Objectives: Although impulsiveness (or impulsivity) is considered to be an important symptom of many psychiatric disorders, it lacks a univocal and commonly accepted definition. The article presents different theories and models of impulsivity.
Background Attempts at producing a consistent and universal definition of impulsivity, as well as difficulties resulting from complexity of the phenomenon are described. The concepts ofbehavioural and cognitive, functional and dysfunctional impulsivity are outlined. Mor eover, psychiatric disorders associated with high levels of impulsivity and the idea of transient, state-related impulsiveness are discussed. The issue of impulsivity as a stablepersonality trait is analyzed in terms of variouspsychological models, and methods to measure impulsiveness are brieflypresented.
Conclusions. The failure to produce a univocal definition of impulsiveness along with the fact that elements of this phenomenon are present in so many areas ofpsychopathology may be explained by heterogeneity and complexity of the construct.