Impulsive behaviors are not necessarily pathological and likely reflect the individual’s desire/motivation to obtain high salience outcomes like social dominance,3 high-energy nutrients,4 sex5–7 or other rewards. They are, in that sense, adaptive behaviors that may well have been subject to selection forces that encourage quick exploratory or risk-taking actions, in favor of slower, more deliberative and risk-averse choices. The advantageous nature of a certain degree of impulsive tendencies is likely reflected in the fact that alleles associated with higher propensity for impulsivity are highly conserved in mammals; for example, the dopamine D4 receptor exon 3 variable number tandem repeat polymorphism often linked with impulsive behaviors in humans,8–10 non-human primates11–13 and dogs.14, 15
