Novelty Seeking and Drug Addiction in Humans and Animals: From Behavior to Molecules

Global treatment of drug addiction costs society billions of dollars annually, but current psychopharmacological therapies have not been successful at desired rates. The increasing number of individuals suffering from substance abuse has turned attention to what makes some people more vulnerable to drug addiction than others. One personality trait that stands out as a contributing factor is novelty seeking. Novelty seeking, affected by both genetic and environmental factors, is defined as the tendency to desire novel stimuli and environments. It can be measured in humans through questionnaires and in rodents using behavioral tasks. On the behavioral level, both human and rodent studies demonstrate that high novelty seeking can predict the initiation of drug use and a transition to compulsive drug use and create a propensity to relapse. These predictions are valid for several drugs of abuse, such as alcohol, nicotine, cocaine, amphetamine, and opiates. On the molecular level, both novelty seeking and addiction are modulated by the central reward system in the brain. Dopamine is the primary neurotransmitter involved in the overlapping neural substrates of both parameters. In sum, the novelty-seeking trait can be valuable for predicting individual vulnerability to drug addiction and for generating successful treatment for patients with substance abuse disorders.