Date of Award


Degree Name

Master of Arts



First Advisor

Dr. Jack L. Michael

Second Advisor

Dr. Alan Poling

Third Advisor

Dr. Lisa Baker

Access Setting

Masters Thesis-Open Access


Relative to their reinforcing and discriminative functions, the establishing operation (EO) function of drugs has received little attention from behavioral pharmacologists. This study investigated in rats the EO function of 3,4-methylenedioxymethamphetamine (MDMA, Ecstasy) using a progressive-ratio (PR) 2 schedule of water delivery. Relative to vehicle control levels, Lower doses (1.0 and 1.8 mg/kp ip) had no effects, whereas the higher doses (3.2, 5.6 mg/kg ip) significantly decreased breaking points. In contrast to previous research, this study found no evidence that MDMA functioned as an EO for water. These results, along with findings from other studies using PR schedules, emphasize the need for caution when interpreting drug-induced changes in breaking points.

Included in

Psychology Commons