College of Arts & Sciences

Date of Award


Document Type

Research Project Report

Degree Name

Master of Arts (MA)



First Advisor

J. Greenspan, Ph.D.

Second Advisor

James Olson, Ph.D.

Third Advisor

Robert Rothstein, Ph.D.


The effect on response rates during extinction of interpolating seven continuous reinforcement sessions after varying numbers of VR-25 sessions was investigated. Rats received either seven, fourteen, or twenty-one sessions of a VR-25 schedule followed by seven sessions of continuous reinforcement. There were three rats in each group. The rats then experienced seven sessions of extinction. All sessions were 30 minutes long." The results showed that rats that received the VR-25 schedule for 21 sessions made the roost responses over the seven extinction sessions. * Rats that received seven sessions of VR-25 made the least number of responses during extinction. The results were not statistically significant. However, they did indicate that interpolated continuous reinforcement did not decrease response rates during extinction for rats that experienced a large number of prior VR-25 schedules.