The singer Bobby McFerrin, who visited Levitin’s lab and walked through several experiments, said in a video of that visit that “one of the things that I have found valuable to me in a performance, whether I’m performing or someone else is, is a certain element of naivete,” as if “as we’re performing we’re still discovering the music.”
In an interview, the singer Rosanne Cash said the experiments showed that beautiful compositions and technically skilled performers could do only so much. Emotion in music depends on human shading and imperfections, “bending notes in a certain way,” Cash said, “holding a note a little longer.”
She said she learned from her father, Johnny Cash, “that your style is a function of your limitations, more so than a function of your skills.”
“You’ve heard plenty of great, great singers that leave you cold,” she said. “They can do gymnastics, amazing things. If you have limitations as a singer, maybe you’re forced to find nuance in a way you don’t have to if you have a four-octave range.”
The brain processes musical nuance in many ways, it turns out. Edward Large, a music scientist at Florida Atlantic University, scanned the brains of people with and without experience playing music as they listened to two versions of a Chopin etude: one recorded by a pianist, the other stripped down to a literal version of what Chopin wrote, without human-induced variations in timing and dynamics.
During the original performance, brain areas linked to emotion activated much more than with the uninflected version, showing bursts of activity with each deviation in timing or volume.
So did the mirror neuron system, a set of brain regions previously shown to become engaged when a person watches someone doing an activity the observer knows how to do — dancers watching videos of dance, for example. But in Large’s study, mirror neuron regions flashed even in non-musicians.
Maybe those regions, which include some language areas, are “tapping into empathy,” he said, “as though you’re feeling an emotion that is being conveyed by a performer on stage,” and the brain is mirroring those emotions.
Regions involved in motor activity, everything from knitting to sprinting, also lighted up with changes in timing and volume.
Anders Friberg, a music scientist at KTH Royal Institute of Technology in Sweden, found that the speed patterns of people’s natural movements — moving a hand from one place to another on a desk or jogging and slowing to stop — match tempo changes in music that listeners rate as most pleasing.
“We got the best-sounding music from the velocity curve of natural human gestures, compared to other curves of tempos not found in nature,” Friberg said. “These were quite subtle differences, and listeners were clearly distinguishing between them. And these were not expert listeners.”
The Levitin project found that musicians were more sensitive to changes in volume and timing than non-musicians. That echoes research by Nina Kraus, a neurobiologist at Northwestern University in Illinois, which showed that musicians are better at hearing sound against background noise, and that their brains expend less energy detecting emotion in babies’ cries.
Separately, the Levitin team found that children with autism essentially rated each nocturne rendition equally emotional, finding the original no more emotionally expressive than the mechanical version. But in other research, the team found that children with autism could label music as happy, sad or scary, suggesting, Levitin said, that “their recognition of musical emotions may be intact without necessarily having those emotions evoked, and without them necessarily experiencing those emotions themselves.”