Sensorimotor simulation and emotion processing: Impairing facial action increases semantic retrieval demands

Abstract

Sensorimotor models suggest that understanding the emotional content of a face recruits a simulation process in which a viewer partially reproduces the facial expression in their own sensorimotor system. An important prediction of these models is that disrupting simulation should make emotion recognition more difficult. Here we used electroencephalogram (EEG) and facial electromyogram (EMG) to investigate how interfering with sensorimotor signals from the face influences the real-time processing of emotional faces. EEG and EMG were recorded as healthy adults viewed emotional faces and rated their valence. During control blocks, participants held a conjoined pair of chopsticks loosely between their lips. During interference blocks, participants held the chopsticks horizontally between their teeth and lips to generate motor noise on the lower part of the face. This noise was confirmed by EMG at the zygomaticus. Analysis of EEG indicated that faces expressing happiness or disgust-lower face expressions-elicited larger amplitude N400 when they were presented during the interference than the control blocks, suggesting interference led to greater semantic retrieval demands. The selective impact of facial motor interference on the brain response to lower face expressions supports sensorimotor models of emotion understanding.

The neuroethology of spontaneous mimicry and emotional contagion in human and non-human animals

“…More interestingly, the human literature emphasizes an additional function of such matching its facilitatory role in perception, experience, and understanding. As also discussed in section 5 of this article, preventing participants from engaging expression-relevant facial muscles can impair their ability to detect briefly presented or otherwise ambiguous facial expressions that involve that specific muscle (Bulnes et al, 2019;Davis et al, 2017;Neal & Chartrand, 2011;Niedenthal et al, 2001;Oberman et al, 2007;Stel and Knippenberg, 2008). Studies also show that inhibition of smiles leads to poorer differentiation between "true" and "false" smilesa process that relies on processing of subtle facial distinctions (Rychlowska et al, 2014).…”

The Mimicry Among Us: Intra- and Inter-Personal Mechanisms of Spontaneous Mimicry

“…However, some research provides evidence for the causal role of such spontaneous mimicry in emotion recognition. Preventing participants from engaging expression-relevant facial muscles, for example, sometimes impairs their ability to detect briefly presented, subtle, or ambiguous facial expressions that involve that specific muscle (Bulnes et al 2019;Davis et al 2017;Niedenthal et al 2001;Oberman et al 2007;Stel and Knippenberg 2008). In addition, studies show that inhibition of smiles results in poorer differentiation between "true" and "false" smiles-a process that relies on processing of subtle facial distinctions (Maringer et al 2011;Rychlowska et al 2014).…”

Out of Focus: Facial Feedback Manipulation Modulates Automatic Processing of Unattended Emotional Faces

“…Only a few studies so far have tested the influence of facial feedback manipulation on the processing of emotional faces on an electrophysiological level (Davis, Winkielman, & Coulson, 2017;Sel et al, 2015). In the study by Sel et al (2015), participants had to adopt a happy facial expression by biting on a pen or maintain a neutral facial expression by relaxing their facial muscles while they had to judge the intensity of facial expressions.…”

“…The concurrent EEG revealed that such facial feedback manipulation modulates the N170, a face-sensitive component of the visually evoked potential. In contrast, by biting on chopsticks, Davis et al (2017) attempted to disrupt the naturally produced feedback from the lower half of facial muscles and investigated the influence on the later semantic processing of facial expressions-with the result that this disruption increased the N400 (which is representative for the access to semantic information within memory) to happy and disgusted faces. Thus, the electrophysiological results of both studies indicate that facial mimicry manipulation can influence early perceptual as well as later semantic processing of facial emotional expressions.…”