Dr. Charles Limb has spent more than 10 years studying the brain activity of musicians as they improvise. In previous experiments, the auditory surgeon has put jazz piano players into functional magnetic resonance imaging (fMRI) machines to see how their brain activity changes during a jam session. Now he is studying whether the activity in rappers’ brains follows a similar pattern when they rhyme off the tops of their heads, according to a recent post on the TED Blog.
“There’s never been a scientific study of hip-hop ever,” Limb said in his TED Blog interview. “It’s not the kind of topic that I can glean much from other studies or the existing scientific literature. And I have to tell you, I’ve been having a ton of fun with this study, just experientially. When we were making our beats and our stimuli, trying to design the study, there’s no way to do this study without trying to rap yourself. It really transforms the lab!” (More on Time.com: Wait, ESP Is Real?)
So far, the doctor and his team at Johns Hopkins have worked with 12 professional freestyle rappers in the Baltimore area. Strapped into an fMRI machine, the hip-hop artists perform a memorized rap as a control test, and then a freestyle rap over a beat they’ve never heard before — improvising around verbal cues given at random times.
Limb said the work has proven especially fruitful because like him, his volunteers have been curious about what makes their brains tick when they’re creating lyrics. Limb also sees his work as contributing to good community relations: ”Given the image Johns Hopkins has as this conservative medical establishment in an inner city, but not of it, the idea that there’s a lab that wants to study hip-hop, I think there’s something appealing to the community,” he told the TED Blog.
The surgeon admitted that he wasn’t a big fan of hip-hop before the study, preferring to listen to classical music and jazz. Limb himself is a lifelong musician and said he always was interested in finding out how music makes our brains tick. (More on Time.com: Why We Conform to the Group: It Gets Your Brain High)
The results of his previous studies with jazz musicians revealed that when they improvised, activity in their brains’ inhibition centers slowed down. More specifically, according to a 2008 press release about the findings:
The scientists found that a region of the brain known as the dorsolateral prefrontal cortex, a broad portion of the front of the brain that extends to the sides, showed a slowdown in activity during improvisation. This area has been linked to planned actions and self-censoring, such as carefully deciding what words you might say at a job interview. Shutting down this area could lead to lowered inhibitions, Limb suggests.
The researchers also saw increased activity in the medial prefrontal cortex, which sits in the center of the brain’s frontal lobe. This area has been linked with self-expression and activities that convey individuality, such as telling a story about yourself.
“Jazz is often described as being an extremely individualistic art form. You can figure out which jazz musician is playing because one person’s improvisation sounds only like him or her,” says Limb. “What we think is happening is when you’re telling your own musical story, you’re shutting down impulses that might impede the flow of novel ideas.”
Having grown up around New York City, gone to medical school in New Haven and worked in Baltimore, the doctor told the TED Blog, he realized that rap had become to the current urban youth culture what jazz had been in the past. Given the similarities between the two styles of music, including the emphasis of rhythm, the use of improv and the fact that most musicians in both genres are not “classically” trained, hip-hop seemed like a natural genre to look at, Limb said. (More on Time.com: A Severe Migraine Could Give You a New Accent)
Limb’s hip-hop study is still ongoing so he has not yet revealed any data, but in a talk he delivered at TEDx Mid Atlantic in November 2010, he showed some of the brain scans, which showed that the verbal and — more surprisingly — visual areas of the musicians’ brains show activity during improvisation, even when the volunteers had their eyes closed.
So who’s on the wish list of rappers Limb would like to study? Eminem would be ideal, he said. During the TED interview, he even offered to fly the rapper to Baltimore to participate.