Facial emotion recognition in Parkinson's disease: methodological, clinical, and pathophysiological factors

Abstract In the last decade the influence of nonmotor symptoms on the motor performance of Parkinson's disease (PD) patients has been the subject of several studies. In this chapter we focus on the role played by emotional processes that have been studied through research conducted in laboratory or clinical settings. The studies reviewed in this chapter clearly show how PD negatively influences the affective life of patients. More specifically, research on emotional processes and expressions suggests that PD patients may exhibit significant deficits in nonverbal communication, with difficulties in producing emotional facial movements and recognizing the emotions of other people. Several studies demonstrate how patients with PD may display deficits in performing emotion recognition tasks; this seems particularly true for experimental tasks involving prosodic stimuli with a negative valence. Other studies have shown mood alterations and emotional dysfunctions including depression, apathy, and anxiety as well as alexithymia.