Neuroscientist Charles Limb conducted a study several years ago out of Johns Hopkins University to measure the creative process in the brain. In his TED talk, he describes the experiment he designed that measured the brain activity of jazz pianists. He used an fMRI machine while they improvised on a MIDI keyboard. He monitored two parts of the brain: the medial prefrontal cortex (MPC) and the dorsolateral prefrontal cortex (DLPFC).
To define the parameters of the study: the medial prefrontal cortex is associated with self-expression (it’s like a mental narrator that keeps tabs on the story of your life) and the DLPFC is associated with impulse control (it edits your thoughts and words, and makes you think twice before yelling at your boss).
Limb’s findings show that the conscious mind has its strengths, but free flowing creative expression isn’t one of them. Much of creative expression is about relaxing or turning off the DLPFC and the self editing.
Sometimes alcohol does help turning off all the internal edits (when there aren’t skills at hand for turning it off at will). There is definite creative benefit to letting your inhibitions go.
This research confirms what trained improvisers already know: rational and deliberate thinking impair humor and creativity. It shows that people who try to be funny usually aren’t.
The most foundational rule of Improv is Say Yes. This bypasses the normal weighing of the pros and cons which kill comedy, fun and creativity.