The effects of cocaine and morphine on avoidance responding at different levels of food deprivation.
Date of Graduation
1998
Document Type
Thesis
Degree Type
MA
College
Eberly College of Arts and Sciences
Department
Psychology
Committee Chair
David Schaal
Committee Member
Anne Watson
Committee Member
David Schaal
Abstract
Three rats deprived to 80% of free-feeding weight pressed a bar to avoid electric shock in a Sidman avoidance procedure (20 s R-S interval, 5 s S-S interval). Once responding became stable, two of the rats were reduced to 70% of free feeding weight and one rat’s weight was increased to 95%. Cocaine (10.0, 17.0, 30.0, 40.0 mg/kg), morphine (5.6, 10.0, 17.0, 30.0, 40.0) and saline were tested in a random series with multiple determinations. Rate of responding and avoidance proficiency were recorded. When the injection series was completed the rats were free-fed and their weights redetermined so that the two rats that were at 70% of free-feeding weight were increased to 95% and the rat at 95% was reduced to 70%. Then the rats were tested again. Morphine produced little systematic change in rate or proficiency. Cocaine produced a dose-dependent increase in responding, but little change in proficiency. Economic versus stress hypotheses are discussed.
Recommended Citation
Layng, Michael Phillip, "The effects of cocaine and morphine on avoidance responding at different levels of food deprivation." (1998). Graduate Theses, Dissertations, and Problem Reports. 10377.
https://researchrepository.wvu.edu/etd/10377