They say that writing about music is like dancing about architecture. But why don’t we dance to paintings— or for that matter, buildings— anyway? The latest research hints at why.
According to a study published in the Proceedings of the National Academy of Sciences, music and dance share a parallel expression of emotion. The new research suggests that the two disciplines can express a mood together, with complementary methods of generating the dynamics of feeling.
The intuitive link between our feelings and movements is so strong that even the word “emotion” includes the word “motion.” And across cultures, the three-way connection between music, motion and feelings is maintained, such that being “moved” by either feelings or music is not just a concept of English-speaking people.
To better understand the roots of this deep connection, researchers at Dartmouth created a computer program that could produce either music or movement. Slider bars— similar to those on a mixing board— were created to control either the motion of an animated ball or the single notes of a piano, but not both at the same time.
Participants in the study included two very dissimilar groups: 50 college students in the U.S., and 87 villagers living in L’ak, a remote area of Cambodia, which is populated by the Kreung people. In this tribal group, music and dance mainly appear in ceremonies like weddings, funerals and animal sacrifices. The Kreung village is so isolated that members had never had any experiences with computers prior to the experiment.
In both the U.S. and Cambodian groups, participants were split into two groups for the experiment. All of them had to use the computer program to represent five different emotions: angry, happy, peaceful, sad and scared. But one group used the program in which the ball represented the emotion in movement, while the other used the program to play music to represent the feeling.
The program the scientists created allowed the participants to depict different aspects of the emotions. One slider bar, for example, controlled “rate,” which regulated how often notes or ball bounces occurred, better known to music lovers and dancers as beats per minute. Another handled “jitter” or the space between the notes or bounces. A third slider controlled the direction of either the music or the ball— whether the pitch or the ball moved up or down. The fourth handled the ratio of large to small movements: i.e., whether the pitch moved up quickly or slowly or the ball took large or small bounces. The final slider managed whether the music was consonant or dissonant or whether the ball moved smoothly or irregularly.
“The study is bold, challenging and interesting,” says Mark Changizi, an independent neuroscientist at the 2Ai Institute, who was not associated with the research but also studies the relationship between music and movement.
The authors write, “The critical question was whether subjects who used music to express an emotion set the slider bars to the same positions as subjects who expressed the same emotion with the moving ball.”
And to a large extent, that was what the researchers found. In the American group, each parameter was used in a similar way to create an image of an emotion, regardless of whether the output was music or motion. “These results strongly suggest the presence of a common structure,” the authors write.
Changizi’s research produced similar findings, although he used a different way of mapping music to movement, explored in his book, Harnessed. “I make the case that music has culturally evolved to sound like evocative human movement and behavior,” Changizi says, “By working out the ‘fingerprint’ of sounds people make when they move, I show that the same peculiar fingerprint is found in the structure of music.”
But is this unique to Western music? Other cultures may represent emotions differently in their music and their movements— or they may have parallel, but different expressions for emotion in music v. dance.
The study of U.S. and Cambodian participants suggests that different cultures may share parallel ways of expressing emotions in music and movement. Combining the data for music and movement together, the Kreung results for each emotion were more similar to the American results for the same emotion than they were to the other feelings, with one exception.
That exception was “angry.” The Kreung idea of “angry” music was closer to the American idea of “scared” music than it was to American rage music. But given the overlap in situations that elicit anger and fear, however, that trend is not entirely surprising.
Overall, the study authors conclude, “[T]he dynamic features of emotion expression are cross-culturally universal, at least for the five emotions tested here… these expressions have similar dynamic contours in both music and movement.”
So what does this tell us about what music and dance are “for”? Changizi notes that painting and sculpture can evoke emotion, but not the contagious type that tends to unify a group. “The visual arts may well evoke great feeling in us,” he says, describing how we may smile or even be moved to tears by a painting. “But [they don’t] make us really move, not like music can. Nearly all music may sound like someone moving about us, but dance music in particular probably sounds like someone engaging in a much more infectious behavior, one that in real life we might join.”
The study’s authors suggest that music may have evolutionary functions that aid survival, from “the soothing power of lullabies and the stimulating, synchronizing force of military marching rhythms” that can bind parents and children or entire nations together. The power of music may indeed be in its ability to move us, both literally and figuratively.
– Maia Szalavitz @maiasz is a neuroscience journalist for TIME.com and co-author of Born for Love: Why Empathy Is Essential — and Endangered.