The role of impulsivity as predisposing behavioural trait in different aspects of alcohol self-administration in rats

Background: Therapeutic interventions to promote abstinence and prevent relapse in alcohol use disorder (AUD) are limitedly available. Therefore, targeting risk factors in the onset and maintenance of AUD could pose an interesting alternative treatment strategy. In this regard, over the last decade trait impulsivity has received considerable attention as such a risk factor predisposing substance dependence both in clinical populations and preclinical rodent studies. This study investigated whether different forms of impulsivity (action versus choice) predict distinct stages of instrumental alcohol self-administration, extinction and cue-induced relapse. Methods: Two cohorts of n = 48 rats each were trained in an operant tasks for either impulsive action or impulsive choice. Subsequently, high and low impulsive rats were then tested in an alcohol self-administration and relapse model and following this retested in the impulsivity tasks to evaluate possible changes in impulsivity levels. Results: The current data show that neither impulsive action, nor impulsive choice predict the extent to which rats consume alcohol and the extent to which rats are motivated to self-administer alcohol. Moreover, extinction of responding for alcohol and cue-induced relapse was not predicted by impulsivity. Interestingly, rats and most prominently low impulsive rats became more impulsive after the alcohol self-administration procedure. Although due to employed experimental design it is not clear whether this resulted from alcohol consumption or alcohol abstinence. Conclusion: Together, these findings lend further support for the notion of a unidirectional relationship between self-administration of the depressant drug alcohol and impulsivity.