Impulsivity can be a problem in Parkinson’s Disease due to the deficiency in dopamine. We have two major parts of the study regarding impulsivity.
Delayed Discounting Task
The delayed discounting task measures an individual’s perception of value over time. The experiment is a series of choices between a smaller amount of money available today and a larger amount of money at a later point in time. For example: “would you rather have $25 today or $50 in 100 days?” We have adapted this traditional neuroeconomic experiment with a novel priming stimulus to measure the impact of religious concepts on participants’ choices. Our hypotheses are:
- Compared to individuals with Parkinson’s Disease, controls will choose the larger-later amount of money more often.
- When Parkinson’s patients are OFF their medication they will be more likely to choose the smaller-sooner amount of money then when they are on their medication.
- Compared to neutral primes, the religious primes will shift discounting rates toward choosing the larger-later amount more often.
Questionnaire for Impulsive-Compulsive Disorders in Parkinson’s Disease (QUIP)
The QUIP assesses the major impulsivity problems PD patients may have. This is a self-administered survey given to the patient as well as a caretaker, when they are accessible. The main types of impulsivity looked at are as follows:
- Spending too much time on certain behaviors (hobbies, motor activities, walking/driving without purpose, etc.)
We are also looking at medication, as that is usually what drives these impulsivity problems to occur. Those on the dopamine agonist are more likely to exhibit these behaviors because it targets the D2 receptor, which is thought to be the most responsible for inhibiting impulse control. Levodopa, on the other hand, floods all of the dopamine receptors. We expect to find that those who show the most impulsivity levels will be on the agonist.