English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Probability Discounting of Lewis and Fischer 344 rats: Strain Comparisons at Baseline and Following Acute Administration of d-Amphetamine Jenny E. Ozga-Hess Risky choice can be defined as choice for a larger, uncertain reinforcer over a smaller, certain reinforcer when choosing the smaller alternative maximizes reinforcement. Risky choice is studied using various procedures in the animal laboratory; one such procedure is called probability discounting. There are many variables that contribute to risky decision-making, including biological and pharmacological determinants. The present study assessed both of these variables by evaluating dose-response effects of d-amphetamine on risky choice of Lewis (LEW) and Fischer 344 (F344) rats. The probability-discounting procedure included discrete-trials choices between one food pellet delivered 100% of the time and three food pellets delivered following one of varying probabilities. The probability of three food pellets being delivered decreased systematically across blocks within each session. At baseline, risky choice did not differ between LEW and F344. However, choice for LEW became significantly less risky throughout extended training while choice for F344 remained relatively stable over time. dAmphetamine significantly increased risky choice for both rat strains at low-to-moderate doses (0.1 and 0.3 mg/kg), although it did so at a lower dose for F344 (0.1 and 0.3 mg/kg) than LEW (0.3 mg/kg only), suggesting greater behavioral sensitivity to effects of d-amphetamine for F344. High doses of d-amphetamine (1.0 and 1.8 mg/kg) produced overall disruptions in choice for both strains, indicated by reductions in choice for the larger, uncertain alternative when the probability of delivery was relatively high and increases when the probability was relatively low. Results from the current study stand in contrast to previous reports investigating impulsive choice (i.e., choice involving temporal delays rather than uncertainty) of LEW and F344. Thus, the present work underscores the importance of considering risky and impulsive choice as two separate, but related, behavioral processes. PROBABILITY DISCOUNTING OF LEWIS AND FISCHER 344 RATS iii ACKNOWLEDGEMENTS I would like to thank Dr. Karen G. Anderson, Dr. Melissa D. Blank, Dr. Cole Vonder Haar, Dr. David P. Siderovski, and Dr. Regina A. Carroll for serving on my dissertation committee and for offering valuable feedback throughout this project. I would like to specifically thank my advisor and mentor, Dr. Karen G. Anderson, for her everlasting support, encouragement, and guidance throughout this project and my graduate career. In addition, I thank Drs. Melissa D. Blank and Cole Vonder Haar for sharing their knowledge of statistics with me. Thank you to my lab-mates, Matt Eckard and Devin Galdieri, as well as Nicholas J. Felicione for always asking the tough questions and making me think critically. Thank you to undergraduate research assistants, Darien Beall and Ashley Richmond, for assisting with data collection. In terms of funding, I’d like to thank the Society for the Advancement of Behavior Analysis as well as the Behavioral and Biomedical Sciences research program for providing funding and other resources (e.g., graphical software) to assist with completion of this project. A very special thank you to my parents, John and Mary Ozga, and siblings, Joseph Ozga and Lindsay Mahan, who have always loved, encouraged, and supported me in every aspect of life. Finally, a very special thank you to my husband, Nicholas Hess, for providing a source of stress relief, making me laugh, and providing endless inspiration throughout the course of this project and my graduate career. PROBABILITY DISCOUNTING OF LEWIS AND FISCHER 344 RATS iv TABLE OF CONTENTS Page LIST OF TABLESv LIST OF FIGURESvi-vi