We describe a patient with Parkinson's Disease who underwent bilateral subthalamic nucleus deep brain stimulation and later presented with episodes of aggressive behavior disorder with disturbed impulse control and an inability to control anger likely related to the deep brain stimulation "switch-on stimulation". We hypothesize that increasing voltage intensity could influence neighboring passing fibers coming from basal limbic system that are involved in the regulation of affect and emotional behavior. We suggest investigating these neuropsychological disturbances considering their influence on quality of life after surgery.