Marín‐Lahoz J, Martínez‐Horta S, Sampedro F, et al. - This study was undertaken to determine if different impulsivity measures in Parkinson disease share substantial inter‐scale and anatomical correlations or rather mirror different underlying phenomena. Four common tests were assessed evaluating different aspects of impulsivity in a consecutive sample of 89 Parkinson disease patients without impulse control disorders: impulsiveness trait, decisions under implicit risk with and without losses, and delay discounting. There were no major differences between the different impulsivity tests. In addition, their structural brain correlates were divergent. In Parkinson disease, different impulsivity measures represent very dissimilar behavioural and brain structural correlates. Findings indicate that parkinsonian impulsivity is a heterogeneous entity, rather than a unitary phenomenon.