DRL responding under conditions of total darkness

Abstract

The effects of total darkness on DRL schedule control were studied with pigeons under two lighting conditions. Increased DRL schedule control is indicated by decreased response and response/reinforcer rates and by increased reinforcer rates. Four pigeons with prior training on DRL schedules were conditioned to keypeck in total darkness. There were five blocks of sessions. In Blocks 1-4, subjects were trained on four alternating blocks of sessions under dark and light conditions (ABAB design). Block 5 consisted of four alternating sessions of dark and light conditions (ABAB design). Comparison of the dark with the light condition showed 3 subjects with decreased response and response/reinforcer rates and increased reinforcer rates in the dark condition. The results indicate increased control with DRL schedules under conditions of total darkness and are in agreement with Robinson and Shelley's (1974) study in which increased control was demonstrated for FI, VI, FR, and VR schedules.