Since the ’80s, lyrical magicians from Canibus to Chiddy Bang have intertwined their rhymes and rhythms to prove their

linguistic dexterity.

Researcher Ho Ming Chow runs test on rapper Mike Eagle, who was one of 12 participants in the study. Using an MRI machine, researchers found freestyling leads to increased activity in the part of the brain that relates to motivation and sustained behavior Courtesy NIDIC

This improvisational art form is known as freestyle rapping, and a group of researchers have used it to shed light on what happens in artists’ brains when they are experiencing these moments of

spontaneous creativity.

A study conducted by the National Institute on Deafness and Other Communication Disorders, published online in November’s issue of Scientific Reports, details how researchers scanned 12 rappers’ brains while they performed one rehearsed song and one improvised song. All subjects had at least five years of freestyle experience at the time and were observed performing eight bars of each song while inside an MRI machine.

“We think there are two phases to creative behavior,” said Siyuan Liu, lead researcher of the study. “First, [there is a] spontaneous phase, and second, a phase in which the material is revised and refined.”

Brain scans showed that when the rappers freestyled, there was increased activity in a region of the prefrontal cortex that relates to motivation and sustained behavior, while activity that relates to planning and self-monitoring decreased, said Allen Braun, study researcher and chief of the language section at the NIDIC, in

an email.

“This improvisatory state must be one in which highly motivated performance is conducted in the absence of self-censoring, in a state of free-flowing attention that may facilitate unplanned associations between words and generation of novel rhythmic patterns that are the hallmark of freestyling,”

Braun said.

Freestyling was also found to increase brain activity in areas relating to language production, emotion and motor skill functions, which suggests that this type of improvisation stimulates a network in the brain that links motivation, language, mood and action.

Liu said the researchers had previously studied neural activity in jazz musicians’ brains as they performed improvised melodies. The researchers are currently working on a follow-up study to analyze people’s brains as they

compose poetry.

Mike Waxx, founder of the hip-hop blog IllRoots.com, said freestyling requires talent.

“You need a good vocabulary, and it’s definitely a stream of consciousness you can’t force,” Waxx said. “A lot of rappers come up with their best lines off the top of their heads.”

Darnell Williams, a rapper based out of New York who has been rapping for more than seven years, said he has worked hard to reach a skilled level of freestyle lyricism.

During an exercise with a mentor, Williams was instructed to rap at least one bar about each word written on a board.

“When you’re freestyle rapping, it’s more so an emotion,” Williams said. “It’s whatever you’re feeling on the beat. It’s a certain mood you get from a beat and from there you just pull out ideas-—basically what rhymes and how it fits with

the mood.”