Response rate in the appetitive link of homogeneous and heterogeneous chains in rats

Abstract

In two-component chain schedules, rates of responding during the first component are higher when similar responses are required in both components. Previous research, however, has used only pigeons and has confounded response similarity with response location. The present study attempted to replicate the finding with rats shile separating response similarity and location. Three rats completed chains where barpressing or leverpulling was required in either component. In addition, the two different responses were balanced across conditions such that they were the same or different and had to occur in the same or a different location. In four out of six conditions where the responses were similar and occurred in the same location, first-link rates were higher than in any other comparable condition. These findings show that homogeneous chain effects are general across rats and pigeons and that distance between operanda does contribute to the effect.