The risky business of dopamine agonists in Parkinson disease and impulse control disorders.

Claassen, D. O., van den Wildenberg, W. P. M., Ridderinkhof, K. R., Jessup, C. K., Harrison, M. B., Wooten, G. F., & Wylie, S. A. (2011). The risky business of dopamine agonists in Parkinson disease and impulse control disorders. Behavioral Neuroscience, 125(4), 492-500. doi:10.1037/a0023795

The second article I chose for chapter 16 was over the neurological disorder Parkinson’s disease. Although there has been a lot of research done over neurological and psychological disorders, studies are constantly evolving what we know about these disorders. Parkinson’s disease is related to the degeneration of the substantia nigra and loss of the neurotransmitter dopamine. Symptoms of Parkinson’s disease include tremor at rest, muscular rigidity, akathesia, disorders of posture, disorders of locomotion, slowness of movement, and disturbances of speech. This disorder could be caused by encephalitis, syphilis, and drugs. The title of the article I chose was “The risky business of dopamine agonists in Parkinson’s disease and impulse control disorders.” The researchers in this study said that in spite of potential negative consequences, risk taking behavior is described by the chase of a reward. The neurotransmission of dopamine in the mesocortilimbic pathway was found as a modulator of risk behavior. This study evaluated patients with Impulse control disorder and Parkinson’s disease. Impulse Control Disorder is characterized by hyper-sexuality, compulsive gambling, eating, and shopping. These compulsive behaviors are associated with risky behavior. These behaviors are also thought to be the result of dopaminergic medication. Researchers used the Balloon Analogue Risk Task to assess the how agonist therapy affected risk behaviors in Parkinson’s patients that were diagnosed with impulse control disorder and actively displayed symptoms. There were a total of 41 participants: 22 with ICD and 19 without ICD. Researchers asked the patients to perform the task both “on” and “off” dopamine agonists. Dopamine agonists increased risk-taking in Parkinson’s disease patients with active ICD symptoms, but it did not have an effect on the control. The dosage was also an important factor in explaining risk behavior. Reduced risk taking was reported for both groups in high versus the low risk condition with negative consequences involved. Researchers also found that patients with Impulse Control Disorder were not impaired in processing and adjusting to negative consequences.