Date of Graduation


Document Type


Degree Type



Eberly College of Arts and Sciences



Committee Chair

Kennon A. Lattal.


The discriminative properties of schedules of reinforcement have been assessed by making a choice response conditional upon some aspect of the schedule that produced the choice component. The discriminative properties of concurrent schedules of reinforcement and the effect of disruptions in the response-reinforcer relation were investigated using conditional-discrimination procedures. In the first experiment, choice components were produced by responding to one of two variable-interval (VI) schedules. Disruptions in the temporal contiguity between a VI response and a choice component were introduced by arranging a percentage of choice components according to a variable-time schedule. Choice responding was a function of the response that produced the choice component. Delays of up to 0.5 s resulted in responding that corresponded to the last VI response made.;In the second experiment, the delay between a VI response and choice component was controlled for by arranging choices according to concurrent VI and differential-reinforcement-of-other-behavior (DRO) schedules. Choice responding was a function of which schedule arranged the choice component. Varying the DRO value resulted in increased choice accuracy at shorter (0.25 to 2.00 s) delays and decreased accuracy at delays of greater than 2.00 s. These results indicate that concurrent schedules of reinforcement can serve a discriminative function and that the discriminative properties of response-reinforcer relations are a function of the temporal contiguity between a response and a stimulus change.