Probabilistic learning of emotion categories.

Abstract

Although the configurations of facial muscles that humans perceive vary continuously, we often represent emotions as categories. This suggests that, as in other domains of categorical perception such as speech and color perception, humans become attuned to features of emotion cues that map onto meaningful thresholds for these signals given their environments. However, little is known about the learning processes underlying the representation of these salient social signals. In Experiment 1 we test the role of statistical distributions of facial cues in the maintenance of an emotion category in both children (6–8 years old) and adults (18–22 years old). Children and adults learned the boundary between neutral and angry when provided with explicit feedback (supervised learning). However, after we exposed participants to different statistical distributions of facial cues, they rapidly shifted their category boundaries for each emotion during a testing phase. In Experiments 2 and 3, we replicated this finding and also tested the extent to which learners are able to track statistical distributions for multiple actors. Not only did participants form actor-specific categories, but the distributions of facial cues also influenced participants’ trait judgments about the actors. Taken together, these data are consistent with the view that the way humans construe emotion (in this case, anger) is not only flexible, but reflects complex learning about the distributions of the myriad cues individuals experience in their social environments.

Emotional Expressions Reconsidered: Challenges to Inferring Emotion From Human Facial Movements

“…It is possible that the frequency and type of facial input that people encounter influences their emotion categorizations. To test whether the statistical distribution of emotion input would influence how people construed boundaries between emotion categories, Plate, Wood, Woodard, and Pollak (2018) manipulated the frequency of this information to perceivers. Participants were asked to categorize facial morphs (from neutral to scowling) as being either "calm" or "upset."…”

“…Facial movements, like reflexive and voluntary motor movements (L. F. Barrett & Finlay, 2018), are strongly contextdependent. Recent evidence suggests that people's categories for emotions are flexible and responsive to the types and frequencies of facial movements to which they are exposed in their environments (Plate, Wood, Woodard, & Pollak, 2018).…”

Comment: A role of Language in Infant Emotion Concept Acquisition

“…Together, this evidence suggests that unsupervised learning also influences emotion concept development (see also Plate, Wood, Woodard, & Pollak, 2019). In both supervised and unsupervised learning, infants observe relations between expressive behaviors, eliciting events, and goal-based functions.…”

The Pacified Face: Early Embodiment Processes and the Use of Dummies

“…Even beyond these early developmental periods, people's emotion concepts are affected by the input from their environment (Levari et al, 2018). Plate et al (2018) recently showed that children and adults adjust their emotion categories based on the frequency of specific emotion expressions that they see. For example, children who saw more calm faces decreased their threshold for categorizing a face as angry.…”