Some Parkinson’s Patients Grow More Impulsive

A small proportion of Parkinson’s disease patients may develop a tendency to engage in impulsive behaviors such as gambling. Experts attribute these behaviors to the decrease in dopamine that occurs in PD patients' brains. As dopamine decreases, the mind compels some PD patients to seek pleasure as a substitute. Medical professionals have particularly found this behavior in patients that are taking dopamine antagonists. One physician explains:

Such an odd shift in behavior, while not fully understood, seems to be based on the amount of dopamine circulating in the brain. This chemical is believed to act as a natural reward mechanism, helping to control how we define pleasure. When dopamine is at a normal level, there is less of a need to seek outside stimulation. But when the chemical is out of kilter, researchers have found the people are prone to all kinds of vices, from obsessive eating to becoming addicted to drugs.

Click here to read a great synthesis of the research that exists on this issue. The article also cites this Mayo Clinic study, tying PD to an increase in gambling participation. The story also references a study by Columbia University that indicates that dopamine antagonists may also encourage PD patients to eat more, and consequently gain weight. This was a small study of just seven patients. The findings were compelling, but the researchers decided that “. . . further investigation is warranted.” If you have noticed new compulsive behaviors in yourself, or if you as a friend or caretaker notice them in a PD patient, please point them out to your neurologist.