Date of Graduation


Document Type


Degree Type



Eberly College of Arts and Sciences



Committee Chair

Kennon A. Lattal

Committee Member

Kathryn Kestner

Committee Member

Michael Perone

Committee Member

Barry Edelstein

Committee Member

Nyles Charon


Experimental analyses of coordinated responding (i.e., cooperation) have been derived from a procedure described by Skinner (1962) in which reinforcers were delivered to a pair of subjects (a dyad) if both responded within a short interval, thus satisfying a mutual-reinforcement contingency. Although it has been suggested that this contingency enhances rates of temporally coordinated responding, limitations of past experiments have raised questions concerning this conclusion. The present experiments assessed three of those limitations by holding the schedule of reinforcement (Experiment 1: fixed-ratio 1; Experiment 2; variable-interval 20 s) constant (1) across phases and (2) between dyad members, and (3) varying the number of keys across which responses could be coordinated. Greater percentages of coordinated responding were observed under mutual- than under independent-reinforcement phases in most conditions. The one exception during the one-key condition of Experiment 1 appeared to be a consequence of variability during the independent-reinforcement phase. Furthermore, coordination percentages decreased systematically with increasing response options. The present results thus confirm that mutual-reinforcement contingencies induce higher rates of temporally coordinated responding than independent-reinforcement contingencies. The results further indicate that the effects of mutual-reinforcement contingences can be influenced by the environmental context in which those contingencies operate.