[Impairment of social cognition in Parkinson's disease]

The characteristic four symptoms of motor deficits, bradykinesia, rigidity, resting tremor and impairment of postural reflex with Parkinson's disease (PD) are accompanied by specific cognitive deficits. Deficits of executive functions, skill learning, and visuospatial cognition are well known. The results of our recent studies show the deficit of social cognition which include facial expression recognition, sensation of gaze direction, "theory of mind" in comprehension, and decision making. These symptoms can be explained by the damage of the amygdala and/or its connection, which are known to play a crucial role in social cognition, it is attributed to the involvement of amygdala and it's connection to the frontal lobe in PD. The impairment of social cognition is an important mental change associated with PD.