Doctor of Clinical Neuropsychology/Master of Science / Introduction: Parkinson’s disease (PD) is known to cause detrimental effects to motor function and cognition. The motor effects of the disease in turn impact emotion expression in patients with PD. There is conflicting evidence in research, however, as to whether PD also affects emotion comprehension, and if so, what emotions in particular are affected and across what modalities. This study aimed to investigate the effects of PD on a broad range of skills involved in basic and complex emotion comprehension. Whether these effects extend into other areas associated with emotion processing, such as social cognition and autobiographical memory, was also explored. Methods: Sixteen patients with PD participated in the study along with sixteen control subjects who were matched for age, gender, education level and estimated premorbid intelligence. The PD participants, on average, were in the moderate phase of the disease and taking PD medication, including dopamine. Participants were tested on a range of recognition measures including prototypical and morphed facial expressions with reduced intensity (40 and 80%), emotion prosody, written emotion vignettes, emotional imagery, pictures of emotion, social cognition, and a cued autobiographical memory task. A mood inventory was given, and disease severity and duration were noted. Results: The PD group did not show pervasive deficits in emotion recognition overall. Deficits were demonstrated in prosody recognition, specifically with fearful tones, and in an incongruent prosody task, specifically with angry and neutral tones. The PD group was not able to recognise facial expressions of disgust (mixed intensities) as well as controls, with the result showing a trend toward significance. PD participants were also significantly worse in Theory of Mind (TOM) reasoning but not at another social cognition measure involving recognising social emotions through expressions from the eyes only. There were no differences between the groups across all other tests. Discussion: PD is thought to cause subtle deficits in emotion comprehension which are only elucidated through complex tasks. The effects of PD on complex processing also impact TOM performance, which relies on skills involved in complex emotion recognition. Effects of mood and disease factors on performance were circumscribed. Evidence suggested that the basal ganglia and fronto-striatal connections play a role in emotion comprehension.

Doctor of Clinical Neuropsychology/Master of Science / Introduction: Parkinson’s disease (PD) is known to cause detrimental effects to motor function and cognition. The motor effects of the disease in turn impact emotion expression in patients with PD. There is conflicting evidence in research, however, as to whether PD also affects emotion comprehension, and if so, what emotions in particular are affected and across what modalities. This study aimed to investigate the effects of PD on a broad range of skills involved in basic and complex emotion comprehension. Whether these effects extend into other areas associated with emotion processing, such as social cognition and autobiographical memory, was also explored. Methods: Sixteen patients with PD participated in the study along with sixteen control subjects who were matched for age, gender, education level and estimated premorbid intelligence. The PD participants, on average, were in the moderate phase of the disease and taking PD medication, including dopamine. Participants were tested on a range of recognition measures including prototypical and morphed facial expressions with reduced intensity (40 and 80%), emotion prosody, written emotion vignettes, emotional imagery, pictures of emotion, social cognition, and a cued autobiographical memory task. A mood inventory was given, and disease severity and duration were noted. Results: The PD group did not show pervasive deficits in emotion recognition overall. Deficits were demonstrated in prosody recognition, specifically with fearful tones, and in an incongruent prosody task, specifically with angry and neutral tones. The PD group was not able to recognise facial expressions of disgust (mixed intensities) as well as controls, with the result showing a trend toward significance. PD participants were also significantly worse in Theory of Mind (TOM) reasoning but not at another social cognition measure involving recognising social emotions through expressions from the eyes only. There were no differences between the groups across all other tests. Discussion: PD is thought to cause subtle deficits in emotion comprehension which are only elucidated through complex tasks. The effects of PD on complex processing also impact TOM performance, which relies on skills involved in complex emotion recognition. Effects of mood and disease factors on performance were circumscribed. Evidence suggested that the basal ganglia and fronto-striatal connections play a role in emotion comprehension.