Taken together, these findings suggest that facilitative conditions for the emergence of individual differences in urgency can be identified at the neurogenetic, neurotransmitter, and brain system levels. It is possible that gene polymorphisms contribute to low 5HT and high DA in the OFC – amygdala pathway, which undermine affect-guided planning and lead to actions not in one's long-term interests. Thus, characteristically low 5HT and high DA levels in this brain region may contribute to formation of the urgency traits. To date, though, no studies have tested relations among the gene polymorphisms, the neurotransmitter activity in this brain system, and measures of the urgency traits. Doing so constitutes an important next step in validation this proposition.
