Date of Award:

5-2012

Document Type:

Dissertation

Degree Name:

Doctor of Philosophy (PhD)

Department:

Psychology

Committee Chair(s)

Gregory J. Madden

Committee

Gregory J. Madden

Committee

Timothy A. Shahan

Committee

Amy L. Odum

Committee

Andrew L. Samaha

Committee

Timothy A. Gilbertson

Abstract

Impulsivity represents a substantial and devastating cost to our economic, cultural, and physical prosperity. Using quantitative models of choice behavior, researchers are able to identify environmental conditions likely to promote impulsive decision-making. Such an approach is especially valuable in experimental efforts to better understand how drugs negatively affect choice in humans and nonhumans alike. For instance, pramipexole, a dopamine agonist medication prescribed for Parkinson’s disease, has been associated with reports of increased rates of impulsive behavior. By which behavioral mechanisms pramipexole achieves these effects is unknown and requires further investigation.

The research reported herein sought to clarify pramipexole’s effects on impulsive decision-making in rats according to two objectives. First, the goal of the experiment presented in Chapter 2 was to systematically replicate a previous study that reported an effect of pramipexole that was inconsistent with the extant literature. Second, the goal of the three experiments presented in Chapter 3 was to isolate behavioral processes that could contribute to impulsive choice and to describe quantitatively the mechanism(s) by which pramipexole negatively affects decision-making.

Results suggested that pramipexole significantly disrupted rats’ discrimination of the source of food reinforcement, as well as discrimination of the amount of food received. These impairments are theoretically capable of increasing the probability of impulsive choice and may underlie pramipexole’s effects as reported in the nonhuman drug literature. With respect to clinical instances of impulsive behavior, the present findings have limited generality. The approach documented herein, however, demonstrates the utility of quantitatively modeling aspects of impulsive decision-making in order to better understand complex drug effects.

Checksum

c7472a2bead7393d810152ab91af754d

Comments

This work made publicly available electronically on June 4, 2012.

Copyright 2010 by the American Psychological Association. Reproduced [or Adapted] with permission. The official citation that should be used in referencing this material is:

Madden, G. J., Johnson, P.S., Brewer, A. T., Pinkston, J. W., & Fowler, S. C. (2010). Effects of pramipexole on impulsive choice in male wistar rats. Experimental and Clinical Psychopharmacology, 18(3), 267-276. doi:10.103/a0019244

No further reproduction or distribution is permitted without written permission from the American Psychological Association.

Download

Share

COinS

Copyright for this work is retained by the student. If you have any questions regarding the inclusion of this work in the Digital Commons, please email us at .