'Stereotyping' emotions is getting in the way of artificial intelligence. Scientists say they've discovered a better way.

Understanding an emotion isn't as simple as noticing a smile-- but we still look to facial movements for everything from navigating everyday social interactions to the development of emotionally attuned artificial intelligence. According to a July 2019 study from researchers at Northeastern and the California Institute of Technology, facial expressions only reflect the surface of emotions: The culture, situation, and specific individual around a facial expression add nuance to the way a feeling is conveyed. For example, the researchers note that Olympic athletes who won medals only smiled when they knew they were being watched by an audience. While they were waiting behind the podium or facing away from people, they didn't smile (but were probably still happy). These results reinforce the idea that facial expressions aren't always reliable indicators of emotion.