Dissertation Defenses

Doctoral Dissertation Announcement

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Candidate: Marc Weeden

Degree of: Doctor of Philosophy

Department: Psychology

Title: The Effects of Chlordiazepoxide on Resurgence in Male Rats: A Preliminary Investigation

Committee:
Dr. Alan Poling, Chair
Dr. Stephanie Peterson
Dr. Ron Van Houten
Dr. Frans van Haaren

Date: Thursday, July 8, 2010 1:00 p.m. - 3:00 p.m.
3715 Wood Hall

Abstract:
Resurgence is defined as the recurrence of a previously but no longer reinforced behavior when a more recently reinforced behavior undergoes extinction. The present study investigates the effects of chlordiazepoxide (CDP), a member of the class of drugs known as benzodiazepines, on the resurgence of lever pressing responses emitted by male Sprague-Dawley rats. The general procedure was as follows: An operant (left lever presses) was reinforced and subsequently extinguished. Then, a second operant (right lever presses) was reinforced. Finally, 0, 1, 3, 10, and 30 mg/kg doses of CDP were administered via intraperitoneal injections to groups of nine animals each during three consecutive days of 1-hr exposure to concurrent extinction schedules. Slightly more left lever pressing (the resurgence response) occurred in the 1 mg/kg group than in the control group while dose-dependent decreases in resurgence, as well as overall responding, occurred in the 3, 10, and 30 mg/kg groups relative to control levels. These results are discussed in terms of their similarity to those found in investigations of the effects of benzodiazepines on extinction.