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One of the regions, the anterior cingulate, is enlisted for most cognitive tasks, especially when the brain needs to decide between a surfeit of potentially conflicting responses. A neuroscience test called the Stroop task has become famous for riling up this region. Researchers show subjects the word “red,” but it’s written in the color blue. They’re then asked to either read the word aloud or say what color it is. “You feel your brain sort of freeze for a second,” said Berkowitz, an indication that the anterior cingulate is working hard. During improvisation, the musician has myriad, varied choices for what to play at any given moment, so it makes sense that this region would be fired up.
Another activated region, the dorsal premotor cortex, acts as a type of command center for crucial sensory input about where the body is and how it negotiates space. If the body has to move, what will be its goal and how fast should it go? Analyzing this input, the region issues a plan of action. When the musicians started to improvise, this region, already active during the playing of memorized melodies, ramped up significantly, possibly due to the musicians’ need to execute anything they could conceive of playing.
The third region Berkowitz identified—the inferior frontal gyrus/ventral premotor cortex—has long been known as an area key to our ability to understand and produce language. While more recent studies have linked it to music processing, Berkowitz and Ansari are the first to show that it plays a role in generating music as well. This would seem to strengthen the theory that music functions similar to language in the brain.
These results were published in 2008, but Berkowitz and Ansari released another study in early 2010 that took their investigation of improvisation one step further, pitting musicians against non-musicians. Keeping the setup and tasks the same, the scientists isolated an additional brain region that appears to be involved in improvisation. Called the right temporo-parietal junction, this region powers up when a new stimulus occurs in our environment, stealing our attention.
“For example, if you’re walking through the forest, it’s all trees, brown and green, and then suddenly something red pops out,” Berkowitz said. “This is the area that might say ‘Oh, something in my field of vision has changed and I need to draw attention to it.’ ” When the musicians were playing memorized melodies, this region was active, but as they began to improvise, the region shut down. The non-musicians showed no change in the region regardless of their task. Turning off this region, Berkowitz said, likely allows musicians to apply a steely focus to their improvisation—a feat, which according to Levin is critical. “If the brain gets distracted because the rhinestones on the pendant of the woman in the third row suddenly catch the light and for even a fraction of a second you lose focus, the music can lose its sense.”
Within weeks of Berkowitz’s first study coming out, a separate fMRI study on improvisation was published by Allen Braun, head of the Language Branch at the National Institutes of Health and Charles Limb, an otolaryngologist at Johns Hopkins Hospital. Where the Berkowitz/Ansari study tried to zero in on only those brain regions responsible for creativity during improvisation, the Limb/Braun study took a more holistic approach. Its goal was to glimpse every brain region enlisted in any aspect of improvisation.
Designing musical freedom into the study, which focused specifically on jazz, was challenging. Limb casts jazz and science, respectively, as the ultimate free spirit and control freak. “They’re just not really natural bedfellows,” he says.
Limb, a jazz saxophonist and self-described music addict whose lab resembles a recording studio due to its full-size piano keyboard and profusion of speakers, worked for two years with a California engineer to design a realistic, 35-key, plastic keyboard. He asked his subjects, all consummate jazz pianists, to perform two sets of musical tasks, while lying recumbent in the fMRI machine with the keyboard resting on their laps. The first set, intended to be simple, either had the pianists play a C major scale in sequence or allowed them to improvise, one note at a time within that scale. The second set was more complex. The subjects either played a short, pre-learned jazz tune composed by Limb or they improvised over a prerecorded four-piece band.
Results showed a veritable symphony of activated and deactivated brain regions during improvisation, which included the regions noted by Berkowitz and Ansari. The strangest activity, Limb said, occurred in the prefrontal cortex, where the scientists observed a surge in medial prefrontal activity, the “self-expressive, autobiographical brain region,” and, simultaneously, a broad deactivation in the lateral prefrontal regions, the area that governs self-consciousness and inhibition. In other words, in the improviser’s brain, the area that imposes self-restraint powers down, allowing the region that drives self-expression, which ramps up, to proceed virtually unchecked. “This notion of trying to tell your own musical story, without the constraints of caring how well it’s going as you’re saying it, was really pretty intriguing,” Limb said.
And so it happened for Robert Levin, seated at the piano, seized with panic, at the concert hall in Bremen. Memories of note patterns and chords embedded by thousands of practice hours, we may be certain, arose from his subconscious, flooding his brain. His lateral prefrontal regions said “This is it—time to tell your musical narrative,” while his medial prefrontal region reassured him, saying “Don’t worry about how it comes out.” His right temporo-parietal junction turned down the dial on any audience gasps, his anterior cingulate made a series of snap decisions, and his dorsal premotor cortex organized them into a motor missive, which it then sent out to his fingers. A split second later, Levin started to play, and before he knew it, he was home.
Amanda Rose Martinez is an award-winning science journalist and playwright. She writes about marine science, the environment and human nature.
Originally published December 14, 2010
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