Executive
Functions
The Barkley/Bronowski theory of executive functions offers a unifying theory of ADHD (Barkley, 1999). Building on the Quay/Gray theory, Barkley agrees that ADHD arises from a deficiency of inhibition located in the pre-frontal cortex and goes on to delineate
four types of executive functions that are diminished by the lack of behavioral inhibition, contributing to the disruption of goal-directed motor behavior and self control.