Parkinson's Disease Behavior Research Articles

Prevalence of repetitive and reward-seeking behaviors in Parkinson disease

We surveyed 297 patients with Parkinson disease (PD) with systematic screens and rigorous definitional criteria. Pathologic hypersexuality lifetime prevalence was 2.4%. Compulsive shopping was 0.7%. Combined with our pathologic gambling data, the lifetime prevalence of these behaviors was 6.1% and increases to 13.7% in patients on dopamine agonists.

Effects of Donepezil on Compulsive Hypersexual Behavior in Parkinson Disease

Hypersexuality is a known, though not frequently publicized, behavioral disturbance in patients with Parkinson disease. Hypersexuality has been associated with dopaminergic drug therapy. We describe a patient with Parkinson disease who presented with compulsive hypersexual behavior. Lowering of dopaminergic drug doses was of minimal behavioral benefit but was not well tolerated because of worsening of motor function. A trial with donepezil led to significant amelioration of the compulsive behavior without adverse motor effects.

Dopamine Modulates the Response of the Human Amygdala: A Study in Parkinson's Disease

In addition to classic motor signs and symptoms, Parkinson's disease (PD) is characterized by neuropsychological and emotional deficits, including a blunted emotional response. In the present study, we explored both the neural basis of abnormal emotional behavior in PD and the physiological effects of dopaminergic therapy on the response of the amygdala, a central structure in emotion processing. PD patients and matched normal controls (NCs) were studied with blood oxygenation level-dependent functional magnetic resonance imaging during a paradigm that involved perceptual processing of fearful stimuli. PD patients were studied twice, once during a relatively hypodopaminergic state (i.e., > or =12 hr after their last dose of dopamimetic treatment) and again during a dopamine-replete state. The imaging data revealed a robust bilateral amygdala response in NCs that was absent in PD patients during the hypodopaminergic state. Dopamine repletion partially restored this response in PD patients. Our results demonstrate an abnormal amygdala response in PD that may underlie the emotional deficits accompanying the disease. Furthermore, consistent with findings in experimental animal paradigms, our results provide in vivo evidence of the role of dopamine in modulating the response of the amygdala to sensory information in human subjects.

Use of advance information for complex movements in Parkinson’s disease

Motor preparation processes in Parkinson's disease (PD) patients and elderly control subjects were examined by utilizing the movement parameter precue technique in prehension movements to different sized objects. PD patients as well as controls were able to use advance information about object size to reduce their response times. However, further analysis of the response kinematics revealed that in contrast to controls, PD patients showed a prolongation of the transport phase related to the validity of the object size precue when grasping small objects. Therefore, PD patients seem to suffer from a slowing of their qualitatively preserved motor preparation process which becomes more pronounced in complex tasks like prehension. This finding of a qualitatively preserved, but slowed capability in PD patients of using advance information for motor preparation is discussed in the framework of the motor control literature on predictive behavior in PD.