Most neuroscientists believe that the human brain does not reach full physical maturity until the calendar age of 25. Maturity is defined by a fully developed and functioning pre-frontal cortex. This area of the brain is located below the top of the head and behind the forehead. The pre-frontal cortex is responsible for executive function like long-term planning, execution of concepts, impulse control, rational judgment, and the ability to connect action with consequence.