–5]. These theories are based in part on the assumption that emotion words can accurately and precisely encapsulate internal feeling states. Some even suggest that verbally categorizing diffuse affective states coheres them into what we then experience as discrete and differentiated emotions [4,5]. In contrast, the Quartet Theory suggests that linguistic categorization of emotion percepts—the summed “felt” components of affect—is neither an automatic nor essential step in an emotion experience. Language facilitates regulation (e.g., through reappraisal), and sometimes, expression of emotions. However, the authors argue that translating a pre-verbal emotion percept into language results in the loss of important diagnostic information [6], which is problematic (as the philosopher Ludwig Wittgenstein argued) because speakers cannot be confident that their understanding of an emotion word is the same as another person’s.1 Thus it is unlikely that language and concepts play a fundamental role in the emotion itself because categorizing an emotion percept reconfigures it. We agree that emotion percepts are pre-verbal internal states and emotion labels therefore do a poor job of communicating them. We also agree that language is a powerful tool for conscious emotion regulation. We would like to push the argument even further and suggest that the simple act of labeling an ongoing emotion percept automatically

Heterogeneity of long-history migration predicts smiling, laughter and positive emotion across the globe and within the United States

Recent findings demonstrate that heterogeneity of long-history migration predicts present-day emotion behaviors and norms. Residents of countries characterized by high ancestral diversity display emotion expressions that are easier to decode by observers, endorse norms of higher emotion expressivity, and smile more in response to certain stimuli than residents of countries that lack ancestral diversity. We build on the extant findings and investigate historical heterogeneity as a predictor of daily smiling, laughter, and positive emotion across the world’s countries and the states of the United States. Study 1 finds that historical heterogeneity is positively associated with self-reports of smiling, laughter, and positive emotions in the Gallup World Poll when controlling for GDP and present-day population diversity. Study 2 extends the findings to effects of long-history migration within the United States. We estimated the average percentage of foreign-born citizens in each state between 1850 and 2010 based on US Census information as an indicator of historical heterogeneity. Consistent with the world findings of Study 1, historical heterogeneity predicted smiling, laughter, and positive, but not negative, emotion. The relationships remained significant when controlling for per capita income and present-day population diversity of each state. Together, the findings further demonstrate the important role of long-history migration in shaping emotion cultures of countries and states, which persist beyond the original socio-ecological conditions, and open promising avenues for cross-cultural research.