Effects of Alternating Partial Reinforcement and Alternating Delay of Reinforcement on a Runway Response

A replication and extension of the Cogan and Capaldi study was performed, using 60 rats. As in the original study, Ss with alternating reinforcement and nonreinforcement displayed patterned running during runway acquisition; Ss with alternating immediate and delayed reward did not. Additional groups with longer confinement periods exhibited patterned running under both alternating partial and alternating delay of reinforcement. The extinction results were in the opposite direction to those of Cogan and Capaldi; in all comparisons the partially delayed groups ran faster than the corresponding delayed groups.