Motivational Deficits in Parkinson’s Disease: Role of the Dopaminergic System and Deep-Brain Stimulation of the Subthalamic Nucleus

Abstract

Recent experimental and clinical evidence clearly highlights a critical role of dopamine in apathy in Parkinson's disease (PD). Whether apathy intrinsically results from the loss of dopamine in the nigrostriatal system or the progression of dopamine loss toward more limbic areas, or from other variables associated with of deep brain stimulation of the subthalamic nucleus, remains a matter of debate. However, in light of the recent data presented in this chapter, it may be proposed that different etiological factors all contribute to the development and occurrence of apathy, or of different forms of apathy, in PD. Although the present chapter focuses on the role of dopamine, it must be emphasized that the noradrenergic and serotoninergic systems are also likely to be involved in the pathophysiology of PD-related neuropsychiatric symptoms. Some forms of apathy, non-responsive to dopaminergic medication, have also been found to be associated with executive dysfunction or with atrophy of specific basal ganglia or cortical structures. Therefore, apathy, and related affective impairments, in PD can be considered a complex and multifactorial entity. (PsycInfo Database Record (c) 2022 APA, all rights reserved)