Via Jonah Lehrer:
The first study, led by Charles Limb of the NIH and Johns Hopkins University, examined the brain activity of jazz musicians as they played on a piano. The musicians began with pieces that required no imagination such as the C-major scale and a simple blues tune they’d memorized in advance. But then came the creativity condition: The musicians were told to improvise a new melody as they played alongside a recorded jazz quartet.
While the musicians riffed on the piano, giant magnets whirred overhead monitoring minor shifts in their brain activity. The researchers found that jazz improv relied on a carefully choreographed set of mental events, which allowed the musicians to discover their new melodies. Before a single note was played, the pianists exhibited a “deactivation” of the dorsolateral prefrontal cortex (DLPFC), a brain area associated with planned actions and self-control. In other words, they were inhibiting their inhibitions, which allowed the musicians to create without worrying about what they were creating.