The Effects of Lag Value on the Operant Control of Response Variability Under Free-Operant and Discrete-Response Procedures

Abstract

The effects of different reinforcement requirements on the operant control of response variability under free-operant and discrete-response procedures were investigated. Six pigeons were required to emit a sequence of four responses on two keys that differed from the previous 2, 4, or 6 sequences (lag value) to obtain reinforcement. Pigeons were exposed to each lag value under a free-operant procedure in which the key lights remained illuminated throughout each trial, and a discrete-response procedure in which a brief time-out (key lights off) followed each response. Consistent with previous findings, the discrete-response procedure produced substantially greater variability than the free-operant procedure. Additionally, as lag value increased, response variability also increased. It was concluded that both type of procedure (free-operant vs. discrete-response) and lag value contribute to the operant control of response variability.