Patients with Parkinson's disease (PD) exhibit impairments in the execution of highly practiced and skilled motor actions such as handwriting. The analysis of kinematic aspects of handwriting movements has demonstrated that size, speed, acceleration and stroke duration are affected in PD. Although beneficial effects of dopaminergic therapy in regard to execution of movements have been reported, the effects of pharmacological therapy on these measures have not been examined in detail. The present study has compared kinematic aspects of handwriting movements of 27 healthy subjects and 27 patients with PD both on their usual dopaminergic treatment and following withdrawal of dopaminergic medication. Healthy subjects were matched with PD patients according to age, sex, handedness and education level. A digitising tablet was used for the assessment of handwriting movements. Subjects were asked to perform a simple writing task. Movement time, distance, velocity, acceleration and measures of fluency of handwriting movements were measured. Compared with healthy subjects, the kinematics of handwriting movements in PD patients were markedly disturbed following withdrawal of dopaminergic medication. Although dopaminergic treatment in PD patients resulted in marked improvements in the kinematics of handwriting movements, PD patients did not reach an undisturbed level of performance. The results suggest that dopamine medication results in partial restoration of automatic movement execution.

Groups of patients with Parkinson's disease (PD), striatonigral degeneration-type multiple system atrophy (MSA) or progressive supranuclear palsy (PSP) with motor disability stages II and III according to Hoehn and Yahr, and a healthy control group were compared using neuropsychological tests of executive functions. The results indicate that all three patient groups were impaired in the tests of executive functions. In comparison with healthy subjects, the three patient groups showed impaired performance regarding verbal fluency, problem solving and verbal and figural working memory. Patients with PD differed significantly from healthy subjects in a test of verbal recency, while patients with MSA or PSP were unimpaired. The comparison of patient groups revealed no differences between PD and MSA patients. However, patients with PSP showed greater impairment in both phonemic and semantic fluency than patients with PD or MSA. Using discriminant function analysis, it was found that variables derived from four verbal fluency tasks (simple and alternate semantic and phonemic fluency) discriminated among the three patient groups at a level significantly exceeding chance. Over 90% of patients with PSP were correctly classified. Patients with PD and MSA were correctly classified in over 70% of cases. These results suggest that verbal fluency tasks may be sensitive measures in the differential diagnosis of PD, MSA and PSP.

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Psychopathy, a developmental disorder characterized by profound social disturbance, is associated with impaired recognition of distress cues. Since distress processing and moral socialization are closely linked, uncovering techniques to improve distress recognition could have positive treatment implications for developmental disorders that feature empathy impairments. Previous studies demonstrate that fear-recognition deficits can be remedied by redirecting attention to critical cues (the eyes for fearful faces). However, it remains unclear whether this manipulation increases activity in empathy-related brain regions, or has an alternate compensatory effect that may not promote prosocial behaviours. In this fMRI study, a community sample of individuals with high vs low callous traits completed an emotion recognition task that varied whether the most or least socially meaningful facial features were visible (the eyes were isolated or occluded). For fearful faces, individuals with high callous traits showed significantly less amygdala and medial prefrontal cortex activity than those with low callous traits when the eyes were occluded, but not when they were isolated. Consistent with recent models of the amygdala that emphasize orientation to disambiguate stimuli rather than represent distress, individuals with low trait empathy showed greater amygdala activity to the least vs most socially meaningful features of fearful faces.