“Jazz is absolutely defined by improvisation,” says Charles Limb, who is both a jazz saxophonist and a researcher at Johns Hopkins University and the National Institute on Deafness and Other Communication Disorders. “Once you get past the mechanics of the instrument, you’re not as concerned with the execution as the conception.” This moment of conception is what Limb and colleague Allen Braun captured in the brain in a recent experiment.
Limb and Braun used fMRI (functional magnetic resonance imaging) to map the brains of skilled jazz musicians as they improvised a tune. A special keyboard was designed for the experiment with no iron-containing metal parts, which would interfere with the powerful magnets in the fMRI machine. Each musician under study had to lie on his back with his head inside the scanner, playing the keyboard on his lap with one hand.
The study revealed the pattern of brain activity that occurs when composing music spontaneously. Interestingly, it is similar to that which occurs while dreaming. The results offer insight into how the brain enables jazz musicians to enter a sometimes trancelike creative state while performing.