Impulsivity as a Predisposing Vulnerability Trait for Reward Sensitivity and Volitional Drug Self-administration: A Scoping Review

Abstract Purpose of Review Trait impulsivity is considered as a risk factor for substance use disorders. Over the last decades many preclinical translational studies in rodents have been carried out to understand the relationship between trait impulsivity and reward sensitivity, including volitional drug self-administration. This scoping review provides an update on the collective translational work examining the relationship between impulsivity and sensitivity to drug and natural rewards. Recent Findings Using a systematic search strategy, we included 59 articles retrieved from the databases PsychInfo and Pubmed. Results from the selected articles revealed that impulsivity is a significant risk factor for volitional drug consumption in rodents, with highly impulsive rodents showing greater sensitivity towards stimulant drugs, such as amphetamine, cocaine and nicotine. Such a relationship was less straightforward for the depressant drug alcohol and for natural reinforcers, including food reinforcement. The studies on opioid drugs revealed that trait impulsivity does not predict volitional self-administration or sensitivity towards these drugs. Summary Taken together, the current evidence from translational studies strongly suggests that impulsivity is a risk factor for stimulant use. As such, the collective findings suggest that targeting impulsivity may have potential as a prevention strategy in the onset of substance use disorders and/or as an intervention to promote abstinence in drug-dependent subjects. At the same time, the current results clearly show that this cannot be generalized to all drug classes and thus urge for drug-specific approaches.