Parkinson's Disease (PD) is a common and debilitating neurodegenerative disease. While medication can alleviate its symptoms, not all patients will adequately respond to medical therapy. For these cases, deep brain stimulation (DBS) has been used to improve symptoms and quality of life. Nevertheless, this approach is, in some cases, associated with incapacitating neuropsychiatric side-effects, including mood disturbances, such as DBS-induced mania. While this condition has important functional short- and long-term consequences for quality of life and prognosis, its pathophysiology is still poorly understood. In this project the investigators propose to conduct a retrospective and naturalistic study in PD patients in whom DBS stimulation resulted in mania or mixed state episode, to clarify if specific sociodemographic and clinical predictors, namely stimulation parameters and target locations, might be associated to the occurrence of this neuropsychiatric adverse event. Additionally, the investigators aim to clarify if the occurrence of DBS-induced mania results from the impact of specific stimulation parameters and/or target locations in functional connectivity networks. To explore this question, the investigators will use different neuroimaging analysis methods termed lesion topography analysis and lesion network mapping, in order to compute maps of the stimulated regions topography and the functional networks that are associated with DBS-mania, respectively. The data that will be analyzed in this project, including neuroimages, will be obtained retrospectively, by different Movement Disorders and Functional Surgery Groups in the context of Deep Brain Stimulation, and that has been collected according to their usual clinical practice.