Impulsivity: a review.

The most debated issues in the literature of impulsivity, starting with its most common definitions are reviewed. We examine the importance of serotonin and dopamine neurotransmitters and its relationship with the two widely known experimental confounds: timing and aggression. The various explanations of the causes of impulsivity, the ability to delay rewards and how the values of reinforcements fade with time are also reviewed. We follow with the role of working memory, attention and emotions, including self-control, and the concept of impulsivity as a lost chain between knowledge and action, ending with the idea that impulsive behavior is influenced by many different mechanisms. Finally, we present a brief description of some instruments used to measure impulsivity in both animal and human literature and its relationship with decision-making processes.