The widespread action observation/execution matching system for facial expression processing

Abstract

Observing and understanding others' emotional facial expressions, possibly through motor synchronization, plays a primary role in face‐to‐face communication. To understand the underlying neural mechanisms, previous functional magnetic resonance imaging (fMRI) studies investigated brain regions that are involved in both the observation/execution of emotional facial expressions and found that the neocortical motor regions constituting the action observation/execution matching system or mirror neuron system were active. However, it remains unclear (1) whether other brain regions in the limbic, cerebellum, and brainstem regions could be also involved in the observation/execution matching system for processing facial expressions, and (2) if so, whether these regions could constitute a functional network. To investigate these issues, we performed fMRI while participants observed dynamic facial expressions of anger and happiness and while they executed facial muscle activity associated with angry and happy facial expressions. Conjunction analyses revealed that, in addition to neocortical regions (i.e., the right ventral premotor cortex and right supplementary motor area), bilateral amygdala, right basal ganglia, bilateral cerebellum, and right facial nerve nucleus were activated during both the observation/execution tasks. Group independent component analysis revealed that a functional network component involving the aforementioned regions were activated during both observation/execution tasks. The data suggest that the motor synchronization of emotional facial expressions involves a widespread observation/execution matching network encompassing the neocortex, limbic system, basal ganglia, cerebellum, and brainstem.

Inhibitory control towards angry stimuli in patients with binge eating disorder: a pilot study

“…One possible explanation of this might be that angry facial expressions impair the PFC by the activation of limbic regions as self-regulation capacities are limited in concordance with the self-regulation model of Heatherton and Wagner [ 17 ]. In line, a current fMRI study in healthy participants delivered evidence that angry facial stimuli activate a widespread neural observation/execution network including the amygdala besides frontal areas including the precentral gyrus, right pallidum, several regions in the cerebellum, and brainstem [ 28 ]. Another general population study using angry versus happy faces as the stop signal in the SST indicated that angry faces impair inhibitory control as they capture more attention compared to happy faces [ 29 ].…”

The Impact of the Perception of Primary Facial Emotions on Corticospinal Excitability

“…The ability to recognize emotional expressions is critical for survival and plays a pivotal role in successful social interactions. Converging evidence has suggested that the processing of emotional faces triggers the activation of widespread brain regions (for a review, see [ 1 ]), including motor areas such as the supplementary motor, premotor, and primary motor cortex [ 2 , 3 ]. The activation of the motor system during the perception of emotional faces has been interpreted as reflecting mechanisms of the preparation of adaptive motor responses, such as the fight/flight response [ 4 , 5 ], consistently with the long-held view that emotions prime the human body for action [ 6 , 7 , 8 ].…”