Basic and social emotion recognition in patients with Parkinson disease

The loss of dopaminergic neurons in Parkinson Disease (PD) patients has been associated with impaired emotion recognition. It has been speculated in previous studies that patients with hypodopaminergic state exhibited weaker amygdala activation in response to facial stimuli. In this study we investigate the processing of social and basic emotions through facial expressions in a sample of seventeen idiopathic PD patients matched by age and education level to a group of twenty healthy controls. Our goal was to assess participants' ability to recognize facial expressions of five basic emotions (happiness, fear, sadness, anger and surprise) and three social emotions (arrogance, guilt and jealousy). The basic emotions' group was assessed through a forced-choice labeling task whereas for the social emotions' group a Go/ No-Go task was designed. Our results suggest that PD participants' recognition of basic and social emotions was overall reduced relative to controls, with significant differences for facial expressions of fear and anger (basic emotions' group) and facial expressions of arrogance (social emotions' group). These results were discussed within a framework suggesting that hypodopaminergic state is an influence in basic and social emotion recognition.