Attention deficit hyperactivity disorder (ADHD) is a neurological disorder which is common in the childhood and can be caused by exogenous and endogenous factors, that are responsible for cerebral disorder. This disorder presents a functional alteration of the motor, perceptive, cognition systems and conduct disorders compromising the learning of children with an adequate intellectual potential. The authors study the action of stimulants and antidepressive drugs in the ADHD, using as measure of efficacy the motor persistence tests.