Scientists have found that humans experience 27 distinct categories of emotion, thereby challenging the long-held assumption in psychology that humans have just six main categories, namely happiness sadness, anger, fear, disgust and surprise.
The team, from University of California, Berkeley, also created a multidimensional, interactive map that showed how each of the emotional states are connected rather than existing as “islands.”
“We don’t get finite clusters of emotions in the map because everything is interconnected. Emotional experiences are so much richer and more nuanced than previously thought,” explains lead author Alan Cowen.
For the study, 853 people viewed sequences of short video clips designed to evoke various feelings. Examples of themes covered in the clips were births, weddings, risky stunts, death, suffering, sexual acts and natural disasters.
The participants were divided into three groups that each completed a reporting task to describe their emotional responses after watching each clip.
The first group openly described their responses to each of 30 video clips, which Cowen says “reflected a rich and nuanced array of emotional states, ranging from nostalgia to feeling ‘grossed out.’” The second group ranked the videos in terms of how strongly they felt more than 30 different responses, with examples including excitement, interest, sympathy, surprise, calmness, nostalgia and confusion. Here, the team found that subjects converged on similar responses, with more than half reporting the same response to each video.
The third group were asked to rate their responses (on a scale of 1 to 9) to each of twelve clips, based on dichotomies such as dominance versus submissiveness and positive versus negative. Cowen and team found they could predict how the respondents would rate the videos based on the emotions participants had previously described.
As reported in Proceedings of the National Academy of Sciences, the researchers found that participants generally shared the same or similar responses to the videos and the data generated enabled them to identify 27 distinct emotional states.
Using innovative statistical models and visualization techniques, the team used the data to create a semantic map of human emotions, with each of the 27 emotional categories corresponding to a certain color.
Cowen says the aim is to shed light on the full palette of emotions that color our inner world:
Our hope is that our findings will help other scientists and engineers more precisely capture the emotional states that underlie moods, brain activity and expressive signals, leading to improved psychiatric treatments, an understanding of the brain basis of emotion and technology responsive to our emotional needs.”