Pathological gambling and obsessive-compulsive disorder: towards a spectrum of disorders of volition Jogo patológico e transtorno obsessivo-compulsivo: rumo a um espectro de transtornos da volição A b s t r a c t Objective: Pathological gambling is proposed as a participant of an impulsive-compulsive spectrum related to obsessive-compulsive disorder. This study aims to contrast pathological gambling and obsessive-compulsive disorder regarding course, comorbidity, and personality, hence testing the validity of the impulsive-compulsive spectrum. Method: 40 pathological gambling and 40 obsessivecompulsive disorder subjects matched to 40 healthy volunteers according to gender, age, and education were assessed with the Temperament Personality Questionnaire and the Barratt Impulsiveness Scale. Psychiatric patients were also assessed for course and comorbidity data. Results: Obsessive-compulsive disorder presented an earlier onset, but the full syndrome took longer to evolve. Pathological gambling had higher comorbidity with substance-related disorders, and obsessive-compulsive disorder higher comorbidity with somatoform disorders. Gamblers scored higher than controls on the sub-factors Impulsiveness, Extravagance, Disorderliness, and Fear of Uncertainty. Obsessive-compulsive patients scored higher than controls on Fear of Uncertai-nty. Impulsiveness, Extravagance, and Disorderliness significantly correlated with the Barratt Impulsiveness Scale total score, Fear of Uncertainty did not. Discussion: The course and comorbidity profiles of pathological gambling resemble an addiction and differ from obsessive-compulsive disorder. Pathological gambling combines impulsive and compulsive traits. Impulsivity and compulsivity should be regarded as orthogonal constructs, and as drives implicated in volition aspects of behavioral syndromes.