The Impact of Pretraining on Autoshaping and Operant Acquisition in Rats is Significant but Transient

Abstract

Pretraining refers to events or conditions explicitly arranged prior to the learner (e.g., student, employee) experiencing specific instruction within the learning environment (i.e., training). Such pretraining can occur inside or outside of the specific learning environment, but by definition must precede the onset of training. Pretraining can modify the rate and quality of early learning and the final performance levels attained. Within experimental psychology, laboratories often include pretraining to hasten acquisition, but few empirical studies support this practice. Therefore, in the present study, four distinct levels of pretraining were examined by randomly assigning 284 naïve rats into groups: no training, chamber acclimation, pellets only, or magazine training. By manipulating experience with the chamber, food pellets, and stimuli associated with pellet delivery, direct assessments were made of pretraining on autoshaped lever press acquisition and incremental progress through a fixed order of common (ratio and interval) schedules of reinforcement. Pretraining affected acquisition, and the several measures of learning corroborated the presumed benefits of magazine training. Notably, simple pre-exposure to the chamber (both with pellets and without pellets in the magazine) also promoted acquisition compared to the no-training group. Nevertheless, despite clear benefits upon acquisition in early sessions, comparable levels of performance developed as training progressed, with the exception of higher lever-pressing rates from the magazine-training group compared to the pellets-only and chamber-acclimation groups. Magazine training hastened operant acquisition, but the overall benefit was somewhat diminutive and short-lived, and the practical value of these pretraining procedures on subsequent operant performance appears limited.

Keywords: autoshaping; lever pressing; magazine training; pretraining; rat.