# The challenge is to map the activity of every neuron in the brain by Rafael Yuste > "The challenge is to map the activity of every neuron in the brain." > **— Rafael Yuste**, *Brain Activity Map / BRAIN Initiative advocacy, wording candidate* Verification Status: Unverified — exact wording/source has not yet been independently confirmed against a primary source; source clue: Brain Activity Map / BRAIN Initiative advocacy, wording candidate.